What Is The Best Foundation For My Home?
It’s hard to say exactly which foundation is best, a concrete block or poured concrete though most builders choose poured walls for new homes. According to a survey by the Portland Cement Association, 72% of new homes with full basements are built with poured concrete wall systems while concrete block walls hold 25% of the national market. Each type has its pros and cons.
Types Of Foundations
A slab is one of the most common types of foundations, requiring the least amount of lot prep to begin building.
Installation is simple compared to other foundation-types, making slab foundations popular among homeowners for their relatively low price tag.
Like all foundations, the slab starts with concrete footers poured 24 inches below projected finish grade. After the footers are poured, a minimum of two layers of concrete block are laid on top of the footers. After the blocks are laid all internal piping is installed. Then a rock filler is added, followed by four inches of concrete poured on top.
Let’s get into specifics —-
Concrete Block Foundations
Prior to the 1970s, concrete block foundations were the most common type of foundation as nearly every house was built with a concrete block foundation. Concrete block walls carry a high compression strength meaning it can hold more weight on top of the foundation. For this reason, engineers choose concrete block wall foundations. Another benefit to a concrete block wall is that the concrete is already solid at time of construction meaning the wall is solid from the start.
The drawbacks to a concrete block foundation are several. First of all, skilled bricklayers are required to install a good block wall which means more labor costs. Furthermore, bowing of concrete block walls is a consideration as they are prone to buckling and bowing which can involve costly repairs.
Water and weather wears down the mortar that holds the concrete blocks in place and over time, this causes leaks. Concrete block walls that have bowed or are leaking can be repaired by a professional waterproofing contractor. It’s highly recommended that concrete block foundations are waterproofed to prevent water in the basement.
Poured Concrete Foundations
Poured walls tend to be the preferred choice of new construction at this time.
Poured concrete foundations have a better lateral strength meaning they are able to resist more pressure from the water and the soil from the outside. These walls can also be formed in any foundation design. Because these walls don’t have the same joints filled with mortar as concrete block walls do, poured concrete foundations are easier to waterproof providing some savings.
Yet there are a few drawbacks. While it is faster and more efficient to construct a poured wall it can be expensive if the cement plant is far away. If the concrete truck has to travel more than 90 minutes, a concrete block wall foundation is likely the better choice. Also, since poured walls need to cure once poured, they can lose some strength in the process if spilling occurs.
No matter which type of foundation you currently have in your home or choose for a new home, install a proper waterproofing system to prevent leaks in your basement.