Expert: Daniel Humphrey - 2/8/2009

Question
I live in the high desert in southern california where it is very dry, I would like to know if I can build a home using concrete blocks?, I also like to know if I can fill the inside of the blocks with just concrete, of course leaving room to rukn pipes and wiring.

Answer
Dear Lee,

The high desert is a great environment for block construction. I was born and raised in that environment. One of the great things for construction there is that you don't need to worry about condensation problems inside the wall. But conventional block houses are cold in the winter and require additional heat; whereas a house with better insulation may not need any heat other than the sun that comes in from a deliberate passive solar design.

Cinder blocks are the best kind of concrete blocks for their light weight and insulative properties. They are also easy to carve with a masonry hammer and diamond saw to accommodate pipes and wiring. Unlike wooden walls, block walls can be easily curved or shaped into domes. Cinder blocks also are made with a cut-stone surface if you want to keep that look and don't want to apply stucco.

Although you can build with just a single layer of blocks, a better method for an outside wall is the double wall, where a void is created for insulation, plumbing, and wiring. Both inner and outer walls can be block; or the inner one can be stud framed. Normally, a block house is best served with a crawl space, for running electrical, plumbing, and other mechanical. But if you have a stud framed interior wall, you can use it to run those things and save a lot of time on the masonry work, and also do it on a slab.

I use cinder blocks as an outside veneer, or dado, thickening the wall up to about the four-foot level. You will see this design feature in New Mexico and Arizona in the older houses, but the dado is formed of adobe. The masonry wall in a rural environment is superior because rodents can't get in, and it is impervious to rain and sun.

Block walls are sometimes filled with concrete and rebar. In fact, some cinder blocks are made to lock together without mortar and are joined by pouring concrete inside the voids.

There are lots of books on building with blocks. I'm sure your ideas will keep evolving as you study up. There is a lot on the internet. Sometimes a fun place to start your research is by visiting a local cinder block company.

Good Luck,

Daniel