Updated: Aug 27
Some might say that the foundation is the most important part of a home -- it is what everything else rests on, after all! When it comes to a home's foundation, there is much to know, learn, and watch out for in terms of cracks/problems, different types of foundations, and red flags indicating that it's time to call a foundation specialist. Keep reading for pertinent information that will allow you and your home to rest easy for years to come.
As the name suggests, a concrete slab is a block of concrete (usually 4" - 8" thick) upon which a home is built. Inside the slab are steel rods for reinforcement and drainage pipes for water. Slab foundations are very popular today, likely because they are extremely cost effective and easy to build or install. Another advantage is that there is no gap between this foundation and its house, so termites and mold are unlikely to cause a problem. On the flip side, though, this lack of ventilation can cause warming in the house. Perhaps the biggest drawback of a slab, however, is that it lies low to the ground and can leave a house susceptible to moisture and flooding issues if there is a lot of precipitation.
A basement foundation is simply a perimeter of concrete pillars (usually dug at least 8' underground) that supports the structure of a home. Basements are popular for obvious reasons -- they create an additional layer of living and/or storage space. A huge advantage of basements is that they provide ventilation under a house; a house with a basement is likely to run cooler than one on a concrete slab. Homeowners tend to appreciate this feature in the scorching Summer months! One disadvantage here is that basements are expensive to build. Additionally, they do require maintenance and can lead to moisture, mold, and flooding issues in a home if not properly built and maintained.
Builders tend to use crawl space foundations when they are building on dense soil that is a challenge to dig or move. A crawl space is essentially like a mini basement (sitting 3' or 4' underground rather than 8' or more in the case of a basement). Like a basement foundation, it contains a perimeter of concrete blocks that supports the structure of the home. Aside from the additional living space, crawl spaces have many of the same advantages of basements. They provide a great barrier against water and loose soil, and like basements they provide great ventilation and cooling capabilities for a home. It is imperative that crawl spaces are properly insulated and sealed, because if not, water can become trapped beneath a house and create moisture and mold problems for homeowners.
Potential Foundation Problems:
Foundation cracks are common, and all houses have at least a few that occur as the concrete shrinks and settles during the building process. Hairline cracks that show up at the mortar between concrete blocks are generally not serious. The same is true for cracks that occur in an L-shaped section of a foundation (i.e., as a foundation steps down to follow a hillside). These typically show up as the concrete shrinks when curing and do not represent a structural problem. More serious cracks are those that occur in masonry joints as well as all horizontal cracks. In both cases, it is best to hire a foundation expert to take a closer look and to determine whether or not a new foundation is in order.
Unfortunately, cracks aren't the only foundation problems that can occur throughout
the life of your home. Others, such as foundation settlement, deterioration of stem walls, and foundation heave, can also wreak havoc on the structure of your home. Signs that might indicate a foundation issue are visible cracks on the inside of your home -- specifically on walls, floors, and window openings -- as well as doors and windows that stick upon opening or closing. Other red flags are basement walls that bow inward, chimneys that lean in one direction, sagging ceilings or floors, sinking front porches, and water or moisture damage of any kind. If you notice any of these potential issues when performing your regular home maintenance routine, it's wise to contact a foundation professional at once. When it comes to foundation woes, the phrase "pay now or pay later" best sums it up!