Installing a Drystack Stone Wall

“We can throw stones, complain about them, stumble on them, climb over them, or build with them.”

William Aurthor Ward

The funny thing about this quote was as a novice stone wall installer, I’m pretty sure all of the above happened during the course of the project. I am no expert in a lot of general trades. The “Jack of all Trades Master of None” definitely fits the bill on my abilities. There is something to be said about the pride there is in doing a job on your own, although as I am getting older I sure do appreciate times where you can write a check and have the job done. My problem tends to be I often feel a little guilty having someone do a project I know I can do. I don’t know why, but I do like doing the work. So far this spring one benefit of being locked down at home is we are getting a ton of work done around the yard. One of my negatives of doing my own work is the tendency to jump from project to project… maybe at about 75 percent completion. So far this year that hasn’t been the case; I’m checking off Nikki’s to-do list with completed projects at a great clip!

I’ve often realized there’s not a lot of great information for the average person on installing a dry set stone retaining wall. One thing people often will ask is if they can do a mortared wall for retaining soil. You can, but there are a few caveats to this. One, if you live in an area with a strong freeze and thawing, you need to do a lot more base work like pouring a slab. If you live in a warm climate it’s no problem.

I did a drystack wall because it will hold up forever in our climate when installed correctly. It can feel like a bit of a daunting task, but not one that is insurmountable. One of the big tasks is figuring out what you will all need for materials. A repulatable stone yard should be able to help you with the basic products needed. The big things to know is how many square feet (face of the wall) do you need, what type of soil you have where the wall is going (sandy, clay, subsoil, etc.), and how high the wall is. These three things can get you started with estimating your project needs.

Remember, there is no shame in hiring a professional landscaper for a project like this. If you are concerned or just not sure it is a project you can tackle, that’s ok. This one isn’t for every DYI’er. If you are doing it yourself, spend the money on tools and rentals to make the project easier. I admit, I am very lucky to have access to tools and equipment to help.

There are a couple of items that aren’t always recommended or included in a wall design, but I feel for the low cost are good to include. A few key products are 4″ drain tile for behind the wall, landscape fabric for between the clear stone and soil, a 3/4″ clear chip – do not use rounded stone as it does not interlock the way clear chip does, and a landscape adhesive to glue the top row. To me, they are cheap investments and will make for a better functioning wall.

There are two items that you can’t skimp on – the stone (obviously) and the base. For the base you should use a crushed stone. Some people like to use screenings which are very small, some will recommend a 3/4″ dense (minus, road gravel, etc…). The biggest thing is to make sure and add a base.

Now that you have the stone, it’s time to get moving! Base of the wall is critical, and in my opinion the most work. Nikki and the kids did a great job shoveling the base while I installed stone steps.

The base should be dug out at least twice as wide as the width of the stone. So in my case, the stone was cut to 12″ wide making the base 24″ wide. The depth and amount of base material has a lot to do with the type of soil and size of the wall. When retaining walls get tall, or the soil isn’t ideal (like clay or sand), you may need to have an engineer assist with best practices. I know it doesn’t sound ideal, but a retaining wall is something you only want to do once.

When adding gravel for the base you should do it in “lifts” or layers. The best way is to add two inches at a time. Put down two inches, and run a plate compactor over the gravel several times till you can’t press in. Do this till you get to your desired base thickness. You will also need to bury some of the stone. I usually will bury about 2″ per foot of total wall height. I don’t know if that’s good science, but has worked well for for me.

Clear gravel was placed around the pool when it was installed. In one of the earlier photos showed where a 4″ drain tile was installed. The tile drains into a sump tank to handle the rush of water. It is key to get water away from the wall as water will do damage over time, especially when it starts to freeze. Now that the base is installed and the drain tile is ready, you can start installing the stone wall.

At this point – you keep going, stone by stone. A grinder with a diamond cup head does help if there are larger knobs on the stone. You can also use your hammer and chisel to chip them off. A couple of things that I find important to do when installing a wall:

• Keep vertical joints from being directly over each other. This can be difficult to avoid, and is ok from time to time. Just know the wall is not as strong if you have a long vertical joint.
• It’s recommended to have at least 4 inches between vertical joints.
• You may need to cut some of the stone to make a radius. The best looking walls have minimal “windows” where there is a gap between the the stones on a row.
• As you go up a row set it back about a 1/4″ or so each time. If you build the wall completely straight/plumb there is a pretty good chance over time it will tip out and fall over.

We were lucky. The weather was amazing and we were able to get the project done in a pretty short amount of time. This is about the Tenth wall Nikki and I have worked on throughout our almost 30 years together. We’ve become a lot more tolerant of each other, and I dare might even say we had a pretty good time doing this project.

Next up on the list? Well, the list is not getting smaller. We do have a couple of pretty exciting projects we want to do this summer, so check back later to see what we accomplished this year!