Basement Floor Insulation

Basement Insulation

Most basements are built with the cement floor in direct contact with the cold moist ground. Unfortunately this type of basement floor construction does not lend itself to creating a comfortable basement.

Concrete will absorb moisture, like a sponge, and the result is an uncomfortable musty basement. A musty basement does not make a comfortable or healthy living space. The additional water moisture introduced into the home can also lead to mold issues. Finding a way to keep water out of the basement will greatly improve the smell and health of the home.

Heat is also lost through basement floors. The notion that heat always rises isn't entirely true. Heat will flow towards any relatively cooler place. If the ground under the basement floor is cooler than the basement temperature, as it is in almost every climate year round, heat will naturally try to escape through the concrete slab into the earth below it.

Creating an insulation layer and a vapor barrier between the concrete slab and the ground beneath it is the best practice in insulating basement floors. The insulation barrier will help keep warm air in, and the vapor barrier will keep unwanted moisture out.

How to insulate a basement floor:

Spread the base gravel under the basement slab so it is level and approximately one inch lower than the conventional method. This will provide adequate space for the insulation and a vapor barrier.
Place a one inch layer of 4 x 8 foot polystyrene foam over the gravel, covering the entire floor area.
Tape the joints between the pieces with builder's tape to create a tight insulation layer.
Place 5 mil. polyethylene over the foam boards. Be sure to overlap it at least 6 inches at the seams. Make sure there are no gaps, tears, or holes in the polyethylene. Repair any you find with builder's tape. This covering will act as the vapor barrier.
Tape the polyethylene joints with builder's tape and your ready to pour the concrete.

Basement floor insulation will make your basement a much more pleasant living space by keeping out moisture and keeping in the heat.

Basement Moisture Problems

Basement Lighting

Building Basement Walls

Building a Half Wall

Framing a Finished Basement

How to Prevent Basement Flooding

Installing a Dehumidifier

Insulating Finished Basements

Painting Basement Concrete Walls

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