The Foundation

In Houston, we always had slab foundations, but in HSV, most houses are built on the sides of hills, so they have pier-and-truss (or pier-and-beam) foundations. I would guess that fewer than 10% of houses in HSV are built on slabs.

After the surveyor has laid out the boundaries of the lot and the construction area has been cleared of trees and brush and leveled, the next step is to pour the concrete footers. These are holes and trenches which are dug and filled with concrete to provide support for the slab or piers and foundation walls.

Before digging the holes and trenches, the floor plan is laid out on the ground with paint or chalk so that the workers know where to dig. If a plan is very basic, such as just a rectangle, this step may not be needed.

After the footings have cured, which takes 3-7 days, foundation walls of cement blocks are normally erected.

See this article at for information about using a form to pour the footing and beam in one shot and saving the 3-day wait for the footing to cure. The forms are available from

ThisOldHouse also recommends pouring concrete foundation walls instead of using cement blocks.

If your garage is on a slope, the choices are to put up the foundation walls for the garage and fill them in with dirt and pour the slab on top of that, or put in a suspended slab. The former method is probably cheaper and easier, and that is what was done at our house. At Judy's house, her back patio is 4' off the ground, and we also used a slab on cinder-block foundation filled in with dirt.

The fill-in dirt must be thoroughly compacted; otherwise, it will settle over time and your slab will settle with it.

On mountain-view lots built on extreme slopes, the builder may have no choice but to use a suspended slab. Either way, if you work on your car a lot, you might want to have the builder leave a hole in the floor where you can stand up under the car to work on it.

The final part of the foundation is putting the floor trusses across the piers and putting subflooring (plywood) on top of that. A cheaper (and weaker) alternative to trusses is to use 2"x12" wooden beams. Craft uses trusses. (The vertical studs seen in this picture are not part of the support system. They are framing for the wall of the storage room.)

Most builders cover the vapor barrier with gravel to protect the barrier from getting torn up by workers walking on it. (The rental house we lived in for 8 months, built by Cooper, did not have the gravel.)

Batt insulation is put between the trusses. As you can see in the picture, the advantage of crawl space instead of a slab is that you can easily (depending on the slope of the lot) work on plumbing and electrical lines.

When the subflooring was put down, we were able to walk across the floor and for the first time see what views we would have from all parts of the house. Since the lot slopes, the floor is as much as 10'-20' off the ground. Unless you climb a tree, you can't see the views your house will have until the subflooring is in place.