Does a House Have to Have a Basement in Minnesota?
I’ve been asked this question so many times I knew it warranted a blog post. The short answer is no. While almost all houses in our state DO have basements, it is not a law, nor code requirement. In fact, many 2016 homes built in Woodbury do not have basements.
Many homes around the country DO NOT have basements
Homes built in climates in the South which are below the frost line typically do not have basements. Many homes in south Florida are built in areas where the water line is a few feet below grade. It doesn’t make sense to have a basement there because it will most likely flood. California saw a housing boom in the 1800s. Root cellars for food storage were common, but basements were not. According to the LA Times, basementless homes were a building trend that continued throughout the Golden State. Constructing a home without a basement is cheaper and takes less time. It also lends itself to pre-fab or manufactured home building. A building built without a basement is known as “slab-on-grade.”
How to build a home without a basement in Minnesota
A home without a basement, as noted, is a “slab on grade” construction. In Minnesota we put footings in below the frost line (3-4 feet down) and insulate the slab (a poured concrete “floor” ) with rigid insulation (similar to styrofoam). You will need to insulate both below and at least 4 feet out from the edges of the slab. Footings are usually made from poured concrete, in some cases you can use pressure-treated wood for the foundation but this might only last 25-30 years. In areas farther north, such as Canada, the frost line can go down 4-6 feet so the footings will need to be even deeper.
Why do you need to insulate a slab-on-grade?
Insulation is used prevent the ground from freezing. Freezing, oddly enough, expands water. So, when the ground below the slab freezes it can crack the slab. Deep footings and proper insulation prevent freezing, expansion and other issues. If you want to know what happens when you don’t insulate a slab, just check out our roads in April or May. After water gets into a crack or small hole and freezes, it expands and contracts and causes huge pot holes, splits and utter road decay.
Why should you have a basement?
In Minnesota, no matter what type of home you are building, you must put footings down 3-4 feet below the ground. If you are going to do that it usually makes sense to dig down another 4 feet to create a basement. Basements are great spaces for:
- Livingrooms, TV rooms, or a pool table/ recreation room, office or guest room
- Mechanical equipment; Your furnace, water heater, fuse box
- Storage; A place for your fake Christmas tree, Halloween decorations and high school memorabilia
- Utility: A place to wash, iron and mend laundry, do a craft, have tools and a workbench or exercise equipment
If you do not have a basement, you will have to create space on the main floor for these things.
Basements are not necessary
A basement doesn’t do much for holding heat, making a home more energy efficient or green. But we are used to having basements in the Northstar State. We tend to feel safer knowing there is a place to go in case of severe weather. When that twister came through Kansas, Dorothy knew she and Toto had to get to the root cellar. And she was spot on: It’s a fact that a home with a deep basement with a poured foundation usually means a stronger construction overall.
So, should you have a basement? There are pros and cons. I offer a free one-hour consultation to potential clients to discuss issues such as this.