Should You Install Hardwood Floors in the Basement?
Hardwood Floors and Basement Guide
So you have a carpeted basement and want to take the step to rip that sucker out and install some hardwood floors down there. Can you actually do it and if you do, is installing wood flooring a good choice? The answer is yes and no. Usually, the reason why people would want to lay wood floors in the basement is to match the rest of their house. The northern part of the US is a prime example; Most homes in the New England area have red oak strip floors in the main living area on the first floor.
If this rings a bell for you, understand that generally speaking, installing a solid 3/4" hardwood below grade (ie. your basement) is not a good idea because of potential problems with moisture. The moisture can come from a variety of places such as rainwater that seeps in from the home's foundation and if you are installing solid hardwood, you can expect cupping or crowning to occur. And when this does, there aren't many options for fixing this problem available.
High Moisture content in the subfloor or below grade will almost always ruin a solid hardwood floor
With this said, there are options. A better alternative to solid hardwood is engineered wood that can be glued down to the concrete. Even then you will need to have a contractor use a moisture meter to address whether a hardwood floor of any kind can be installed. Prefinished engineered wood is recommended although you could go with an unfinished engineered hardwood as well. The unfinished product would have to be sanded down after it has been laid though.
Another common way to install wood flooring in the basement is to use a floating floor. Besides the fact that installing a floating floor is much easier than the nail down or glue down floors, the floating floor is probably the best solution. The reason behind this is that generally moisture problems in basements occur from either below the subfloor or through the walls and assuming that you are using a moisture barrier, common installation practices with a floating floor will protect the floor both ways.
You will need a vapor barrier to protect your wood floor from moisture in the basement regardless of what you choose
If you are going to use a hardwood floor glue, you will need to use a vapor barrier as well to "catch" the moisture between the concrete subfloor and the wood flooring to help prevent cupping, crowning or buckling. Some common vapor barriers include 15 pound roofing felt, 6 mil polyethylene sheets (both will be embedded into a skim coat of asphalt mastic) or PVC applied over the slab itself with some type of multipurpose adhesive. Bostiks MVP offers a great moisture barrier that can be applied via trowleling.
How to determine if your basement is a good candidate for hardwood floors
Since moisture is such an issue when it comes to installing flooring below grade, there are some things that you can look at to determine if you should even consider it at all. Now, while a moisture meter is definitely the way to go when determining what type of flooring will work best in the basement, there are some things that you can do to determine whether you should go even that far.....
Questions to ask:
- If there are appliances such as a washer or dryer in the basement, does it show any signs of rust, ie. rust on or around the actual appliances?
- Does it have a perimeter drain trough that leads to a sump pump already?
- Does the basement sell "moldy" or "mildewy"?
- Do you notice any water spots or damp spots on the walls?
- Are you walls "chalky" or showing signs of peeled paint (assuming that your basement is painted)?
- Are you currently using a humidifier or dehumidifier in the basement?
- Are there any signs of mold on the walls or around the perimeter?
If you answered yes to any of these questions, then you will need to identify the source of the moisture and eliminate it before installing your wood floors. A lot of times, this may mean tearing down the existing framework of the walls and adding foam board insulation to prevent the walls from exuding moisture. Don't seal the floor joists as this will allow the vapor barrier to breathe.
Another thing to consider is to add a fan to the basement as cirulating air will reduce the chances of mold growing.
Now, supposing that you don't have any moisture issues and your subfloor is flat and level, you will have to either find an alternative wood floor like laminate or use engineered hardwood for your basement slab. You will also have two choices as far as installation goes:
- Free floating Engineered Hardwood Floors
- Glue Down Hardwood Floors
The free floating floor is perhaps the easier of the two if you are doing it yourself and it works below grade because the whole floor moves (expands and contracts) as a whole as opposed to single sections reacting to enviromental changes.