A main advantage of a concrete slab foundation is its low cost. The materials involved are not expensive and little excavation is necessary. The project does not require foundation walls or footing either, so the process can go very quickly. As a result, you can keep labor costs down as well, making a concrete slab foundation one of the most budget-friendly options when building a house.
Because a concrete slab foundation does not require major excavation, installation is extremely quick. The timetable is actually much faster than most other types of foundation and the foundation and first floor are actually completed at the same time. In fact, builders can start framing walls the day after they pour the concrete for the slab. As a result, your home can be completed more quickly with a concrete slab foundation than with other foundation type.
A concrete slab foundation is usually only suitable in mild climates where the frost line is not very deep. If it is used in an area where the ground freezes at deeper levels, ice that forms below the top layer of the soil can start to grow vertically and press against the concrete foundation. It is actually strong enough to crack the concrete or shift the foundation slab.
As a result, severe damage may result in your home's foundation. You must take special frost protection measures in a colder climate, which can often offset the savings that come with a concrete slab foundation.
In many cases, water supply and drainage lines, as well as heating and cooling (HVAC) ductwork, go beneath a concrete slab foundation. If damage occurs to any of these lines, repairs can be quite costly since it is extremely difficult to access them. In addition, HVAC ductwork may collect moisture from beneath the concrete during wet weather, which may cause mold to grow inside the ducts.
As a result, there is risk that spores may be blown into your home when you use your air conditioner or heating system. In colder climates, the concrete slab foundation may affect the efficiency of your HVAC system because the concrete may conduct cold from the soil into the house, if you don't take measures to stop it.
When your home has a concrete slab foundation, it is extremely difficult to make additions or changes. They can often look uneven and mismatched compared to other portions of the home. If you believe that you may need to modify the design of your home in the future, a concrete slab foundation may not be your best option.