Your home’s foundation is one of the main structural components you may have concerns about when making your purchase. While it’s easy to see a roof while touring a property and most buyers will look up, it is important to look down to see what type of foundation is present as well as the condition and age and with a licensed inspector, try and identify any potential issues. Each foundation type will have pros and cons and it will be helpful as a buyer to know what to be looking for while touring. Let’s look at some of the most common types of foundation you will see in The Valley.
Basement Foundation While very rare in The Valley, you will see basements from time to time. The main reason you do not see many basement foundations is because of our climate as well as our soil. About a foot down you will find Caliche, thank you Geology degree, a type of natural concrete made of calcium carbonate, rocks, and gravel. This tough material is expensive and time consuming to dig or cut through, which is why you don’t see many basements. The advantage is that a basement will provide additional living or storage space, the downside is you will have additional maintenance, potential water issues, potential for radon gas increases, and these are the most expensive to install, therefore will increase the cost or price of the home.
Crawl Space Found mostly in older homes, they consist of footings and a poured concrete or brick stem wall. To the concrete stem wall the floor joists or other type of flooring is attached to create your internal flooring. This floor will be a few feet off the ground and give you an unheated and uncooled but ventilated ‘crawl space’ for storage or easy access to plumbing and electrical components. Crawl spaces were attractive because they required less digging, less expensive to install, and provides easy access to utilities if future repair or replacement are needed to the pipes or wiring. The negative, no one wants to go down there!
Concrete Slab The most used foundation you will see while touring homes in the valley is a concrete slab. Since we do not experience a freeze and thaw cycle, we do not need to worry about the soil shifting or the slab cracking during these repeated cycles. Slab is also the least expensive type of foundation you can install when building a home. The solid slab is also ideal for keeping insects and other pests out of the home. Older homes will have a basic slab of concrete but on many new builds you may see a post tension slab. These slabs are poured with steel rods running throughout and have a large amount of tension added to provide additional strength as well helping to preventing cracking. Most people like concrete slab for it’s cooling feel as well as no creaks and squeaks, however, the issue is the sewer lines running in your slab- when it’s time to replace, you may be saw cutting your floors!
When purchasing your home, you will want to look at the edge of the slab or stem wall around the base of the structure to find evidence of spalling and poor drainage. If caught early, it is inexpensive, easy to patch, seal, and paint to stop and prevent the spalling from continuing to compromise the slab or stem wall. Adjusting the slope of the soil away from the structure will also help keep your new repairs intact. The reason it is so important to maintain the foundation of a slab or stem wall with poured concrete is that they are almost always built with rebar that is made of steel. If the water that is causing the slab to spall or deteriorate reaches the rebar, it will cause it to rust and expand. This is bad because the steel rebar will expand up to 4 times its original size and begin to break up your concrete slab or stem wall.
If the home you selected has visible signs of foundation spalling or other issues, work with your agent to create an inspection plan and possible referrals for any specific repairs during the Inspection phase or once you own your new home.
Written by: Colby Schmeckpeper