Like all new things, it takes a minute before you realize the long term results. Stays slightly flexible so it doesnt crack ((yes.it cracks, sometimes)). Really, do we want to build plastic landscapes? Stone thicknesses range from 1 1/4 2 1/4. Stone dust getting kicked out of the joints may be a bit of a concernbut I would fill with stone dust, hose down, and then top it off. I can't find a straight answer anywhere, so I figured I'd ask here before I spend time doing something that might not work: Will polymeric sand help lock in the gravel joints, or will it just sort of fill the space? I don't think he was looking to make bumpsjust kinda level it outoysorry..lol, you so funny! I just put down some pea gravel around my fire pit area and now anytime someone walks on it the gravel gets into the mulch and all over. The contractor used a Portland lime & sand mortar beige color by Spec Mix between the stones. Yea, hardened into something spongeythats a polymeric sand type material. It looks pretty cool as well. To keep pea gravel from rolling and shifting, tamp it down with a heavy lawn roller or hand tamper after you install it. Cool, Im glad that worked out from youand Ill use those two flagstone photos, for next time someone asks a similar question. Pea gravel can be found in many kinds of landscapes and for various uses. Yea, buy a few brick, cut them, do it right. Unfortunately, job is small and nothing artistic about it. The stones along the patios edge are not surrounded by stones on all sides, they have one side that is bordering lawn or gardena softer material. Take a sprinkler and wet it down , it will tighten it up , still be looser stones on top. Do you recommend using cement/sand mortar combination or to go with stone dust. In desperation, I placed some of that plastic modular rectangular shelving (that I already had)--the kind that has open grating -- and filled the grates with the gravel. If sothen fill your joints with mortar. Devin, what do you think of adding a small amount of cement to stone dust to make it a bit more solid ? didn't think far enough on this one. After that I have one side that I will change to/add retaining wall stone borders to better lock my stones in. Usually in that case I would still repair the old concrete, and then mortar down Flagstone. Sweeping sand into the joints is one way to go about it.read the article, for other suggestions , Or, check out this great article here: https://www.devineescapes.com/flagstone-what-to-use-sand-cement-or-gravel/. Great information. As mentioned in the article right above..I go with screenings. My process is described in this article: how to fill flagstone joints. In any event, it didnt get quite cleaned up enough/soon enough. Maybe a channel drain, along the wall furthest from the house? Gaps are approxly one inch. Hi Devin. Youve also referred to it as crusher dust. You can get rid of weeds easily by boiling up a pot of water in the pouring water on them. I plan on using a thicker layer of concrete sand below the stone, (up to six inches); thick enough so that it accommodates the irregular thickness, and providing me a flat stone surface on top. What is the best way to repair? First off, thank you for all your posts. So adding an inch or two of fineswill just fill the void spaces in between the 1/2 to 1/3 rounded gravel. is this a bad practice? Im just kind of not liking going with the plain gray. Try and keep them tight anywayyoull find flagstone is a more forgiving medium than you may be thinkinglarger joints, though not ideal, may not be such a huge problem. You want to go maybe 1 deep and maybe 1/2 wide. Any corrections or suggestions I should be advised of? Private commission. Devin, Thank you for the excellent article. I was planning on Breeze but hear it will be tracked into the house and wash away. Devin, Thanks for all your thoughtful advise. Do you have any ideas of what the cause could be? The larger material will help to jam up the drainage-cut, making it so less fines settle down below the concrete, while still letting water drain. Digging and tamping and rakinghard work!). These surfaces are stable. If my advice is at all helpful, then please share my stuff on social media. For example, something like this: https://www.glengery.com/mortar or maybe something from Sika? Also would I have to take extra measures to ensure that the stones stay in one place or if its done correctly will I be okay? Nope, no good. Stone dust, for the win. Thanks for your colorful commentary and your insight (with years and years of experience). I already clear out a 15 X 15 for my back patio. these fines, when dampened, actually do bind up with the larger chips, becoming semi-solid. We visited a tourist attraction that had done this. But whatever the foundation is, it shouldnt develop such a vast chasm. 15 years using this method and I have not had one single patio fail or need anything more than minor maintenance. This is a big project that you are describing.. Id recommend that you spend some time reading my other DIY flagstone articles. the concrete is cracking, stones around the edges appear to lifting. Once that was done, we cleaned off the blocks. But heres the problem: polymeric sand fails.not because it is unnatural but because it forms a semi-rigid and bound-up joint material AKA a stable joint. great article. Using your own native soils though, a person COULD screen there topsoil and collect all gravels of certain sized, and mix them with finer sand and clay particles, and thereby create a decent soil foundation, using just what you have. i am a fan of screening, but at times, find it hard on bare feet. Basic advice can be free but you worked hard and long to get those skills and knowledge. I used baking soda on my patio to kill weeds. If using sand rather than stone dust, then you should try and keep the sand depth to an inch or so. I used the granite sand as my leveling layer, too. Sure. Incorporating the gravel into the soil seems to have improved the drainage, too. Best recommendation is to use large flagstone, small joints, stone dust/decomposed granite as the leveling agent and joint material. Sure, you could do that. Push down on it, one corner of the stone at a time. Take a sprinkler and wet it down , it will tighten it up , still be looser stones on top. Sorry. Ready-mix concrete refers to concrete that is specifically manufactured for customers' construction projects, and supplied to the customer on site as a single product. In my experience a wire-brush + elbow grease will get *some* of it up, when its fresh. Yes, whenever you grind out mortar joints between flagstone, I pretty much expect a stone or two to pop up lose. https://www.envirobond.com/professional/envirosand/, https://www.landscapeandgarden.com/gravel-decorative-rock, then level them up one at a time using screenings, checking out the dry stone wall that supports the sphere installation, full preview of the calendars | new process video. * This works better with tight joints. Very useful information. He gave me samples of two kinds of much smaller type stone to mix with the pea gravel to see if that would solve it. And to account for waste and mistakes. I re-rake the kennels every few days to keep the coverage even. Thanks again! 2. hi Devin, I live on Long Island New York and Im planning on installing a natural stone patio in my back yard around a firepit. You cant really hide the edge thoughso dont bother trying to hide it, but go with an edge that you like the look of. What do you think? Pea gravel is round and tends to roll, so laying down a base layer of a more coarse, angular rock can help stabilize the pea gravel. Its 3/8 in size, and says with finesthats what you need. And dont use salt either. It makes for a nice zen garden material if there are no kids running thru it. Polymeric sand is sand with an acrylic binder added. Then I need to study how it behaves, over years. I have a slope in my backyard for about 15 to 20 degrees. Every time it rains, screening from my joints splatters into my stone and patio furniture. I thank you so very much. However, since the gravel is loose, people often need to know how to stabilize pea gravel. Also, do you have any mortar that you prefer over another? And reallymaybe make the drainage saw-cut, then fill in a couple inches with road base type gravel. Weed 2007, FWIW, I would forget the pebble idea for a dog run. I had heard it was okay but am now sorry I did not check further. Where do you buy the screenings? If an area is Shady or damp then sometimes that can cause thin algae growth that can make flagstones look dirty. Dont cover that steak in big mac sauce. Just did a repair where the sand in-between and under the flagstones was undermined by and taken over by ants. Marbles could be neatsince they might not stay in place, neatly between the flagstone quite as well as the screenings, Id consider using the marbles more like an inlay.like use the screenings for most of the joints, then create a design with the marbles. Im trying to keep my foundation dry on north side of home. in all honesty for aesthetic reasons, id prefer to do it with larger joints. I have done this, for a client. To keep the decomposed granite out of the pool, my biggest piece of advice is to take time during installation. Good luck with it, whatever you do. If you do not have any orange based cleaner, then try using a bit of vinegar along with the wire-brush. Hello Devin, We found your article a little too late. Sand was also used in between bricks as 1/8 gap fill. Hi Devin, Really helpful articles on flagstone. There are a number of cracks around a number of stones. Thanks for any advice on this. You could a) hire a professional. Ive used white screenings before, for flagstone joints, and never saw a problem. And have fun! Orange oil. Your sculptures are amazing by the way! Againdo not spray round-up or any other poison unto your patio. Would appreciate your thoughts! That doesnt mean that they certainly wont work.but as a professional, they wouldnt usually be my first pick. Thank you. Still, a leaf blower is your best tool for clearing pea gravel, since . I have an Arizona flagstone patio & sidewalk with mortar over concrete pad and live in Colorado. Also on my jobs the joints are maybe an inch wide, or less.Ive seen other hardscapes where the flagstones have 3 gaps between themtry keeping anything in there. Thanks, JoAn. Do you know if one can expect the haze to slowly fade away over time? Surrounded by retaining wallsso the patio is below grade, and a drain of some type is necessary. Im glad that you appreciate my work. I cant find anyone who sells decomposed granite. We did buy poly sand, but can exchange it for the screening. (you can always just let the weeds go.) Add in DG which will work its ways down. Can I sweep stone dust into the cracks now instead of sand? Is the patio pitched in the right direction, and pitched consistently? 3. In colder places, dig deeper and have a thicker gravel base, say 6 to 8, in warmer places 3 to 4. Does work pretty well and doesn't foam up if the stone is dusty or the ground is damp like the Gravel Lok product does. We need to replace the joints and extend the patio 10 feet. On occasions when I have wanted red for in-between the flagstones, Ive just used grey for leveling, and purchased a smaller amount of the red. So idk what to tell you..then again, over the years Ive seen a few stone patios with larger gaps, filled with stone dust, and i built a stone walkway once, with large gaps filled with gravel. Any suggestions? A bit of a philosophical question, really. Gravel-Lok - Amber Color - 50 Gallon. Then, if filled with stone dust or d/g (interchangeable, I dont know of any reason why DG might work better) the cut that you made will allow water to drain. Your email address will not be published. Problem. Youre doing a sitting wall too? I am working on installing a small flagstone walkway with decomposed granite base. We suspected that the sand had to be replace or refill/reapply, we just didnt know what was causing what we were seeing. Any idea on how to remove to get the stones back to previous state? They took the quick easy way outand left large gaps to be filled with sand. You need a foundation of compacted road base gravel. Allow the stone duts to dry and bond then come back use a non-shrinking exterior grout bewteen the flagstones..sound good?.Thanks for any input, Frank. Wait till the joint is somewhat damp, but not soaking and the fill with mortar. Flagstone, and such-like. Slugs? To lay your flagstone patio 1) set out yours tones like a puzzle, as you said. - M.K. The large pieces are stable because of their weight, but I am concerned with the smaller mosaic pieces. Do we start over? But thought maybe someone had anecdotal evidence that it could work so I dont have to clear out all of the gravel before adding the poly sand. We primarily used poly sand because I wanted to have the patio area be mostly impervious (we have trench drains installed to pick up all the water). You are so kind to answer so quickly and for the method link. We live in Ontario and I am almost done with my flagstone landing. In your case, decomposed granite joints. Pea gravel is commonly used for walkways, driveways, and as filler between stone pavers around the home. Here is a video demonstration of how i cut flagstone using a rock hammer: Be sure to comment on the video amd let me know how the technique works for you. Weed and ant proof. I have a flagstone porch with flagstone stairs. Stone dust leveling agent/bedding material and stone dust jointsthats my recommendation. Common does not mean good. I live just north of Philly (19046). Yes, it stops the joint material, sand/stone dust in place, but it hardens up, then cracks up, then you got these broken up pieces of mortar. In your opinion, should I use poly sand instead of DG or possibly just pour concrete? Ahoy, but I do see one application for this gravel glue messas a back-top alternative. Scrub with the broom a bitthen hose off. I particularly appreciate the advice on killing any weeds that get in there with hot water, vinegar or pulling them by hand vs using Round UP. Placing a border around the perimeter of pea gravel paths and walkways is one of the best ways to stabilize pea gravel. I first started seeing this stuff about fifteen years ago. I had a flagstone patio laid 2 years ago. Starting with a base layer that helps resist flooding problems helps stabilize the pea gravel by offering a firm supporting surface. Concrete is your best bet. Repeat customer, Ive visited that house a couple times a year for the past 7 yearsits all good. Great article and Q&As! Grey stone dust screenings will cost about 40-50 per cubic yard. please reply with name of screening, where to buy and if method i am thinking is good. 4. Suggestions for adding on? It is an old flagstone patio and the morter is coming out at between the stones. A leaf blower can be used to remove debris, as the stones are heavy enough that they won't blow away. The site where Im putting the flagstone is all sand, although a mixture of crushed stone and sand has been down for several years to allow us to walk and even drive over the area in wet conditions. First off, thank you for giving your location! Will this work to fill the cracks of should I attempt to find a finer material? The gaps range from 1/4 1 between stones. Worse, ants love it. And, if so, is there a way to do this so you dont see the border material for the finished project? Any suggestions on how to keep it from washing downhill? I was wondering how best to address a potential problem as winter is approaching. You can also sprinkle cement over gravel to reduce sliding and shifting. Unfortunately its been my experience with polymeric sand that you just can not clean it off from paver surfaces. remove it and install 1 1/2 size river rock. And the answer is alwaysmake them flagstones fit tighter! Im not worried about your base very much if crushed stone has already sat there for years. Life happens. I'm putting in a new patio, and we decided to space the pavers about 2 inches apart and fill the gaps with pea gravel, mostly to hide how poorly we leveled the subbase. A path made out of this material will be very loose, and will easily dispersed by foot traffic and weather. Thanks for telling me the plastic approach is lame. My brother suggested sand? Now in the above drawing, on the left is 3/4 to 1 clean gravel. The 3/8 crushed basalt is the right stuff. *If you are in a place that never gets below freezing, then these recommendations are less crucial. We probably have a dozen small ant hills to show as proof- lol. It did say that clean up was with ammonia, so isit stray cat proof? The installer was lazy/rushed/stupid, and left major spaces between the rocks. Thanks for saving me from the poly sand! Quikrete Assorted All-Purpose Gravel 50 lb. Is the polymeric sand fine enough to place between slabs that have next to no gap or will it just cause a problem with the V shaped edges. I selected Galleries and then Flagstone Walkways, the last two images once magnified to 500% show clear images of your stone screenings. We have a large concrete patio(800 sq ft?) I realize it would be better to remove everything but Im not up to doing that. Hi Devin Thanks for all your comments. If the patio is dry laid, on a sand/gravel or stone dust foundation..then theres should not be anything portland cement based in the joints. and you want to come up with a dry joint, that has the same color. Quickrete mason mix type s. Green bag. Ive seen many walkways made with only stone dust/decomposed granite. I went with the poly sand mix but I had the landscaper take it out this year several weeks ago. I used the natural dirt to lay and level and pressed the flagstone cracks with the same. I didnt provide enough info. Reddit and its partners use cookies and similar technologies to provide you with a better experience. Great article Devin, We have large slabs of Indiana ledge rock some as big as 30 sf and 4 inch thick around our pool laid with 1/4 inch tolerance laid on sand with sand between the stones sme have shift and opened gaps and tilted Its impossible to fix without big machines so I am planning just to stabilize it Screenings the best? Then tamp. Stiffin it up a bit so it's not so loose. The bricks are on now stable 1-2 dry sand beds. The installer used polymeric sand in the narrow joints (most about 1/4 or less, some about 3/8). The stone settles, the joint cracks. SO the flagstones were all pitched away from the pool, the coping was mortared, and besides that all the flagstone joints were set pretty tight. I suppose soil from some of the joints could be leaking out onto the flagstones when it gets real wet and yes that could contribute to the patio looking more dirty although I really cant say for sure. If theres a concrete foundation, then sure. I also have a pea gravel area (about 20X20') that I want to stabilize. Furthermore, the polymeric sand stays in place because it is glued together and also glued to the stones or bricks it is placed between. stone sphere sculpture in Walnutport Pennsylvania, built September 2020. Thank you for the details. Removing the grout is going to be a horrendous job. I have been struggling to find information on Breeze vs Polymeric Sand to put in the 1 grout lines. If youve already done so, I wouldnt sweat it too much. Read the directions, follow precautions (gloves, mask, glasses). There are some areas that need repair. Any idea how to remove the haze from the pavers? Ill probabvly be emailing you soon, to set up a consultation, as we have some questions about cutting, dealing with elevations and drainage issues, just some stuff particular to our project, and it would be good for someone to hold our hand walk us through the process, make us feel more confident about what we need to do. Fact is that you simply can not use polymeric sand as a replacement for taking your time and doing the job right. I dissuade all of my clients from using polymeric sand. Compacting the pea gravel will help keep it in place. Do I start with stone dust and then add a top layer of topsoil? Well, its fairly easy, but you have to becarefulthe sand is mixed with a binder. Good question. The only problem with dust is the stairs on the outside (front) edge of the stairs. I can confidently Did you set the flagstones in mortar/on top of a concrete foundation? Encourage moss to grow there. If the paver base is made up of 1/8 chips of stone, mixed up with smaller bits, much of which is so small that it is flour-like, then, well, its the right stuff. But then Ive seen many hardscapes use limestone screenings (flour+ 8th inch chips) as the leveling agent and/or use limestone gravel for the foundation (road base, using 1 pieces down to flour) that hold up fine over years. The slab is about four inches thick so concrete ran under the wood dividers and there is an irregular floor to my trenches. 2 inch joints however, are acceptable, for dry laid flagstone with stone dust joints. This, I believe, answers your need for a walkway where most of the gravel stays in place, yet is still permeable. pressure washing will definitely break screenings/decomposed granite loose from the joints. Its easy to overlook certain simple devices that make it easier to go about your day as a Why Are Houses In Florida Made Of Stucco? Luckily, there are many ways you can stabilize pea gravel on walkways and driveways. This system is somewhat self-healing. (even non-shrinking exterior grout). Good luck with your flagstone patio and fire circle then . I live in Texas with the soil is mixed clay and moves a lot. If it were me, Id repair the existing patio with mortarand then probably do the additional 10 dry laid. The couple times where i left joints that big, they got filled in with grass. Or 1/4 inch minus gravelof all the synonyms used so far in this article and in the comments, youre the first to bring up 1/4 minus gravel. Do you need hardscape help? And thank you Good luck with your flagstone project! Also, are their any loose flagstones? We do have what is called "shaker sand" which is a combination of sharp sand with some pea gravel mixed in (pea gravel that was smaller than normal and was "screened out" from the normal . Is it worth bothering with or will the gravel do the job itself? As far as separation along the cracks goesthis is a matter of technique, not of product. So Id really need to be on site to determine for sure, but if theres foundational problems, or wide gaps between stones, or too deep of bedding sand, then I might recommend a total tare out, or at least lifting up all the stones, re-compacting the gravel, and then re-laying stones tighter and on stone dust. 3. We currently carry sand that comes in 5 colors: brown, black, grey, red and buff. Its hardened as sort of a spongy material. The area is shady and I imagine the main part of the area will grow moss but the pathway off the larger area might get a little sun so maybe not there. The reason for a well compacted foundation of road base or something similar is thisroad base can be compacted and yet remains well draining. Ive never studied it, never used it for a client and been unable to study its utility over the yearswhich is a major omission on my part. Pretty much all of my DIY consultation customers complete their patios, with the final product having much wider joints than I usually allowand then, out in california its popular to build entire walkways using nothing but stone dust. Clay base, with about 4 of 1/4 clear gravel, followed by 1 of screening before putting down 20 X 20 patio slabs with next to nothing for gaps. Using decomposed granite will help the pea gravel set and not move when people walk on it. About ground cover for in between your stones.theres a few good options out there, like Irish moss (not really a moss) and thyme and others. Does lime really extend the life of the mortar joint? You can see the low spots where the water pools. Any suggestions? I never thought about the problems I would encounter using small stones on a dry-laid patio. So IDK, rip out that old drain, and install your new drain correctly. Expect to be topping off the stone dust trenches a couple times a year, first year or 2. They are basically pebbles that have both aesthetic and functional uses. You could do it either way, especially since you said these are stepping stonesfor stepping stones, i usually just use soil. It got cut off mid-sentence and Id hate to miss anything important. . I suppose that may be the same thing as mortar mix, but I'm not sure. Thank you for the prompt response. Im going to take your advice and fill the gaps with granite sand. Either fulling the joints with soil and seeding, or, during the excavtion Ill carefully remove the sodthe grass itself plus 2 of soil and roots along with it. I have never used a polymeric sand, and I am wondering if I made some out of the crushed stone I have (which is very fine, for filling the joints, and I have a lot of it still)? Yes, he was almost certainly talking about screenings. So fun, so tiring!). Thanks again for the great advice! Ive used products before where you actually add a binder to the gravel. I prefer smaller joints. Remove all the polymeric sand from in between the flagstonesget it all out of there. Just approach the work with heart and youll be alright. Seen it before and everyones gift is unique. I have in place 30 year old clay brick patios and walkways. More importantly, are you overfilling your joints? Remove excess residue with a leaf blower. When using pea gravel for a hard surface patio or similar area, you need to use a binding solution. Some joints are huge with tiny stones sort of floating in concrete. 1. Thanks! Just power washed my patio of stone pavers. If you just have sand in.and no road base gravelthen absolutely, take up the flagstone and do it all over. Scroll half-way down on this link and find the section with the heading How to install stone dust in between your flagstones Sometimes people overfill their joints to begin with, then wonder why they have material spilling out onto the patioaim to have your flagstone joints filled to about an 8th of an inch lower than the top of your flagstones. So you found out about the ants! Hi, love the blog, just stumbled into it and you have a great skill at explaining things. We dug eight inches deep, used broken concrete chunks, and then filled the voids with #411 limestone gravel, (1 1/2 inches to fines), and then #10 limestone screening on top. Is this stone in question local, or otherwise desireable to you? Before the coat is dry, apply sand over the binding solution. Screenings are not the same as polymeric sand. There is no cement now. These stones will reduce the amount of traffic on the actual pea gravel. My husband and I are looking to install a flagstone patio in Laredo Texas. It was wet out today and all the beautiful color of the flagstone was showing nicely where I have not used poly sand on the joints; but in the areas where I used poly sand it all has a dull haze and the natural colors just dont come through.