Almost everyone who owns a house with an unfinished basement, dreams of having it finished. How can you not think of it? After all, an unfinished basement is a whole floor’s worth of space that can be easily turned into any type of room your family needs.
However, basement finishing projects are hardly inexpensive and, because basements are like no other room in the house, there are special challenges when it comes to choosing the best finishes and configuration. Basements usually house utilities, plumbing, wiring. They are also quite prone to moisture and water accidents. All of which must be taken into consideration before you tackle your project. Making the wrong choices, can literally spell disaster.
Below are the six most common mistakes homeowners make in basement remodeling projects:
1 – Finishing a Wet, Damp or Flood Prone Basement
Because of the way they are built, basements are always prone to moisture and floods.
Your basement is basically a box of porous concrete, buried in wet ground, and when that ground gets saturated with water, the resulting hydrostatic pressure pushes the water against the foundation walls. That water will eventually find its way into your basement, through cracks, the joint between walls and floors, as infiltrating the concrete through capillary action. To make matters worse, basements can also be flooded by plumbing leaks, broken water heater tanks and other water accidents. Without proper drainage, a reliable sump pump system, and proper dehumidification, no basement is dry enough to be finished.
2 – Using wood studs, fiberglass insulation and drywall.
While these materials work well when finishing rooms above grade, in a basement they usually spell disaster. Basements are naturally humid, and all these materials have the tendency to absorb moisture. They are also made with organic compounds: wood, paper and, in the case of fiberglass, a urea based adhesive is used to hold the batch together.
When you combine moisture with organic matter, you create ideal conditions for mold to develop. In addition, fiberglass loses all its R-Value when damp and drywall, in contact with water, will begin to decompose and release toxic fumes. Basement walls should be finished with 100% inorganic and waterproof materials that will survive a basement flood or water accident.
3 – Using wooden subfloors, hardwood floor, cork or bamboo.
Basically, anything that is made with organic materials is a bad idea for basements. Manufacturers might tell you that these products are either naturally “mold resistant” or are chemically treated to be so. Some wooden basement subfloor manufacturers might claim that the product has a vapor barrier and it is raised from the floor to keep the wood from soaking the moisture from the slab. However, read the small print. None of them really stand a chance to survive a flood, which can be caused by a plumbing leak, for example. Look for basement flooring solutions that are specifically engineered to withstand all sorts of basement moisture conditions.
4 – Improper use of vapor barriers
Many contractors will tell you that if you attach poly sheets all over the walls and the floor of the basement, you can pretty much use any type of finish you want, because the “vapor barrier” will protect the materials. Some will have an even worse suggestion: Placing the vapor barrier over the studs and the fiberglass, and then attach the drywall. According to the US Department of Energy’s Building America Best Practices recommendations, moisture from basement walls and floors should be allowed to evaporate and dry to the interior. This kind of vapor barrier will only do one thing: trap the water vapor between the concrete and the barrier, where it can condensate, and can cause mold to grow.
5 – Not having a backup sump pump
Every year in Wisconsin, millions of dollars are spent on basement flood cleanup, restoration and replacement of flood-damaged property. To make matters worse, the damage is never covered under homeowners insurance, and even special flood insurance establishes coverage limits when it comes to basements. Even if your basement is properly waterproofed and has a good working sump pump, without a battery operated backup sump pump, you are at risk for a basement flood. Keep in mind that the same storms that have the potential to flood your basement can also cause power outages. No power, no pump! Battery backups are also useful in case of a primary pump failure or other electrical malfunction.
6 – Disregarding moisture control.
You did all the right things when finishing your basement. You provided drainage, a good sump pump with battery backup. You chose all the right materials for the walls, floor and ceiling. Yet your basement smells musty or you found some mold spots growing in the furniture, fabrics or paper. Although proper waterproofing and good basement finishing choices can greatly improve conditions in the basement, in some cases they will not suffice to control the moisture in the basement.
Basement moisture levels tend to be higher because of temperature differences between the basement and the areas above grade. When basement moisture levels go above 60% mold will start to develop, especially in organic surfaces. Even if you don’t see it, if the basement smells musty, the mold is present. Basement moisture levels should be closely monitored and a dehumidifier should be used to keep RH levels at or below 55%.