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Our Construction Designs:
At Stoneleigh Masonry Designs, we start out with concrete reinforced with steel rebar foundations. We allow to cure for 24 hours, then start
construction of the mortar and stone.
Traditional Dry-Stack Stone Walls:
Stone masonry originated with dry-stacked stonework where the walls are carefully layed up without mortar. Gravity
serves as the glue that holds everything together. Free-standing dry-stack stone walls are usually made larger at the base and then taper
in slowly as the height increases. For absolutely no expense but the labor, farmers built miles upon miles of stone fences this way in
Ireland and in the northeastern states.
Traditional Mortared Stone Walls:
Mortared stone walls evolved out of dry-stack stone work with the emergence of cement mortars. The first cements were
made of burnt gypsum or lime mixed with water to make a paste with slight bonding capability. Stone walls still had to be built as carefully
as they were without mortar. The cement paste just filled the gaps between the stones and cured to form a soft, rock-like substance.
The basic formula for modern cement originated in England in 1824. It is called "Portland cement" because the color is similar to the rocks
on the English island of Portland. It is still called Portland cement everywhere in the world it is manufactured. This cement is made with
calcium from limestone or chalk, plus alumina and silica from clay and shale. The ingredients are ground, mixed in the right porportions and
burnt in a kiln at a temperature of about 2500 degrees F (1350ĒC) to drive out water bound up in the raw materials. In the kiln it fuses into
chunks called clinker. It is cooled and powdered, and gypsum is added to control how fast it sets up. Portland cement is mixed with sand and
water, and often lime to make a smooth mortar for stone and brick work. Adding the lime makes the mortar softer and more flexible.
With the aid of Portland cement it is possible to build a taller stone wall that does not taper inward like a dry-stacked wall. The cement
has some ability to "glue" a stone wall together with less care, but proper stoneworking techiques are still important. Building a
free-standing stone wall is a true art and requires a lot of time and skill to do it well. For more details on traditional mortared
stone walls, be sure to check out Building with Stone.
Veneered Stone Walls:
Most stonework today consists of a non-structural veneer of stone against a structural wall of concrete or cinderblock.
Concrete consists of Portland cement mixed with sand, gravel and water. The larger particles of gravel interlock like little fingers to make
the concrete resistant to cracking. Steel reinforcing bar can be added to serve as much longer "fingers" to make a wall that is very resistant
to cracking. Concrete is a fast and relatively inexpensive way to put up a structural wall, so few people take the time for labor intensive
traditional mortared stone walls any more.
Instead, the structural wall is put up first, and thin, flat stones are essentially glued onto the face of the wall with cement mortar. Metal
tabs in the structural wall are mortared in between the stones to tie everything together, otherwise the stonework would just peel right off
the wall. The structural wall serves as a form on one side of the wall to make it really easy to lay up the stonework, provided the rocks have
good flat edges to work with.
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