For the past 20 years I have been building stone walls in the greater Seattle area. Here are some of them along with some info about the main variations available: Dry Stone, Masonry and Rockery.
The image to the right shows a somewhat unusual scenario where the design called for building two walled-in planters that also served as retaining walls for the entrance to the raised house.
Because we wanted to maximize the room for planting soil inside the structure, this was a rare combination of stacked ledge-stone that was given a slip-form concrete backing. So though it appears Dry Stone, it actually is a masonry structure.
Dry Stone
(aka Dry-stack)
Just like in the days of old, walls are still made without the use of concrete or mortar (hence the word "dry") And when made with care these walls are not only gorgeous to look at, but have many benefits, not the least of which is that they withstand the inevitable slow movement of the ground over decades.
Though we aren't blessed with the fine stone walling traditions of Great Britain and other parts of Europe, here in the Northwest US we hold our own with some real quality Dry Stone Walling. Often imitated with phony manufactured siding, well-built Drystone walls form an ornate tapestry which is attractive to the eye and therefore is perfect for making a visual focal point in any landscape.
Stone Masonry
Stones can also of course be combined with poured concrete and/or cinderblock CMU to make a Masonry Wall. This is more commonly seen in more modern and upscale applications and in civic spaces. The steps needed for this work are much more involved, requiring first the pouring of a footing slab, then the vertical core. Special considerations must be made for drainage because of its impermeability.
Walls like this are more often than not capped off using 2" stone slab material. The joints between the stones are kept to a consistent width, normally a 1/2", and then tuck-pointed with mortar.
Rockery
Lastly and most-affordably, "Rockery" is what we call structures built out of rough chunks of rubble, ie. boulders of varying sizes. There are a great deal of rockery retaining walls around the Seattle area because the material costs next to nothing and large walls can be constructed using an excavating machine. So a lot of houses built since the 1800's were given a raised yard, either to retain a hillside or to help create a below-ground basement without having to dig too deeply.
But rockery can also be made on a much smaller scale, using pieces that are proportional to the job at hand. The stone yards which carry this material normally keep it binned according to size so that it can be easily scooped up with a front-loader (or a rock claw). The wall shown was done with pieces of basalt that were anywhere from 25 lbs. to 300 lbs. And in this case a lot of extra time was spent fitting the stones more tightly than usual and with as flat of a surface on top as possible. (This kind of rubble is as hard to shape as it is inexpensive to purchase.)
Which kind of stone wall fits your landscape design? Call us up email for a free consultation and estimate - I can help you find the perfect choice in regards to materials, budget and functionality.
Take a look at our Walls & Steps gallery on the website.
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