building with dry-laid natural stone

chilton limestone walk-front yard.

I love things made from natural stone.  There's really no substitute for it and no short cuts to take when building with it.  It's a masochist's medium.  Even building something relatively small with with stone leaves you with a backache and bloody hands.  But it's worth it.


To me it feels like dry-laid natural stone is to hardscape what permaculture is to softscape, or the planted world.  It's a human intervention in the landscape, but one that uses a product of nature, with minimal fabrication.  And the material is re-usable if the maker decides to unmake and create another thing with the same material.  Working with natural stone also pretty much guarantees you won't be using machines since cutting it isn't really practical, at least not often, and the uniqueness of each piece makes placing it with machinery difficult.   So you're doing a lot of lifting, then looking, contemplating, and re-lifting.  It's exhausting and also a little bit zen.



If you want to have stone in your yard and you don't want the backache, you'll have to pay a mint to get it.  But that's because you're paying for someone else's backache, and for the diesel to get it to your yard.  Stone itself isn't expensive.  I was able to buy a big pile of secondhand stone from an architect who had listed it on craigslist for $500, and who had sat on it for weeks.  I offered him $200 and he took the offer without hesitating. I left wondering if he might have given it to me free if I asked.

front yard stone pillar/pilaster

But where I paid for it was in moving the stone.  It was piled up into a neat pile in his driveway- about the equivalent of 6 or 8 pallets of stone- which would equal about 12 to 16 tons of material.  I rented a pickup and called a friend to help move it.  I thought we could take it all in a day, but we were lucky to bring 2/3 of it home.

not the right way to lay stone- running joint

The truck looked ready to blow a tire each time we loaded it, and in retrospect, I shouldn't have put as much in it as I did.  In later projects, I've rented a moving van, which happens to have a  much higher load capacity and doesn't cost much more.

My back was ready to blow the next day.  And we hadn't even gotten all of the stone.

the right way- lapped joints, even at the corners

Of course, now that the work is done, I love the stuff.  I was able to build  a window well out of it, use some for my stone walk, and the rest went into the stone walls around the patio and garden.  It looks as if it has been there for decades, which is the look I was going for.  Stone seems to make itself at home pretty quickly wherever you put it.

I've been able to work in some volunteer stone and concrete I've found while tilling the yard, and I've had to buy some stone to fill in spaces where a neater cut was necessary, like the pillars in the front yard, but over half of the stone is salvaged, maybe two thirds of it.

Limestone is my preferred medium, since it's abundant here (which also makes it relatively cheap) and easy to work with.   There are some tricks to building with it though.

1. The base is important- spend the time to lay a good crushed rock base

It's easy to get excited about laying a stone wall or building a pillar, but laying the base is boring.  Digging a trench takes a long time- you usually hit roots, and it always seems to be shallower than it's actually supposed to be.  And trenches swallow up aggregate, which gets old pretty fast.  The aggregate also has to be crushed rock, not river rock or any other types of weathered, rounded rock.  The reason is simple- crushed rock is angular and tends to lock together with other angular  pieces, while rounded rock  acts like a ball bearing, causing things above it to roll when pushed.  There will be a lot of pressure exerted on your wall over the years, from water and soil and people walking on top of it.  You do not want to have the equivalent of ball bearings underlaying it.

Make a trench as deep as the average depth of one piece of stone, plus about two inches.  That is, if you are using stones 6" tall on average, make the trench 8" deep.  Fill it with six inches of aggregate, and pack the aggregate down with your boots, or with a tamper if you have one.  When you're done with that, have a beer.

2. Give water a path out of your wall 

deteriorating mortared block wall, camouflaged with bricks

This is something that usually isn't a problem in dry-laid stone construction, but something that most people who haven't built walls don't think about. Dry-laid stone walls are naturally full of gaps for water to pass through.  Mortared walls are relatively impervious.

The wall to the left was built in the 1940's or 50's and built of concrete blocks mortared together.  There is a downspout from our neighbors' roof that outlets just behind the wall, and water percolates through, dissolving the blocks and mortar in the process.  Re-pointing the wall would be pointless, as the wall would then act as a dam, and water would again find a way to force its way through, or topple the wall altogether.

Even with a dry-laid wall, there are times that it may make sense to put a drainage system behind the wall.  Clay soil is a good reason.  We have sand, but just to be safe, and because I don't want to have to work on the project again, I've placed a 4" perforated plastic drainpipe behind the walls I've built that outlet to the raingarden.

3. The first layer of stones is the most important

Making the first layer level makes all the layers above much easier to lay. This is really important when working with stones that are all different.  The first layer is easier in some respects, because the aggregate layer in the trench can be dug into or added to (within reason) in order to make the tops of the stones level. 

4. One stone on two, two stones on one 

The mason's mantra- one on two, two on one- applies even more so with dry-laid stone.  The weight of the stones and the friction between the stones is what will keep the wall vertical, and stacking stones in an overlapping fashion adds a great deal of integrity to the wall.  I haven't always followed it, but try to keep running joints from being more than two blocks deep.   It's difficult, but even more beneficial if you can lap stones at corners as well.

5. Make the top layer of the nicest stone, and level

The top layer of stone will be what is most visible, and will be laid after many previous rows of uneven stone are laid.  If you have store-bought stone, this is the layer to use it on.  Shim it if necessary.

6. Don't be a perfectionist- stone settles

I don't think a true perfectionist would be able to take on the building of a wall with something as uneven as natural stone.  You will have to live with some level of imperfection- and as the builder will see it every time you look at the wall.

And- stone does settle- as does every other material you could make a wall out of.  It does, however, look a lot better after settling than does modular block or poured concrete.  Even the most perfectly laid wall will probably be a degree or two out of level after 5 or 10 years.

7. Buy some leather gloves and a torpedo level and actually use them

I don't always wear gloves when I build with stone, and when I don't wear them, I end up with rough and usually bloody hands.  This year I finally bought a good pair of well-fitting leather gloves and wore them.  That made work a lot nicer.  There are lots of guys who don't do this sort of work often who consider themselves too macho to wear gloves when landscaping.  I've seen stonework change this sort of guys' mind about that more than once.

A torpedo level won't save your hands, but it may save your sanity.  It's a small level, a foot long or less, that's tapered at the edges, and for a lot of reasons is much more useful and practical than a carpenters' level.  Spend the ten bucks on a torpedo level and be happy.

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It's true that dry-laid stone is a masochist's medium, but a satisfying one still.  Feel free to comment or email with questions if I haven't dissuaded you from trying to build with it.   Just don't ask me about mortared walls.  Thanks.