Yes, I know this is off subject, but I’ve had a lot of hits around DG Patios, a post I did when I was in California. I thought I’d do a post devoted to that with a few photos.
I’ve done 100′s of decomposed granite patios and walkways in northern California and learned a few things as I went along. When I first began, the industry didn’t have a ‘hardener’ that you could add. That made for a semi-successful installation, because in the winter your walkway was mushy at best. With the advent of hardeners, the DG comes out quite nice, with minimal mush.
Get the DG pre-mixed with the hardener (some landscape outfits will deliver like this) or mix on your own in a wheelbarrow per the proportion instructions. Prepare a bed that’s about 5″ deep. Use an attractive edging. I am totally committed to Ryerson header, which is a thin hard steel that’s bendable. That’s because it disappears. It is expensive though, comes in 16′ lengths with its own stake. The other plastic headers are ugly. An alternative are the many colors and types of Trek, which is a recycled plastic material. Use the 1/2″ wide size. The advantage is that its more bendable than the steel, but it doesn’t disappear, so its part of your project design.
DG path using gold fines with low cost header
Lay down several inches of road base and use a compacter to compact it very hard and tight. Order enough DG to lay down 2″ on top, compacted. Then here’s the secret: apply the DG (with the hardener mixed in good) at the rate of 1/2″ at a time. Then compact. If you apply too thickly, the stuff won’t harden well. The DG has to be moist when putting it down, but not sloppy. Compact 1/2″ at a time till you have your desired height. Sprinkle with water.
Another method I’ve used quite successfully was told to me by the contractor at Strybing Arboretum in San Francisco. All their paths are done this way, and they get tons of traffic. For this method, DON’T use hardener. Apply a good road base foundation of several inches, maybe 3 or 4″. Then apply only 1/2″-3/4″ of compacted DG. Essentially this is a dusting. You will have to reapply every few years depending on your traffic. I used this method for a patio over 4 years ago and still have not reapplied. I think this is a superior method because you completely eliminate any winter mushiness. Even with a hardener there will be some mushiness.
Local fines used as DG
Some warnings: DO NOT try to apply a hardener after the fact. I once went to a potential job where the gardener had installed a walkway, then put the hardener in after he was done. Oh my God! What a mess. The whole thing had to be removed and redone.
Closeup of local fines and 3 Rivers Paver inserted for effect
Next warning. Do not install DG directly next to an indoor situation. DG tracks. It’s granite and granite gets on your shoes and gets in the house. You need at least a few steps (not many) before you go inside. My son’s elementary school built a new gym for millions of dollars. The landscape architect speced DG as the hardscape all around the gym. That was a disaster. All those kids tracked that DG into the new hardwood floor and ruined it! They finally installed concrete as a spacer.
Gray DG with Ryerson edging on one side and wooden PT rounds on the other
Next, the materials. Of course, every area is different. DG in the Bay Area came in gray, gold, or dirt brown. I’ve mixed them for different colors. Don’t be afraid to experiment a bit. A new rock came out on the market from a local quarry that was cheaper (DG is expensive. Last I looked it was around $80/yard!). I was able to get ‘fines’ and used that successfully with the hardener for a coral color.
Ryerson header and granite block decorative edge. Gravel and paver at left
For patios, (see my complete post on patios)I usually don’t like to have a visible drain, so I put the drain(s) on the outside in the shrub area. The exceptions are like the previous post with the photo of the sunken patio. Of course, I had no choice. But really, always remember your drainage.
One neat new alternative to DG is permeable concrete. Its more expensive than ordinary concrete, but it is nicer, much nicer, on the environment. Its fairly new and my understanding is that a good powerwash in the spring opens the pores and keeps it permeable.
Permeable concrete
Permeable concrete closeup
That’s pretty much it. In closing I want to say that I am only familiar with this material in California. I wouldn’t want to use it where it was constantly raining. I am also not sure how it holds up with snow, although I’d bet it would be fine as it moves with the ground.
Getty museum LA DG path
Calstone Pavers using Slate squares as the 'edging'
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Filed under: Gardening Tagged: | DG Patios, Gardening, Patios
Thanks for the great tips on using DG. I’m mid project and just learning about the stabilizer (and the fact that I laid too much down before the first compacting) Now I’m worried we’ve made a mess of it. I’ve laid down about 3 inches (not yet compacted) of both a path and a patio of gold fines without stabilizer. Is it possible to lay the last 1 inch with stabilized gold fines? Will that help keep down the mushiness in winter? I’d really like a very hard surface in the end.
Thanks so much for sharing your experience.
In your path and patio of 3″, where is your foundation of base rock? I always recommend 3-4″ of base rock underneath the DG.
The base rock is essential really and that too needs to be compacted for a hard surface. The stabilizer isn’t as essential as the compacting process is.
I’d recommend that you remove the DG you’ve put down. Since its not compacted nor stabilized, that should be easy. Just rake it with a dirt rake back into a wheelbarrow for reuse later.
You need to make sure your bed is prepared to the correct depth. You can get away with putting more base rock down and compacting it then you can with the DG. Compact the base rock an inch at a time. It goes much faster with an electric compactor which rents for cheap.
After that, redo the DG in 1/2″ layers, compacting each with the rented compactor. Its not really essential to use the stabilizer. I’m not sure where you live. The drier your weather the better. The farther from the house the patio is, the better. The more drainage you have, the better. I put in a DG patio about 15 years ago in my own yard before the stabilizers were around. It’s held up nicely, but the first few years, after hard rains in Dec. and Jan, the path left footprints. After many years that no longer happened. But again, I also didn’t compact it 1/2″ at a time.
Also, it sounds like you are over using the DG, with as much as 4″! This will make for mushiness no matter when you add stabilizer. 2″ compacted is plenty; even 1 1/2″ is enough compacted finish.
Again, depending on how rainy and your drainage in your area, I’d say 5″-6″ total, with 3-4″ being the base rock and the rest the DG.
OR, why don’t you just rake the DG all up, put down more base rock to within 3/4″ of desired ht., compact that, then put your final DG on top of that and compact it. Save what you’ve already bought in a pile somewhere to add later if necessary. This dusting WILL stay hard, guaranteed, without the stabilizer.
Leslie, thank you so much for your advice. We’re getting our wheelbarrow ready. We live in Kensington (just north of Berkeley) and have clay clay and more clay. The DG is in a fairly flat area with very slight slope away from an adjacent brick patio( that is adjacent to the house). Beyond the DG are two redwood trees and then a more significant slope to the back of the yard. The area where we put the patio and path is very compacted clay and is like concrete. I was advised (now I think ill-advised) that the compacted clay would make a good base and so base rock wasn’t necessary. I can’t believe I didn’t think about the drainage issue (I certainly won’t forget again after many wheelbarrow loads). I’m glad to hear I don’t necessarily need the stabilizer. Luckily we like working in the yard and it’s a great summer to be outside!
Hi Alice, my landscaping work is in Marin County, so I know your clay well. Yes, all my jobs are in clay and although its compacted in the summer, once its wet it just holds tons of water and doesn’t drain, as you know. If you’re not going to use the hardener, probably best to use less DG. If you link to my webpage (listed on my blog at the side as Ecoscapes.net), and go to my portfolio, there is a photo under ‘Tropical: Tiburon Flats’ of a patio under a humoungous Willow tree. Because of their extremely poor drainage (Tiburon flats used to be part of the Tiburon wetlands), I designed that patio with no hardener and less than 1″ of DG. That job still looks great 4 years later and never has been mushy in the winter.
Wow, perfect timing. We just put in a DG patio in our backyard and are having second thoughts. I’m so glad I found your site. We’ve got about 3-4 inches down with no stabilizer. We used a vibrating plate after we laid down all inches. Our concern now is that it isn’t hard enough. Walking across it is fine but our dog wants to dig into it (she thinks she’s at the beach) and if we drag furniture across it it will make huge marks. My husband wants to buy another couple inches of DG with the stabilizer mixed in and use a roller to flatten it out. Do you think this is a good idea? We live in So. Calif in Orange County and don’t get much rain. But they are predicting another El Nino…
Thanks!
Hmmm, I think your problem is not that you don’t have stabilizer, but that you tried to compact it after putting down too much at once. Really, the secret is two-fold: first the base rock is essential, several inches at least. Second, putting down little by little the DG and compacting it, damp, at each 1/2″. My guess is that putting more down over what you have will just make a mushy mess, even with the stabilizer.
The stabilizer is really not a secret weapon. It works just OK. I’ve seen many messes with the stabilizer if poorly laid. Also, putting down a few more inches would probably mess up your final grade height. When planning your patio, you need to plan your final grade FIRST. This also is essential for drainage planning as you need to plan how its sloped, drained, or however you are going to move water off the patio. Even in Southern CA!
Sorry to be a bearer of more work news, but your best bet is to pull up the DG, lay down your baserock properly, and put down either 2″ (1/2″ by 1/2″ compacted) of DG, or 1/2″ without the stabilizer at final grade.
Good luck.
I’ve been told you can use cement in lieu of hardener – seems like it could make sense, but any truth to that an if so, what do you think the mix ratio should be.
Hi Bill, I’ll get back to you on this because I did use a certain ratio once, and had very specific problems. Need to refresh my memory so I’ll talk with my contractor for the details. Check back in a few days.
I have now gotten the skimmy on the cement. We used it in a job last year as it was recommended by a local stone yard and the homeowner wanted to try it. I remembered we had a lot of problems and had to remix it a second time (Dig it all up!) using a cement mixer because the DG and the cement didn’t seem to blend together well.
Talking with the homeowner now, a year later, he says he would NOT recommend it as it makes the DG brittle.
I am not sure where you live, but there is a patented product called Terra Pave that I’ve seen used before for larger applications. It is more expensive than DG but sets up nice and hard, like a natural cement. It comes in many colors (more than DG) and I’ve seen it used in driveways and large walkways. It is a magnificent product.
Essentially its DG with pine pitch as the hardener and it must be applied by someone who knows how. The distributor will come and train landscape contractors on how to do the installation.
I have not personally used it, but I have also heard that it can have similar problems as the hardener does with mushiness over the years. I haven’t confirmed that though.
Good luck
We just had new landscaping put in our Davis Ca backyard. We have a U shaped planter garden box surrounded by DG. Our problem is that the DG has never dried out. At frist we thought it was from over watering the garden and the water wetting the path around the garden. However, the garden has been off for 11 days straight now and the DG is as wet and mushy as ever. After reading your site, might I conclude that it was improperly installed? What can we do now? Thanks for your time.
Hi Kim, I am wondering several things. First, the U-shaped planter box surrounded by DG. What is the drainage like on the planter box? It should have been installed so that it drains AWAY from the DG. Of course, there is always seepage in DG paths, etc. from surrounding plant material, so that might not be the problem.
Second, was the installation done by a licensed contractor? If so, then he/she is liable and must replace/repair whatever isn’t working up to standard.
Third, was the DG installed over 3-4″ of baserock first? If so, that would create some nice drainage. In addition, the slope needs to be correct so that the area actually DOES drain.
The DG should set up within days of installation, esp. in a hot town like Davis. Sounds to me like it wasn’t installed properly and you should take this up with your contractor.
One tip in using a contractor for future reference–always check online to see if their license is active. A contractor can give you a business card with a license number, but it might not be recent and active. There is a webpage with the State of CA that will list active licenses. Let me know how it turns out.
Hi there!
Great information you are sharing here -thank you!
I’m wondering if you have any suggestions for using DG as flooring in a covered dog run. There’s only one dog involved (maybe an occasional foster) and it won’t get high traffic use. More drainage needed maybe? Hardeners or not? I’m in San Jose.
Sounds like a good application. I’d recommend the Strybing Arboreteum method of well compacted base rock, say 4″, then just a light dusting of DG without hardener of 1/2″ to 3/4″. THey have tons of traffic, rain, etc. and their paths are mighty hard. Make sure your drainage is good. You might want to make the middle higher, sloping out on all sides, depending on your site situation.
I just got DG for the floor of a chicken coop, and they love it! . They take dust baths in it and pick grit out of it. I added food grade diatomaceous earth and dried & powdered eucalyptus leaves for mite control.
We left it loose but it’s great to read about how to make it firmer for paths etc
I had to add this here in case anyone has extra DG and also has a chicken or two.
I’m in Sonoma County.
I just finished a project where we installed 6″ of compacted DG over graded/compacted native clay soil (compacted) on a 2 acre lot that is going to used as a heavy construction equipment/material storage lot. This surface appears to be compacted rock hard but in high traffic areas there is a layer of smaller fines (powderlike) on the surface and is causing major dust control issues. Is this normal and is there any way to control/maintain it?
Also, since we haven’t yet experienced a rainy season, I’m concerned about the integrity of the DG following a continuous rain cycle, especially as it relates to the movement of heavy equipment/vehicles across the saturated DG. Do you see this being a problem or is the issue more of a muddy top surface?
Believe it or not, our civil engineer recommended this surface for our use. I appreciate any feedback. Thanks!
Hi Julie, No matter what you do with the DG, there is always a layer of smaller, powderlike fines on the surface. Remember, these are rock fines to begin with. That’s a lot of DG. It might work. I certainly have seen DG used for Driveways and large entrances. I suppose you just have to wait for the rains to see how it works, unfortunately. If its compacted enough, then it probably will. Personally, I might have used TerrePave or less DG.
My new pathway is complete mush!
Of course that has something to do with the typhoon we just had, but it also might have a lot to do with how i put it down. And now I’m wondering if I can properly compact it without taking it all off and doing it again.
Initially, I placed 2″ of gravel on filter fabric on compacted dirt, with trex board as an edge. I didn’t compact the gravel too well, to be honest, and then placed 2″ of the DG on it, compacting it with a hand made wood compacting thing. Since it’s not too heavy it requires a ton of pounding. But it had gotten pretty solid eventually. I sprayed water and let it dry and recompacted it, getting it to where it didn’t indent too much when walking on it. But then the rains came and now it’s way too soft to walk on. I haven’t gotten the paver stones yet due to their cost, and want to be able to walk on it whether or not i have pavers. Can I recompact it now while it’s all mushy? If I could get it fairly tight, I can place brick as a patio/walkway over it until i can afford stones, and that might be a while. But i don’t want it to be so soft. Is it too late? I really don’t want to pull it all off.
any advice out there?
thanks
Jordan
Hi Jordan, Doesn’t sound like you did anything wrong unless you put all the DG done and THEN compacted it, instead of little by little, compacting as you go along. DG will get soft but not mushy if done right. Also, check and make sure you drainage is good.
Wait until it is wet but not mushy, just damp. Then rent an electric compacter and try that. Good luck
Hi Leslie — Thanks for the good write ups on DG. I’ve been trying to locate a supplier for the edging you called out — Ryerson. I libe in Portland, OR and ma struggling to locate a good lucking edging. Any advice would be appreciated.
Thank you.
Hi John, Ryerson header goes by lots of different names. Its basically a steel header, about 16′ long (each piece) with special connector pieces. Mainly look for one that is very thin, about 1/8″ thick. Try Landscape supply houses. You won’t find them at Home Depot.
Hi Leslie,
Interesting to read about your DG experiences. I have a question about using DG as the top layer in a xeriscape garden; so it’s not a patio or pathway that will be walked on. I’d love to hear your thoughts. I helped a friend lay 4 yards of DG on about 500 sq.ft. of compacted soil, and I suspect it will not be stable when the rains come (We’re in San Diego). Most of the garden is quite steep, for one, and we installed a fabric on top of the soil and put the DG on top of that. No gravel and no compacting. Can we expect this DG to run down slope? Do you know of any guidelines for using DG on slopes?
On the other hand, nice blog!
That DG will be full of rivulets from the rain as its not a stable medium on a hillside at all. Don’t forget, its granite, just fines of rock. When you look at a stream, the large boulders are at the top, while the silt, the fines, are at the bottom of the river. That’s why farmland below mountains are so good; all the fines have run down. And that is exactly what you’ll get with your rains. I have used a bit larger rock mixed with the fines for a top mulch on less sloped areas. Call it 3/8″minus mixed with fines and its a good mulch in general and can match a DG patio next to it.
Thanks, that’s kind of what I suspected. I’m surprised that a basic web search on the subject doesn’t yield more informative results. I found your page while searching for DG and slopes (and it’s been mighty informative!), but I was expecting to find installation guidelines. Do you know any good DG references besides folks’ personal experiences?
By the way, I’m intrigued to do the hardening technique on some of the areas of my own landscape, thanks for the personal experience stories, David
Hi Leslie,
What a wealth of information! Thank you. Do you think a 7- 8% slope would be problematic for d.g. – i.e. prone to developing rivulets.
Hi Kimberly, If you like, you could email me, via my ecoscapes.net website, a photo of your site and I’ll give you my opinion. Probably you’ll be okay. I’ve used DG on pathways with that kind of a slope just fine. But had troubles rounding curves downhill where the slope increases. If anything, you might have to add some DG with stabilizer every few years.
Thanks for sharing such a wealth of knowledge! We just installed a new walkway and patio in front of our house with large concrete pavers (cut from an old pad) and 3″ spacers filled with DG. Off to one side there was a large planter against the house that we removed and filled with DG, again to get materials requiring water away from house. Originaly the lawn sloped down to the house and was causing drainage problems. The walkway and patio were supposed to direct the water away from the house. Unfortunately the benderboard separating the DG area from the garden seem to be acting like a dam, holding the rain water that is absorbing into the DG against the house. I hoped the DG would harden enough to sheet the water away, but From the posts here, I am realizing the DG is much more porous than the soil than I thought, and we are still getting water against the foundation. It was installed by a license contractor who convinced us to do less of a grade away from the house than we wanted. Am I correct in thinking that DG installed with not enough grade could hold the water up to the house? I am considering putting concrete between the pavers and a dry creek bed in the planter to direct the water away. We are in the Los Angeles foothills, so most of the year it doesn’t rain but when it does, it is often torrential. In regards to tracking dust and rock bits, yes, the DG tracks a lot and although it is beautiful I probably would not use it again in a walk entrance to the house, even with the 36″x36″ pavers. Any thoughts would be appreciated!!
Go back to your licensed contractor and get him to make things right! That is why you paid him the big bucks for his license and your protection. Not seeing your situation, its hard for me to comment. Did you consider putting in a french drain against the house first, under the patio/walk? This would direct water away and might solve your problems.
One other thing. In general, I don’t like using pavers/DG for patios. Its the inexpensive way to build a patio, yes, but in the end not the best. Either do a patio all DG, or, if you want pavers, set the patio on a concrete base and mortar between the pavers. My reasoning is that you’ll never be able to find a comfortable way to sit and place the chairs, as the legs will always fall in between the pavers, with the DG softer and sinking under the weight. Your chairs can never be level. If you must save money and use DG and pavers, then use large pavers and 3/8″ spacing between pavers. You’ll have to stuff the DG down into those small cracks and it takes time but can be done. That’s probably why your contractor used 3″ spaces, because its easier installation.
DG Road:
We and 4 neighbors have dirt road/driveways/paths topped in DG. As long as the slope is small they are great for foot traffic and for parking. In the heavy vehicle traffic areas they pack down really hard. However now that its been raining for months a thin but irritating layer of mud is pushing thru. Its just where the car tires track. The mud being pushed thru is less than 1/8 inch thick but it tends to get tracked everywhere including into the house.
Is there anything to be done? Could we spread crushed granite (not the decomposed) over these areas and expect the mud to eventually stop slowly pushing thru?
Well, sounds like the DG was laid on dirt. Sure, you can treat that DG as just another layer and lay gravel over the top of it. Crushed gravel maybe 1″ minus or even bigger size, a few inches thick. It will pack down. I think there are as many opinions on this as there are materials. Road base as a top might work as well.
Well, we all really like the look of the DG. It looks classy. Roadbase does not look classy.
The latest DG was laid down on top of some DG done a few years ago. I do not know how far down the dirt is. The mud is really gritty; not slimy. Its almost like all the finest particles of the DG got PUSHED-UP top. Since your post I have found some other DG roads laid down on road base and they seem to have the same issue.
Anyway, to keep the classy look I was thinking about using that crushed granite that looks the same as DG but its just missing the smaller particles. Stone size is less than 3/4″. I was wondering this too would succumb to the push-up from underneath?
Thanks for your posts!
I suggest you look at this solution, http://www.wzsupply.com/products/terrapave.html
This is what I would use for a classy driveway vs. regular DG. I think what you are describing as pushing up just has to do with expansion of the soil, probably clay-based, when its saturated from rains.
TerraPave is basically DG with a pine resin stabilizer. It has a much harder surface finish and MUST be done by professionals who have been trained specifically in its application. It is a fine looking product.
Well! You are talking to the do it yourself queen here! Always look’in for something to do with my tractor. And that web site’s install video is purely for do-it-yourselfers. So maybe I will check that out.
Thanks for the tips.
With all of your experience, I was wondering if you could help me figure out my production rates for the installation and compaction of the d.g. I have a big d.g. job I’m bidding right now. Do you have any figures on labor hours per cu. yd. or per 1,000 s.f., etc.? Any help you could give would be much appreciated!
Depending on the nature of the soil to dig out, adjust your figures. Labor only, not materials: includes prep, spreading baserock, spreading DG and compacting $4-$5/sq. ft.
i am preparing high school track around football field, what is best mixture for compaction. My plain is excavate 8in below finish grade backfilling with 3in of road base compacting in 2in lifts. and then the same process of 5in of decomposed granite is that a suitable depth will this take the punishment of a two day event with grooming any suggestions would be greatly app. or some suggestions to keep cost down its kind of a donation project on my part but want nothing more then to do a spectacular job school has not played a home coming game at home for over 30 years. its time to bring it home for there supporting fans and students thank u for your time j.lee const. sacramento ca.
Hi Jason, I am not familiar with doing a high school track. I definitely suggest talking with your supplier, but here are some of my thoughts:
I feel that you are using too much DG. The more inches you have, the easier it gets mushy in wet weather, even with the hardener. If you use the hardener, the recommended rate is 16 lbs per one yard of DG. At $6.50 pound for the hardener, that can get expensive for an entire track, especially with 5″ of DG laid down.
If I was doing it, I would go for the Strybing Arboretum method I described in the blog entry, which uses no hardener and no more than 1/2″ to 3/4″ DG over 5″ of base rock. You will have to reapply every few years or more, but that’s nothing in costs compared to what you propose.
I just posted a photo for you to see on the DG patio post of the use of DG at the Getty museum. Now I am not clear exactly how they applied their DG, but the look at Strybing is similar. In the case of Getty, its possible that they used TerrePave, which is a fantastic product but even more expensive than regular DG.
Good luck
Leslie,
I am preparing to do a project using the Strybing Arboretum method that you described above (3/4″ dp. compacted DG over 4″ of road base compacted in 2″ lifts). My question is – Should geofabric be used under the road base to eliminate weeds from growing up through the base and DG? Thanks!
Jeffrey
Hi Jeffrey, You won’t be getting weeds growing from under the 4″ of road base. No need for fabric. My experience is that weed seeds blow in, not come from underneath such a depth. I never have used the fabric in this application and haven’t gotten weeds. I have, in only one of my applications that has a fairly shady exposure and next to a lawn (I think there is overspray from the lawn heads) gotten moss growing on top of the DG. Frankly, I was surprised to see that. That was an application with hardener and more DG. With so little DG I doubt you’ll have problems. Just make sure your spray heads don’t overspray onto the walkway or patio and your drainage is great. With so little moisture, there’ll be no base for weeds.
Would you please recommend someone who could install paths on our property. We live between Escondido and Rancho Santa Fe in California.
Zip is 92067
Thanks, Marian
Marian, I would call a licensed landscape contractor. You can go to the State License Board of California, Dept. of Consumer Affairs, plug in the contractors license number, to make sure it is not only legitimate but active. Only use a contractor whose license is active and in the name of his/her business. That way you have recourse if the job isn’t up to par. Unfortunately, I only work in Marin County in Northern California, so I cannot help you with a recommendation.
I have been reading all the postings regarding DG. My question is regarding crushed granite. Does this type of rock exist? All this time I was thinking what I was seeing at our local golf course and in surrounding communities was crushed granite. However, every time I google it I find that DG pops up. I live in So Cal. and visited several rock quarries today and asked for crushed granite but all they carried was DG. Are they the same? If not, is crushed granite easier to to work with ( if it exists)? Thank you for your response.
Hi Michele, DG stands for decomposed granite or really ‘granite fines’. The word ‘fines’ means that its the finest smallest particles when they sift through and sort the granite into different sizes. I am not sure what you are thinking in your mind when you say ‘crushed’. You can get granite in different sizes. At landscape yards they sort rock by sizes for example 3/4″ minus, which means its approx. 3/4″ sizes.
Technically you could use the fines from any kind of rock. I have used fines from other types of rocks, with the hardener, and it works quite nice. The reason you want the fines is that you can get them very compacted. Think about it. If you have larger rock sizes, say 3/4″ minus, those rocks have large air spaces between them so they will move around more under your feet. You’ll never be able to compact that into a hard substrate.
So, to answer your question, when you go to a yard, you need to ask for the size you want, whether it be fines, or 1″, or 3/4″, or 1/2″.
We live in Glendora, CA, about 30 miles east of downtown Los Angeles. We are re-landscaping our garden and plan to have about 700 square feet in decomposed granite pathways and a sitting area. I think a three inch thick layer of stabilized DG should be sufficient (about 6.5 cubic yards) Where would we find the nearest source gold DG?
Sorry but I garden in Northern CA. But your local landscape yard will definitely have the stuff. The gold is the easiest to find in CA. 3″ is plenty and in fact I’d recommend 2″ compacted. More is not necessary better and certainly much more expensive when you add in the cost of the stabilizer.
Hi Leslie -
We live in Sonoma County and have a fair amount of clay in our back yard where we want to put in a dg patio area (10-feet away from the house) as well as some dg pathways. I’m thinking 3″ of compacted base rock followed by 2″ of compacted dg (per your previous instructions). 2 questions: 1.) should I excavate 5″ of native soil before applying base rock and dg and 2.) when you talk about drainage, do you mean installing french drains under the base rock and dg, or do you mean just have a cross slope on the surface of the dg?
Thanks!
On hard clay pan you should be able to get away with 3″ compacted base rock. But since clay is super absorbing of water, you will definitely need to check your drainage. A french drain is NOT what I mean. If you need an actual drain due to your topography, then I would have the patio drain away into a solid PVC drain with a drain box for shrub areas. I don’t like to put drain boxes IN the patio as they are unslightly, unless absolutely unavoidable.
I am not sure what a cross slope is, but you can make you patio slightly higher in the center with a 1% slope all around to drain off. Or you can slope it all downhill. Since I can’t see your yard, I cannot know what to say about that. Hopefully, you have very good drainage elsewhere in your yard, as well as all your gutters draining into solid pipes out to the street.
FYI, I have found that most homeowners as well as landscapers (usually not landscape contractors who know their work) do not properly install french drains. I almost never use that black corrugated pipe as its history in about 5 years. I always use PVC white pipe. The holes need to go face down (I know it seems counterintuitive but these pipes are not collecting water from above. Remember that water always seeks the lowest level). A french drain needs to START at around 18″ below the surface and have a 1-2% slope from there. Many badly done drains go nowhere. The drain needs to drain into something, and that doesn’t mean your neighbors back yard. Either out to the street or if that is impossible, then into a 5′x5′ deep hole full of gravel.
OK, dig your ditch, correct for the slope by hand or with a survey instrument, then fill the bottom with some gravel. Place your fabric in, fill with some more gravel; place your pipe, fill with some more gravel so the pipe is slightly cover; then cover your pipe with your fabric on top of the gravel. Fill the ditch with gravel completely to the top; and don’t plant anything on top except maybe a lite groundcover. Remember, this is a drain and we don’t want lots of dirt going into it. That’s another reason to consider exactly where your French drain will do. If necessary in some spots, you could plant groundcover.
DO NOT, I repeat, DO NOT, use those sleeves that fit right over the black plastic pipes. First, you shouldn’t be using black flex pipe; but a sleeve or fabric directly on the pipe will just clog the pipe in about 4 or 5 years, rendering your drain useless. Do not hire someone who uses that method of black plastic pipe with sleeve. That is the first clue that they don’t know what they are doing. I have seen many fence contractors underbid us by cutting corners; one of the major ones being using this cheap and useless method of drainage.
One more thing. In one of my photos there is a round patio that is one step down. It has a drain in the middle (PVC solid pipe). That was the only situation where I put a drain in a patio and it was because, of course, its a sunken patio.
Good luck. If you need a referral for help, my guys will work in Sonoma County. Thanks.
I’m having a hard time finding anyone who carries the steel edging u refer to for walkways, can u give me a specific name for a supplier?
Since I work in the Bay Area andI have no idea where you live, that’s hard to do. All I can tell you is that Ewing Supply in Marin carries the header. Don’t go to a Home Depot or places like that. You must go to a landscape supply or irrigation supply house that is used by professionals. They should know what you mean.
We need a surface for the drip line of a barn where horses come and go. We live in black clay that will suck you in when muddy, and you sink to your knees.
Would DG be a good surface for this, or do you have a better recommendation. We have tried sand, but the black mud always absorbs the sand and becomes very gooey again.
Thanks.
I would not recommend DG where a drip line of a building is. It will erode and remain mushy. You might want to consider permeable concrete, or pavers set in sand.
Hello Leslie,
Wow, what a great forum! I just laid down 3 tons of flagstone over 4″ of compacted road base and an 1 1/2″ of sand. I was planning on filling the gaps in between the stones with decomposed granite. I live in Galt Ca and found premixed DG with a stabilizer in Stockton Ca. My question is would I need DG with a stabilizer in this application? The cost doubles with a stabilizer and I would just as soon not pay for something without added benefits.
no stabilizer necessary. I hope your flagstone is close. I like to put mine with no more than about 3/8″ spaces, then put the DG down. I know that’s tough to fill as its small but you can do it. You’ll probably need to poke it in, let it set and dry, then you’ll need to do it again.
The reason why I like it so close is because the less space there is between the flagstones, the easier it is to put furniture on the patio. The DG will sink a bit with a chair and its hard to get the chair even. The more flagstone for the chair to set on, the better. For high traffic patios, I usually use a concrete base and mortar joints.
The flagstone is pretty thick stuff and is a select grade. I have some pretty large pieces mixed in with some smaller sizes. My gaps range from 3/8′s to 1″ on average but I do have a few areas that are larger and more closer to 3″. Would you suggest that I try and fill these larger gaps with small pieces of flagstone? Or perhaps it would be good to have a stabilizer mixed with the DG because I have some areas with larger gaps?
Don’t use stabilizer as its a waste. Don’t fill with small pieces of flagstone as it looks like a bad job, or a bunch of mistakes. Fill and compact, fill and compact, then let it dry. It will shrink a bit so fill again to the top and compact. Repeat if necessary. If your 3″ gaps are not in furniture areas, you’ll be ok. Next time cut your flagstone if necessary so that the gaps are a consistent 3/8″ or so. It is a more professional looking job and will make for less ‘holes’, esp. from chairs and the like. Good you used thick flagstone as its set on sand. Thinner flagstone can be used with a concrete base and mortar joints. Thick flagstone must be used on sand to prevent the flagstone from cracking, as well as less shifting. Good luck.
Thanks for the advice Leslie!
I am trying to find out if I can use DG onto of a concrete patio. I am working on a project where over time, layers of concrete were added at different sections of the patio. I am now down to a concrete patio that is 25×15 with no more than a 2″ lip of additional conrete away from the house.
Can I add DG and compact it on top of the concrete? What’s the max depth that I can use the DG with compaction? I have one corner that has a 5″ high area. I was wondering if I can slope the DG to meet the 5″ hight lip.
Christopher, to tell you the truth I have no idea, but if I were doing the job I would do one of two things: If your concrete is fairly even and consistent with few cracks, I would build myself a nice patio, using the concrete as a base. 15′ x 25′ is a nice big patio. DG is how you go when you don’t have much money for a nice patio, or if you need the permeability like under a tree. One of the major expenses for a patio of flagstone is prepping and pouring the concrete pad. If you already have a nice pad, why not mortar flagstone on top of that? Its a job even you could do without a contractor. Just rent a stone saw and you’re in business with a helper or two.
Personally though, if you were committed to DG and I was the design supervisor, I would remove the concrete and do the DG right the first time. You can check with the supply houses, but I suspect it won’t work and that’s because where is the water going to drain to; what’s going to happen when the DG wants to shift as there’s no give underneath. Sounds like a losing proposition intuitively. I would go with nice flagstone, something like a 3 rivers or another Montana stone, and mortar the joints.
We are putting in a new school garden in San Jose CA, we had terrible crab/bermuda grass mucking up our beds. We couldn’t win that battle so we ripped everything out and we are starting over from scratch. Here is my question. We found Quarry fines for a fraction of the cost of DG. It is even cheeper than base rock. So can we use Quarry fines in place of DG and can we use it without putting in base rock. My understanding of base rock was that it’s use was to save money. Since the Quarry fines is so much cheeper than all of that, we want to just install 6″ of quarry fines. What are your thoughts on this? Thanks for any response you may have.
DOG PARK PROBLEM in Arroyo Grande Ca
Hi (Great subject and advice)
I am a volunteer/board member at our local dog park.
Our once beautiful grass area is completely destroyed.
The park proved more popular than we expected.
We would like to cover the area in DG, if we can raise the $$ (Totally financed with donations)
Looking for any advice/suggestions.
The large dog park is about 4/10 of an acre. The shape is odd–but it’s 253 feet long. Because the width varies–we could estimate an “average” width of 68 feet.
There is about a 6 foot drop from the to top the bottom of 253 feet.
We have a city supplied sprinkler system.
The area is now in Crab grass and mud, lots of mud LOL
Many thanks both for your above and any future advice.
Carl
Senior citizen,
I’d do more research before I committed to DG if I were you. Dogs are tougher than people on softscapes and although DG works great at lots of public places, those people aren’t playing football on it either.
Frankly, you might want to look into fake turf. Dogs can pee on it and high school teams play on it. Its pricey but lasts for a long time, no mowing, no mud, can be rained upon and always looks good. Talk to a few companies that sell it and ask their advice for this application. I think it would work great. I’ve installed it only once per my clients request. They have a dog who hangs out on it constantly. So they clean up the poop on it, then just wash it down.
Research is the key, thats for sure.
There is an outfit in Texas that has a super turf.
It would cost us about $70K
Took us 4 yrs to raise $50K for Fensing, sidewalks etc
We have (almost) desided on Bark.
Bark for our Bark Park.
Many thanks
Bark is good. You might check with some outfits to see if they’d donate some fake turf, as a ‘test’ and ‘promotion’ area. My client somehow got some free leftovers from a job. He had a small front yard. Maybe some of these companies could see it as an advertisement as to its viability with dogs in people’s homes. It would be nice to have some bark and an area of curved ‘lawn’ as well. Might be worth the try.
I found this article while researching DG patios. I want to use it as a patio. Most of your posts are from California. Wondering if you have any information about this kind of patio in areas with lots of snow. The snow sits out on the north side of the house from November to March. I need good drainage in the spring (mud season) and so gravel or DG would be preferred (think). The rest of the year we get very little rain (high desert at 6300 ft). It is cold in the winter with January lows reaching -20. What do you think? Thanks,
Hi Kathleen, Its difficult for me to answer that question. If you do research, as you’ve done, on DG, you see that its main drawback is what happens in wet weather. So you’ll see recommendations like “don’t put it under a roof drain” or “make sure that your area drains well”.
Since I have lived part time in WY, and I see you are in Colorado, I am encountering a lot of issues with the Bentonite nature of the soil in my driveway. My drive is also on a slope that drains into a marshy area. In cold weather, when the grounds’ frozen, of course it’s fine. But as the ground thaws, it ruts terribly. I raised the driveway last year with limestone from my hillside. It still didn’t help. Most people here recommend adding lots of gravel. But that gravel will just disappear into the clayey soil and I’ll have the same problem. I talked with a fellow who took a local soils class re: construction. Bentonite is different than the clay I dealt with in CA. Its way worse. Its slippery when wet and sticks like anything. The class suggested putting sand down first. The sand gets into the pours of the clay and binds it. This makes sense to me. Lots of homeowners in CA think that the solution to clay soil is to add sand. OMG, that’s the worst thing, as clay and sand is the basis for cement. But in this case, that’s what I want. So I’m going to lay sand first, then gravel and/or baserock over that. That combo should keep the gravel or baserock floating on top of the sand/bentonite mix.
All this is to say that “I don’t really know” in terms of your situation. It would depend on your drainage in general. I suspect that DG is not a good way to go in this situation, but if your drainage is ok, and you stay off the patio until things get drier in the late spring, you might be okay. What you could do is put down the baserock (I do know that in snow situations you’ll need MORE of a base, so I’d do 6″ of baserock, or road base as it’s probably called where you are. Then try the dusting method I recommend. By doing it this way, you won’t have a great outlay of $$. And if the DG doesn’t work, then you still have a nice base for a flagstone patio.
That being said, if you want a concrete patio in the end, you would have to remove some of that baserock, but not all of it. You’d have your patio leveled correctly and probably could pour about 2″ of concrete over the base.
Essentially, I’d go talk with the local yards and see what other peoples’ experiences are with using DG in your area. Keep in touch as I’d be interested in what you find and your results.
Project: I am installing a curved flagstone walkway from the concrete driveway to the raised brick front porch creating a 21 foot by 12 foot raised flower bed between the house and the walkway, in Denton County, Texas.
Status: My trench is 45 inches wide, 6 inches deep, and 36 feet long. The flagstone and crushed granite was delivered by a local hardscape company just before the rain filled my trench. I extended my gutters across trench, used a sump pump to remove the water, but the trench is still muddy.
Q – 1. Do I need to wait until the base of the trench is a dry and has a hard base before spreading the granite?
Procedure: I plan to: install 4 pieces of 2 inch pvc pipe with duct taped ends for future sprinkler system/lighting repairs across the trench below the trench bottom, plate compact the dirt, spread 2 inches of crushed granite in the trench, sprinkle with water, and plate compact granite base, install 4 inch steel edging from Lowes for my 42 inch wide walkway on top of the granite base with a 1/4 inch cross slope away from the house, backfill the edging with dirt and compact with my shoe, spread 2 more inches of crushed granite between the edging, sprinkle with water, and plate compact, position and level the washed flagstone in the walkway with 1 inch to 2 inch spacing to match the front porch columns, broom crushed granite between the stones and sprinkle with water, and sweep additional granite in spacing if necessary.
Q – 2. Do you have any corrections, suggestions, or improvements to this plan?
Thanks for your assistance,
Ken
Ken, you sound like you know what you’re doing! I’d wait till the base is dry to begin. Go for it…
Hi Leslie:
I live in the Oakland hills. I am wondering if laying down the steel or trex edge around an exiting old cement path and patio and filling with DG would work. The re is a slight slope to the property and I do not think it would become a mushy mess as described about by people. My question is dose cement make for an ok DG base? It is not a heavy used path–or patio. I just think it will look beautiful and I could install stepping stones in the walk on top of DG to add flare and make a stable spot to step.
What do you think?
Thank you!
Hi Emily, Drainage is the obvious issue. With the permeable base rock underneath of several inches, water has somewhere to drain too before it runs off. With concrete, the water would be draining (assuming there is a slope to the concrete patio) directly underneath the DG as it moves off the patio. Plus, with all the ‘dirt’ (DG) on top of the concrete, it would be draining really slowly. Think about it: you’ve seen old patios with dirt on top. The concrete stays wet underneath for a lot longer. With baserock underneath, the pores allow the water in the DG to ‘wick’ away as it drains off. I would think that it would create a problem for the DG, leaving it soft.
If you have, already, a concrete patio that is not cracked or uneven, and in good shape, why not do something with that. You can add color to the concrete. The way they do this is by adding a thin layer of concrete called a ‘slush’, which can be in any color you choose, even ‘DG color’! Or you can use your base for pavers.
Another idea I’ve used in my own yard is to break up the concrete patio and reuse the concrete as a ‘flagstone patio’. In other words, break the concrete up in largest chunks and reset it. I did this in my own yard and here’s how: I used about 2/3 reused concrete and 1/3 flagstone pavers of my choice. I set the patio on sand and grew plants in between (or you can use DG in between). Before planting I ‘stained’ the concrete with an iron oxide mixture. This is purchased from nurseries as its used normally as a supplement for plants. Its very cheap.
Take the iron oxide and mix it with water into a thick paste. Use gloves as it stains hands, clothes, everything. Spread it thickly on the concrete and let it set and dry. The longer it sets up, the darker the color. Usually about 1/2 day. Then just wash it off. Be careful not to get it on plants as it will kill them at this strength. The color is a wonderful golden rusty brown, like the California hills in summer or the old mining areas around CA. Over time, like about 3 years, the color will fade and you’ll have to do it again if you want the deep tan color. But this is a cheap solution to many problems, plus it recycles your existing concrete (although not all of it will be needed for the patio).
Note, I added a photo under Patios hard and soft
I’d stay away from putting DG over the concrete patio, unless you have $$ to play with and want to experiment.
Hi Leslie,
I have read and learned quite a bit about DG over the last two weeks. I intend to lay a 80 sq ft DG patio in a not so traveled area. The depth of the area is 4 inches from the ground to a surrounding concrete level pool surrounding (and wall on other sides). I intend to compact 2 inches of base rock and then lay 2 inches of stabilized DG on top. My plan was to wet and compact the DG in 1/2 inch layers. After reading this thread, I am curious if wetting the DG is necessary. Should I simply compact the DG (which is powdery/dirtlike)?. It has been my impression that without water, the DG will remain powdery. I also intend on installing drains in a couple of out-of-site areas.
One additional question: Is it recommended that the final DG surface be raked for appearance sake (slightly loose looking rather the hardened look it has after watering and compacting ) or will that naturally occur over time. I am happy to send a photo of the area if possible. Thank you.
Yes, you need to use a ‘spritzer’ on your hose, and dampen the DG. What you should do is dampen the DG in a wheelbarrow so it is moist but not ‘wet’. Crumbly. Then spread it over your base rock with a dirt rake, even it out and use your electric tamper. So each layer needs to be dampened as applied. Make sure you order your DG with stabilizer if you’re using 2″ total. If you can’t get it pre-mixed, then you’ll have to mix it. I have heard that the most efficient way to mix stabilizer with DG is to order a small concrete mixer. That way you are sure to have it evenly mixed, and damp as well.
Once the DG dries, small bits of granite lie on the surface. This is normal and the reason not to put DG next to a house entrance so you don’t track it. I suppose you can rake those fines if you want. That is a very ‘Zen’ thing to do! If you want to send a photo, please send it through my Ecoscapes.net webpage. Thanks.
Leslie,
Thank you. I have two follow up questions. 1) How long should I wait (after spreading the wheelbarrow-moistened DG) before I compact it (immed or several hours later), and 2) Do I apply more water to the pre-moistened DG after it has been spread.
Thanks again,
Paul
Don’t wait, just begin compacting little by little. Its just damp dirt!
After you’ve finished completely, you might want to spritz it down, maybe try tamping again the next day or so. But that’s all. You’ll know if you’ve compacted it enough.
Hello Leslie,
Excelent discussion you have going here!
We are building a dry-laid patio (on top of about 3″ of crushed rock and 2″ of sand) in Northern California (a no-snow area near Sacramento). About 175 sq. ft.
We have many DG paths in our community and I know that water tends to drain off it rather than down through it.
We are patio virgins, working with Arizona sandstone about two inches thick, and couldn’t always get the rock to break exactly the way we wanted. We wound up with some fairly large gaps between stones.
We can fill in the gaps between the flags with sand or DG. I reckon that DG would be less hospitable to weeds and to local (Argentine-type) ants. Is this correct?
I also anticipate that DG will NOT drain as well as sand, so I am looking for ways of facilitating drainage down through the DG after it has hardened. I am thinking about driving some hollow aluminum tubes (1/2″ diameter?) down through the DG and into the sand/gravel layers below, and filling the tubes with coarse sand.
Do you think there is any merit to this idea?
Thank you!
First DG is a lot less hospitable to weeds. Though over time you’ll get a few blown in. Where are you at with the patio? You need to plan the patio, any patio for that matter, with fall to drain into shrubbery drains that you set on the outside of the patio (you can set them in the patio but I don’t like to do that because it looks bad). If you haven’t done that, you should pick up your stone and re-grade the patio to several outside drains. Then I’d relay the stones so they are closer if you like. Sure, they don’t need to be closer but you’ll hate putting furniture on those big cracks.
You can break the sandstone by scoring it first, then it will usually break along the scored line. Also, you are going to have so little DG in there that it will probably drain fine down to the gravel/sand layer.
Another alternative is to grow stuff between the cracks by filling with a sandy loam mixture. Your local Landscape yard should have a special mix that is very light for that. If you choose to go that way and you are in sun (I assume your patio is in sun), then I’d use Elfin Thyme. Its very attractive, extremely flat, and low water.
Hi leslie –
I find your blog here very informative. we are planning on doing some DG walkways and a patio area, and I am planning on using the method you talk about with the 3-4 inches of road rock with 3/4 dusting of DG. I have a very small narrow backyard so my initial plan is to have 3/4″ quartz rock on either side of the DG pathways, my question is will i need a boarder between the rock and the DG and can you suggest a cost effecient type boarder that would still look attractive?? and the other question is i have seen on some diy sites where they put down a weed barrier first..is that necessary if I am using the road rock base??
thanks for you help!
Yes you will need a border, essentially something to contain the DG. The least expensive border is landscape plastic borders. They are very flexible, not super great looking but your rock will probably hide it sufficiently. Plan so the border is basically flush with the DG and the border will just disappear. The border just keeps the stuff from dispersing.
RE: weed barriers. Personally, I think it almost all instances a weed barrier is a waste of money. Possibly if you are just laying down cobbles, then its useful. But weeds don’t come from underneath. Remember, you’re laying down 4″ of road base. Weeds BLOW IN as seeds from surrounding areas. I almost never use a weed barrier.
Hi Leslie,
I can’t believe how generous you are. Just stumbled across your blog—very gratefully. Check out our website and blog, too—and see how aligned our vision is with your “human footprint.”
We’re creating a labyrinth in our backyard—as an homage to , labyrinths, stone circles, and walking meditation around the world. So after finding your blog, we’re going to use the Strybing method you describe for the labyrinth paths (we’re in San José CA). And we’ll use fly-ash pavers for the lines outlining the paths. You might want to check out these CalStar pavers—green-wise.
http://calstarproducts.com/sustainability/
My question since: we’re thinking that since the overall circumference of our labyrinth will be comprised of these 2″ high pavers, that we won’t need a Reyerson or plastic header to further contain the compacted top layer of DG. Do you think that’s right? (we’ll be cutting some of the pavers in half intermittently to help us achieve the curve—and we want the labyrinth lines to be a little ragged/imperfect).
Thanks so much for your vision—and generosity.
Chris
Hi Chris, You and your husband are doing some really interesting work. I’ve walked many labyrinths and thought about creating them. Your vision is wonderful.
Although I’m no fine artist, I’ve been enjoying experimenting with found natural materials for paints–painting found skulls and hide. Talk about an earthy, connecting process!
Now to your question. I think the pavers would work as an edging, as long as there are no gaps or cracks that the DG could seep out of.
This is what I’d do: Dig out my entire circle first to the depth needed for the baserock (which is more than the depth of the bricks. On the surrounding soil of the circumference, lay out my brick edging to finished height. Hopefully you have clay soil. Then I’d use Portland cement generously directly onto the dirt and cement my outside layer down. Put down the baserock over the entire circle, then lay out my bricks for the path labyrinth. Don’t cement these. Just lay them out then fill with DG and tamp. For the bricks in the center, it doesn’t matter if there are gaps or the DG leaks because its all DG. But you want to make sure that your edging of bricks has no gaps. The cement will help that and also help hold them in place.
If you use the dusting method, are the bricks supposed to be flush or elevated? Make sure you account for that because that would mean you’ll have to lay those bricks in the center down when you are doing the baserock. Be careful tamping because I don’t know if they will crack when tamped down with the electric tamper. I bet they will.
I’ll post a picture slightly unrelated of a calstone patio we did with an edging of slate. Calstone needs to be contained as well. In this case we didn’t use a header, but used the slate as the header. The slate was also cemented down. The slate being a different thickness, it took some attention.
Hi,
I live in Oakland. What is closest resource for decomposed granite.
Thanks, Ravi
American Soils Richmond. They deliver.
Hi, Leslie – the site is amazing… the advice is amazing.
We have a very small patio that right now is flagstone surrounded by elfun thyme but it is all very unstable.
I was thinking of creating a DG patio, but wanted to make sure I understand your advice as I read it for optimal results:
- Put an edge around the patio to hold everything
- Create a base of 4-5″ of “base rock” (is “base rock” gravel?)
- (Can I put landscape fabric under the base rock?)
- Put 2″ of stabilized DG down, 1/2″ at a time, keeping the DG somewhat moist and compacting every 1/2″
- I assume before I put the final 1/2″ down, I should lay the flagstone down, keeping the gaps to 3/8″ or less?
- Put the final 1/2″ down around the flagstone??
Do I have the basic recipe correct? Would greatly appreciate any corrections because I have the luxury of not having started the project yet!
And any suggestion of where to get stabilized DG in the Los Angeles area?
THANK YOU!!
Dan, sounds like you are redoing your flagstone patio. Flagstone patios are usually set on sand. That is because flagstones are not even thickness and the sand allows you to fudge each stone. Then you fill the spaces with loamy soil to grow stuff in between. If you have a natural hard base that drains well, you don’t even need baserock underneath. Question is…who set your patio to begin with? Was it the homeowner previous to you? A professional? Doesn’t sound professional if its not stable. A good contractor can evaluate your base underneath and what you’ll need…existing soil or baserock.
Flagstone can also be set directly on baserock, with a DG layer underneath. You’d use a thin layer of DG not compacted, just as a means to level the stones. Then stuff the DG into the 3/8″ gaps.
If you want to grow stuff again in between, then although lots of websites suggest DG for growing in, I wouldn’t go that route. Make your spaces bigger for plant material, then use a loamy sand in the cracks. DG is basically crushed granite-rock-made into fines. There’s no nutrients to speak of in it except some minerals…no nitrogen etc.
As far as fabric, sure you can do it but its a waste of money as I’ve said before. Weeds are not going to come up from below your base rock. Weed seeds will blow in and no fabric can prevent that.
If I were you, I’d consider putting down a real patio. That means, laying down a concrete base and mortaring the flagstone. I really don’t like to use flagstone and DG together as a patio, nor do I like patios with plantings in-between. Its okay for a small area where you won’t be sitting much. But for real use, a mortared patio is the correct way to go. Or since you say your patio is small, why not chuck the pavers and just do DG, using my dusting method. That will definitely be stable.
My wife really wanted the look of elfun thyme in between the stones… we put in the patio. So it’s a very non-permanent structure that we’ve found is really inadequate. It’s not a large area and we’re not in love with the idea of pouring concrete, so we’d like something a little less permanent. We don’t want to grow stuff in between – we think that’s led to the instability.
So what we’d like to end up with is a small, stable patio that can support our outdoor table and chairs on a level surface.
So knowing that’s our goal, does it change your advice?
Thank you very much for your detailed and thoughtful reply.
Why not look at the photo in my latest post of the small DG patio with a few pavers stuck in for decoration. If you must go with DG then that could be an option.
I didn’t say a concrete patio, I said you should pour a slab and then put your pavers down for optimum drainage and stability and long term use.
The reason I don’t like the pavers/DG idea for a patio with chairs is that your chairs, unless they are heavy legs and the flagstone is close, will stick inbetween, at times, the cracks. Its uncomfortable for women with high heels too. If you don’t care about those things, go ahead and use my above suggested method. DON’T put down 2″ of DG in that case as that’s for a DG patio and will just destabilize the pavers. Just put enough, on top of the baserock, to fiddle with the pavers for leveling, then put DG in between.
Growing stuff between the cracks will just lead to endless weeding (although Elfin Thyme is the best choice. I applaud you on that one); you’ll have to make your cracks bigger so more chance for heels and chair legs getting stuck.
Sorry to be dense, so if we wanted to try this again…
- do about 2″ of gravel
- put down about 1/2″ of stabilized DG
- level the stone
- put DG in the cracks, trying to keep cracks to 3/8″ or less
I realize this isn’t optimal according to what you shared, but probably better than what I have now (?), which is primarily not working because the gaps are bigger to get the elfun thyme room to grow, but that creates issues for chairs sinking in between the cracks.
What do you think?
No, you need a better base than 2″ and don’t use gravel. I said to use baserock or sometimes called road base and use 4-5″ depending upon the hardness of your subsoil and the amount of rain you get. The stone itself is around 2″ so that makes about a 6″ prepped area. 6″ is about the same you would use if you had used only DG. Why don’t you watch this video on the web…http://www.chacha.com/video/172961414/how-to-make-patio-pavers-and-walkways. See how he uses the DG just to get a level walkway. Since he’s making a walkway, he’s only laying it on dirt below. A patio is a lot bigger, needs good drainage and stability so you use road base below. Make sure that you keep a slope for drainage! You are going to use about 1/4″ per foot (1″ per 4′ or you can even get away with slightly less if the patio is really small). Drain to outside shrub drains is the best.
FYI, I don’t think your cracks are getting bigger. Pretty hard for the thyme to move the pavers. Its just that the thyme is spreading over the pavers.
Also, make sure the stone you use is thick and not some thin type. That’s because you aren’t mortaring it down so it will shift.
For walkways, I’ve mortared down stone on hard clay ground then grown stuff inbetween. You just throw the concrete onto the dirt and place the stone. Its not fool proof but a better way to do a walkway when you want to grow stuff in between. I’ve done this in front walkways even. Just know that when mortar is put in between joints if done this way, the mortar will definitely crack.
that’s a 1/4″ fall per foot. You can get away with 2″ per 10′ as well.
Thanks – I’ll watch the video.
We have fairly wide gaps between the stones (deliberately) so that the thyme would be a prominent feature… works out nicely as a visual but not in practice of sitting on a chair, which hits the thyme and sinks in.
And then to top it off, it appears we probably have a mole, so the thyme has gotten “pushed up” in a few places, too.
I live in LA, so not too much rain… and we have very good drainage in the yard (thanks to bringing in a big contractor to do a ton of drainage work).
Thanks for all the advice – I look forward to watching the video.
I have a friend who has a granite countertop company and they have small pieces of granite and some of them are as big as my hand. can i use them and if so how can i grind them and is it safe for gravel too?
aren’t they sharp?
Hi Leslie,
Thanks for all this info. I am starting a DG walkway next week and based on your the info here, feel confident it will be a successful project.
Question: My property in downtown Sacramento slopes about 3 feet front to back. What method do you suggest for getting drain water out to the street?
Thanks Greg.
Frankly its impossible to talk about drainage without looking at your site. Are all your downspouts hooked into a drain? If not, that’s the first thing to do and keep them separate from any landscape drains. Other than that, have a reputable contractor look at your drainage. Don’t use him if he suggests using 1. french drains made with black flex pipe….use only white PVC drain pipe as it will last or 2. he suggests black flex pipe that comes with a drain sock. French drains need to have gravel above and below, then the fabric, then more gravel on top. If a contractor is doing those methods, he either doesn’t know what he’s doing or is cutting corners for a bid at your expense.
Leslie-
You are amazingly generous! This site is great. We live in Pleasant Hill, and are putting a 100% edible garden in the back yard. I have cut the paths, and my husband is about to start putting in the base rock. We will put in 4″ of base rock, but are suddenly a bit shy about the DG. We had intended to add 2″ of DG. There are two sections of path that have a slight slope (1 is about 3″ over 10 feet, the other is about 3″ over 7 feet). Do you think it migrate downhill on that gentle of a slope? I have just come up with a brainstorm of putting flagstone down on the sloped areas only, morphing to just DG once the paths are flat.
So my question is this: how much slope can DG tolerate without rolling downhill?
thank you SO much!
-Patty
Hi Patty, hope you looked at my post on edible landscapes. Probably you’ll be just fine with your slope as its not much. You may have to do some fill in after the winter rains every few years.
We are thinking of covering about a 500′ sq yard in flagstone w/ dg (instead of grass, which the dogs have destroyed).
is it best to do road base, then sand then dg in between (yes we will keep the gaps tight)? Do we need stabilized DG? We don’t want th dogs (or anything else) digging out bits of the DG.
Also, does anybody have experience w/ DG and large dogs??
THANX!
–c
in my experience you can use either sand or DG. No stabilizer necessary. You don’t need much sand/DG on top of the road base. Just enough to level the flagstone. Sand is cheaper.
If you have flagstone then you’re not going to have much DG so why worry about the dogs messing it up.
Thanks so much for your quick and helpful answer! We have one follow-up: do we need to break up the dirt at all… we were considering a tiller, but obviously don’t want to if we don’t need. We live in the San Fernando Valley in SoCal, so the dirt is fairly hard/clayish.
Thx again!
–c
DO NOT TILL! When doing a path or patio you want that hardpan underneath. Sure, you have to break up the ground for your base, but keep it as hard as possible underneath. Just pick or shovel it to 6″ below finished grade and go from there.
We are using DG for ~ 15,000 residential sq ft of xerascape / desert landscaping in Reno, Nevada. The front yard is ~ 5,000 sq ft in two sections with the remaining 10,000 sq ft in the back yard. Almost none of the finished area will be walked on, so footprints / mushy surface is not an issue. We noticed the delivered DG sets up extremely hard once it’s been watered, so rain / snow should stabilize the covering. My question is how critical is it to compact the DG on this large an area during the initial installation. Thanks, Craig
Hi Craig, well I cannot answer your question because I have always compacted DG, whether by machine or hand. Since you live in an area with relatively minor rainfall and therefore run-off, I’d ask your supplier about that and their experience.
In addition, I think that you might consider your liability if it doesn’t set as specified in your contract. I sure hate coming back and redoing what I’ve done in the past with all that added expense coming out of my pocket. I would say “Better Safe than Sorry”. Good luck.
Hi Leslie,
Thanks for the quick response! This is my personal residence. I was hoping to get some tips on spreading the DG – compacting vs not compacting. I could rent a 2ton dual-drum compactor but am not sure if this is overkill. hand compaction seems like it would take a long time.
Like I said I’ve never not-compacted DG. Even in the ‘ole days, before the stabilizer, we hand compacted it. I would suspect that, just like laying down gravel fines, if you don’t compress it somehow, whether by car or by machinery, it just is loose and eventually goes away, pretty easily.
Personally, if it were me, spending all that money on DG, I’d compact it!
Hi Leslie,
My house backs up to a creek and I want to have a path from my back patio to the water (about 75 feet from the patio to the water).
Do you think a fine gravel would be more durable, and can I get a similar look to DG? I was thinking of laying the gravel fairly thick; 6-8inches?
I’m in the sierra foothills and we get a lot of grasses between my huge oak trees, and I’m afraid DG would not be as durable as gra
When I lay a gravel path, I don’t want it that thick. What we do is put down 3-4″ of baserock, then just about an 1″ or so of gravel. If you lay it down thick, you’ll just be sinking when you walk on it. You’ll get grasses either way because the grasses seed from above, not come up from below if you are laying a 5″ foundation. I suppose you could try some weed cloth but I never use the stuff except sometimes between dirt and larger cobbles.
Hi Leslie,
You have an impressive track record, not only with your DG advice content but also with the steadyness of response. Thanks for that.
My DG question relates to it being used as a surface for a petanque terrain. In case you are not familiar with this game, it is very similar to bocce but with origins in France instead of Italy. The balls (boules) used are steel and weigh about 1.5 pounds. They are often thrown such that they drop to the DG playing surface from a height of 2 to 3 feet. After just a couple games (~40 minutes of play) the most heavily impacted areas of the terrain become soft and loose, which changes the character of the game quite a bit. I would like to have the terrain remain much firmer with just a minor amount of loose particles on the suface.
My terrain is 10 feet by 40 feet, bordered with landscaping timbers and was constructed by placing 4 to 6 inches of compacted Class 2 road base on compacted native soil to create a level subgrade and then topping that with 5 to 6 inches of DG. All materials were placed using a viratory plate compactor in ~2 inch lifts.
Will the addition/use of hardener in the DG improve my situation? If so, would you kindly suggest how many pounds per CY or ton that might give the best results? I suspect you might suggest that I reduce the DG thickness to something less than I have already installed, but I think that a very thin layer as you have suggested for other applications would lead to ongoing maintenance headaches.
Thanks David for the support. Interestingly enough, my main intent with this blog wasn’t DG patio advice, but to describe what its like to live close to the natural world. Living most of the year now in the Greater Yellowstone Ecosystem is a wonderful experience…the only complete ecosystem left in the lower 48. I’d hope to ignite peoples interest and love of the land through this blog. You only protect what you love. I’d hoped to inspire people to protect our last bits of wildness.
That being said, I’ve given the suggested pounds per yard in a previous response (1/16/2010). 16 pounds per 1 yard of DG is what is the recommendation from my landscape yard in Northern CA.
So, my question is: you’ve already compacted 5-6 inches of DG, you said. How can you add hardener after the fact? I once came to a new clients house. Her gardener had built some steps of PT wood with DG on the runs. Since he didn’t put hardener in initially, the DG was squishy. So he tried adding hardener after the fact…ugh, what a mess. Simply put, that doesn’t work. We needed to take all the DG out and begin from scratch.
Unless you are planning to remove all that DG and remix it in a mixer with the hardener, don’t bother. And if you are going to that trouble and the client is willing to pay for the labor/materials, You might want to look into the TerrePave material. Of course, I am not familiar with this kind of use for a DG situation. But I do know that the TerrePave sets up very very hard. As I’ve said in past posts, it is DG but mixed not with the regular hardener but with a type of pine resin (I know its resin and think its from pine). You must be schooled in how to install it, but the yard I know of in Santa Rosa, CA will send a man out to instruct you in how to install it the first time. I would at least call up Wheeler Zamarroni and get their opinion on this as they would know more about its use for this application than I would.
Meanwhile, I hope you enjoy some of my other posts on living in the real wilds, as opposed to creating wild lands in our backyards (which is also absolutely necessary in our cities and burbs for wildlife habitat and human enjoyment). Best, Leslie
Hi Leslie–
What a great site–and you are so generous with your great advice.
We live in Rocklin, above Sacramento. We have a great new patio (made of Azek) and below that, existing DG paths through our garden.
Our landscaper (licensed, of course) is remodeling the back and front yard. He mentioned that he could harden our DG pathways by sprinkling mortar on them, raking it in well, sprinkling it with water, and then tamping it down. Have you ever heard of this technique? Reading over your posts, it seems that there really isn’t any way to harden an existing DG installation.
Thanks!
never heard of this technique. See post 8/16/09 for my brief (and never repeatable) experience with concrete and DG (Concrete and mortar are essentially the same thing). I would suggest you tell him to do a test area first and live with it for a while (in case you have the experience my client did). If it works, let me know.
I’ve been reading your blog on decomposed granite regarding a hardener additive. I may have missed it, but I’m not seeing the type of hardener additive, and where it can be purchased.
I’ve checked with Lowes, and they are not aware of such an animal. Perhaps it’s a concrete hardener?
Also, what do you suggest for compacting? Thanks!
Well, Lowes is obviously not the place to buy decomposed granite then. No, it is NOT a concrete hardener. It is actually a type of resin that binds the DG a bit better. You really need to go to a landscape supply house. Where I live in the Bay Area I’d recommend Shamrock. Go to a professional house if you want a professional job.
Just for an aside…when I come into a job where the homeowner has done the irrigation, the supplies are usually from a Home Depot type store (Loew’s etc) The irrigation materials from these houses are not quality, and they are also not standard. For instance, a 1/2″ drip line is NOT 1/2″ but less and takes wonky fittings that aren’t standard. Professionals will go to an irrigation supply house and that’s where I recommend do-it-yourselfers go. That goes for lighting supplies as well. Obviously, from what you tell me, it goes for Decomposed Granite supplies too.
As far as compacting goes, you can use a hand compacter or rent an electric (much easier for bigger jobs)
The above information is excellent. I read most of it and found it very useful.
I have a corner lot and I am planning to install a second driveway on my back yard for storage of my travel trailer and for access to my shed. The size is approx 10′ x 35′. I also plan to make some small walkways around the back yard and put grass on the remainder.
I would like to install the DG and road base that you mentioned above. Trouble is no one knows what DG is around here (Newfoundland, Canada). I checked with a local gravel / sand supplier and the do supply crushed granite of various sizes. I went to the place and took a few samples. They described it as a “washed middle-coarse sand” where they separated out the larger crushed chips. Does this sound like it could work?? I have a few pictures I could email if you have an email address. Would appreciate if you could have a look.
FYI, I have used several other different kinds of rock fines as a substitute for decomposed granite. What you need is a rock that you like the color, and then you must be able to get it as ‘fines’. Sand is just not the same as crushed fines of rock. Sand grains are too big to compact tight. You should be able to find a good substitute in your area. We all just have to use what we have locally.
[...] DG Patios–Decomposed Granite « The Human FootprintTips For Using Decomposed Granite During Your Next Remodeling Project! … Decomposed Granite Cost … If you are curious about what the decomposed granite cost would be to have it done to your home, it will depend on what type you choose. The cost also depends on the amount of area that needs to be paved. The cost for a… [...]
[...] DG Patios–Decomposed Granite В« The Human Footprint Jul 10, 2009 … I thought I'd do a post devoted to that with a few photos. ….. Could we spread crushed granite (not the decomposed) over these areas and expect the mud to eventually stop slowly … [...]