Monday, November 24, 2014

Building An Adobe Wall: #1 Stone Foundation

This is the first post in a six part series on how to build the adobe wall that you see in the above photo.

All the posts in this series to date are:
In this post I will cover all the aspects of this wall from the stone foundation to the metal cap... well as the adobe decorations with earth and rock pigments that Allison and her sisters added.

Above you may note the burrowing owl below the Mexican Hat flowers
that are companions to the lizards, a moth, and hawks that they created.

So let's get started.

In the photo above you can see the beginnings of the stone foundation.
We use the largest stones on the bottom.

The stones are dry stacked meaning we did not use any mortar.
This helps to keep any moisture from wicking up from the ground 
and compromising the adobe wall on top.

This granite was delivered from a nearby quarry 
and of course we picked out the best stones from a much larger pile for this project.
For more on obtaining stone please refer to my post:

Looking at the photo above, 
we started with the largest stone on the right end of the longer section.
and we are still working on the left end of the wall.

This wall only goes down a couple of inches below grade.
In our high desert here the ground regularly freezes in the winter,
but our low precipitation and well drained soil means the ground does not heave 
and the nature of the wall means it is somewhat flexible to movement.

Every climate and location is different and it is important to determine 
if your wall will need a deeper foundation below grade.

A wall of this type can also be built over a french drain
 to provide drainage as a landscaping solution when necessary.
The french drain can be utilized as the foundation.

Above, we are placing smaller stones on top of the larger bottom stones
 so we can bring the top higher, level the top, 
and to bring the stone in to the same width as the adobe wall that will go on top.

The higher the stone goes the more protected the adobes will be from a hard splashing rain.
For adobe, the higher off the ground the better.

The stone doesn't need to be perfectly level,
but for this project we were shooting for keeping it within an inch or so of level over eight feet.
The mud mortar will easily make up any deviation from that range.
I find that keeping the wall close to level from the start makes it easier to get the top level.

Of course the smaller stones are much easier to keep level 
than to try and level the larger stones.

Above you may note the red crayon mark on the larger bottom stone-
 that designates the outline of the adobe.

It is best not to have the stone stick out from the adobe wall any more than you have to
 as it provides a place for rain to penetrate the bottom of the wall.

Again it is much easier to control the width of the wall with the smaller stones 
than to try to find larger stones that are the exact width.

We filled in between the stones with smaller stones from chiseling and fitting.
This is basically the "mortar" to keep the stone together and provides a base for the adobe mud mortar that will go down as we start our first course of adobe brick.

Once the adobes are set on top they will hold the stones securely in place.

The stone foundation is finished and in the next post we will get started on the adobe wall.

The posts in this series to date are:

Thanks for reading.