Depending on where you live in the country, basements might be the norm…or they might be more of an added bonus. I grew up in Alabama (without a basement) and never gave it much thought, until my fiance and I moved back to my home state a few months ago. We began looking around at potential homes, and he asked why basements are so uncommon here. Since he grew up in Ohio, nearly every home he had spent time in while growing up had a basement.
Although I didn’t give it much thought at first, the Nancy Drew in me was curious so I did some digging (no pun intended!) It turns out the reasoning for this is more climate driven than culture driven. Basements can be built in the south, but it’s typically a greater hassle and more expensive than it is for our friends to the north. But why?
It turns out there are multiple reasons, but the first culprit is damp soil. Many southern states have a lot of swamps or wetland territory, combined with significant lengths of coastline. There is simply too much water in the ground to make most basements feasible. And when the water table is less than a meter or underground (hello, Florida!), building an 8 feet or greater basement is not possible. Even in drier climates, the composition of the soil can make basements impractical or even dangerous.
The second reason is due to the frost line. The American Meteorological Society defines the frost line as the maximum depth of frozen ground during the winter. It varies with the nature of soil and the protection afforded by vegetal ground cover and snow cover, as well as with the amount of seasonal cooling. Much of the south has a frost line that’s 6 inches or less, while that number grows quickly the farther north you travel.
Building codes require that foundations be built below the frost line in order to avoid freezing and cracking in pipes. In colder regions, the frost line is deeper below the surface, so the cost of installing a full or partial basement is minimal (comparatively) since the foundation already has to be built deeper to begin with.
There are, of course, always exceptions to the rule. Basements can (and are!) be built in the south, and there are different precautionary measures one can take if they want to build a house here. It is certainly more uncommon – but not impossible!