
Dry-stone walls
Last updated: March 10, 2009.
If you want to build yourself a house in the city, brick, steel, glass, and wood are generally the best materials to use. But what if
you're in the middle of the countryside and you want to make a simple
wall to keep animals in a field? You could use bricks, but they look
unattractive and unnatural in rural landscapes. Not only that, they can
work out really expensive when you lay them mile after mile.
And what if you change your mind about where you want the wall
to be, as farmers often do? Knocking down bricks locked together with
mortar isn't at all easy. Wouldn't it be good if there were a
simpler, cheaper kind of wall you could make? Well, there is! It's
called a dry-stone wall because, unlike a brick wall, it's
made by stacking stones without (wet) mortar to hold them together.
Dry-stone walls are strong and attractive and can last hundreds of
years. But if you decide you don't like them, you can just take them
down and build them up again somewhere else. Let's take a closer look
at how they work!
Photo: Stone walls blend naturally into the landscape. A typical dry-stone wall on the ancient Priest's Way leading from Worth Matravers to Swanage, Dorset, England. This one is made from stones quarried in the villages nearby.

What's the difference between brick walls and dry stone walls?
A brick wall is made from regular stacks of identically shaped
blocks locked together with a kind of gritty adhesive called mortar.
A dry-stone wall is much more natural: it's little more than a
vertical stack of stones laid together slowly and carefully so the
stones lock together under their own weight. Brick walls need mortar
to hold them up because they often reach high in the air (as part of
a building, for example). Dry-stone walls, on the other hand, are
used mainly for fencing in animals or marking out the edges of a
garden, so they seldom need to go higher than 1-2 meters (3.5-7
ft). By choosing the stones carefully and packing them tightly
together with very thoughtful design, you can make a really strong
structure that's completely self-supporting. Apart from looking great, it will provide
excellent shelter for livestock and habitats for rock plants
(such as mosses and lichens) and the insects they support.
Photo: Close-packed stones keep a wall together. This beautiful new stretch of wall was built in 2008, but looks no different from the ancient walls all around it.
How to build a dry-stone wall
To make a dry-stone wall, you first clear and level the ground to
prepare the foundations. Then you sort out your stones into different
sizes, typically with piles of large, medium, and small stones. Next
you mark out the area where you'll be building your wall—with taut
lines of string, by drawing chalk lines on the ground, using wooden stakes,
or in some other way. Your wall can be no wider than the longest stones you
have, so you'll need to check your pile of material to see what's
available before marking out.
Once you've marked the area for your wall, you simply pile the
stones up in flat layers. Each layer consists of tightly packed stones
with a mixture of a few large stones (called tie-stones) running lengthwise
into the wall (that is, with their longest edge
spanning the width of the wall) and lots more smaller stones
packed in between them. You need to leave as few gaps as possible, so the
stones in each layer should look almost as tightly interconnected as jigsaw
pieces when you're laying them out. Take time to choose and place
your stones carefully: dry-stone walls take a very long time to
build, if you do it properly, and it's time that's well spent.
Much like building a brick wall, you finish off a substantial part
of each horizontal layer before moving up to the next one. To keep
your wall sturdy, it's important to arrange large stones in one layer
so they bridge the gaps in the layer below, and vice-versa.
Sometimes this is referred to as building "two over one and one over two":
you need to make sure one stone covers two (or two stones cover one) in the layer below. In other
words, you have to ensure that the gaps in successive layers don't
line up or you'll create "faultlines" where your wall will be
much more likely to collapse. Another important factor also helps to ensure
stability: the lower layers of a wall are always slightly wider than the upper
ones so the wall tapers inward slightly as it rises. If your wall gets wider
as you go up, there's something wrong!
Photo: Building a dry-stone wall in Langton Matravers, Dorset. Left: Metal stakes and wooden blocks are used to mark out where the wall will go. Middle: Looking the other way, you can see how the stones are packed in. Strings run between the metal stakes to help you keep the stones straight. Right: Stones near the "construction site" have been pre-sorted into different shapes and sizes.
When you reach the height you want, you
can put more flat and heavy stones on top to finish the wall off.
Usually, wall-builders arrange flat stones on their ends along the top both to give a
wall an attractive finished appearance and to stop the top stones falling or being knocked away.
The upper stones are referred to as the capstones or topstones, "buck and doe," or "cock and hen."
Local materials and styles

Photo: Angled stones help this wall stay upright on a slightly slanting field.
One of the best things about dry-stone walls is that they're
usually built from local stones. Using materials made locally is
better for the environment (energy isn't wasted transporting heavy
building materials over long distances). It also helps places to
retain their distinctive character and charm. Dry-stone walls built
in one place may look very different from those built elsewhere,
simply because the stones are a different shape, size, or color. In
some places, the natural stones are like small cobbles and dry-stone
walls reflect this. Elsewhere, the stones may be chipped from rocks
in local quarries to make bigger and squarer pieces.
Different wallers build in different styles—sometimes to
"sign" their work and sometimes for other reasons. Walls built
up hills often use a style where the stones are packed in at angles
so their weight (leaning against the direction of the incline)
prevents the structure from collapsing. Walls designed for livestock
often have a protruding layer of stones near the top that helps to
stop sheep or deer from jumping over. In the part of Dorset, England
where I live, the wallers say they can recognize one another's style
at a glance. You can certainly see a huge variety in walling styles
as you walk around the landscape comparing one wall to another.
Something else that's very evident is the sense that dry-stone walls
are a living feature of the landscape: for one reason or
another (through ground movement, strong winds and rain, or livestock
huddling against them for shelter), walls often collapse from time to
time and have to be rebuilt. Look closely at the walls in a
particular area and you'll find places where stones that have been in
place for hundreds of years are just about to fall down; right next
to them, you'll find stones that have been built up again in the last
few days, weeks, months, or even years. It's as though the walls
themselves are alive. It's fascinating stuff! And we should count ourselves
lucky that people keep these traditional rural crafts going.
Photo: Features of dry-stone walls. Left: It's easy to leave holes for animals to pass through.
Middle: Overhanging stones near the top of a wall stop animals leaping over. Right: Walls collapse at faultlines, like this so-called "running joint." Chances are this wall will collapse the next time a sheep pushes on it too hard.
Further reading
- Building a dry-stone wall: A detailed animated guide from the Easy2DIY.com website. It's superbly clear and, with an audio commentary, very easy to follow.
- Dry Stone Walling Association of Great Britain: An organization that helps to perpetuate the ancient craft of dry-stone walling.
- Dry Stone Walling: Online version of a practical guide to dry-stone walling by Alan Brooks, Sean Adcock & Elizabeth Agate, published by British Trust for Conservation Volunteers (BTCV).