Pouring the foundation of your custom home has crucial importance, being maybe the most important part of the home-construction process. It is the base of the house, being responsible for supporting all the weight of the walls, the roof, and, of course, the people who live in it. Your architect and engineers will create specific foundation plans and calculations for your subs in the working drawings. These plans let them know where everything goes and how much dirt needs to be moved to make room for the foundation.
The engineer needs to figure out which type of foundation is appropriate for the kind of home you’ve decided to build and the characteristics of the lot on which you plan to build it. You can choose from a variety of foundation types, and every local government has different requirements. You need to discuss any variations with your contractor so that you understand what needs to be built on your property, and these decisions will likely be made with your engineer earlier during the planning stages.
Some cities and counties don’t allow any grading during the winter, so coordinating the schedule with your contractor is important. Also, weather can play a big role in delays during the foundation construction process.
Things to Do before Pouring the Foundation
Until you start pouring the foundation, you need to first dig out all the dirt from where the house will be. During the excavating stage, your lot may look like a playground filled with bulldozers, diggers, and trucks, ready to make pits, holes, and trenches.
The first thing to do is to remove the topsoil from the foundation area. Then, the sub digs holes for the footings (reinforced sections at the base of the foundation) if required. These holes will be several feet deep in cold climates so that they’re below the frost line (the maximum depth that the ground will freeze in winter). The type of foundation you install determines how much dirt to remove.
The most common variety of foundation, built on relatively flat or gently sloped soil, is the perimeter footing foundation. It’s called the perimeter footing foundation because it comprises concrete footings that go around the house’s outer perimeter. In the case of the perimeter footing
foundation, walls are built primarily on the house’s perimeter; however the engineer may have specified certain places where an interior wall needs to be built to support extra weight.
If you’re building a slab foundation, then it will be made entirely of concrete. Slab foundations are less popular for custom homes because they don’t allow for any sort of a basement, and they make the first floor feel very rigid. However, on the plus side, slab foundations are fairly cost effective compared with other options. If your house is small and relatively inexpensive, your architect may have chosen a slab foundation.
A very popular form of foundation today is the pier-and-grade beam foundation. This foundation is versatile because it requires little or no excavation. It’s often used for hillside application because it secures the house deep into bedrock, preventing potential slide and settling issues. Some contractors like to use pier-and-grade beam foundations, even on flat lots, because they can require less concrete and less excavation, resulting in lower costs.
After finishing the foundation, you need to have a clear picture of how the house will sit on the lot. Use this spot-check to be sure you’re ready to move on:
- All concrete is hard and secure, and there are relatively few cracks. No rebar is showing.
- The foundation hardware is securely in place and not bent or broken.
- Crawlspaces and utility connections have access points.
- All protruding utility pipes are clearly marked and have protective foam collars.
- All corners are square or at proper angles per the plans.
After pouring the foundation, you can finally concentrate on the shape of your future house and start the framing and the rough work.