Finished Basement Insulation
I’m preparing to “finish” one of the rooms in the basement. The room is actually going to be a storage room so I use the term “finish” with a grain of salt. I plan on building some shelves to store some of our “junk” that has accumulated in the portion of the basement that will one day become a family room. The storage room will be approximately 12’x14′ and it’s in the front corner of the house that has full 8′ high concrete walls. Before I build any shelves I want to build two walls in front of the concrete walls and insulate them. Before finishing your basement I recommend you get this book, Black & Decker Complete Guide to Attics & Basements.
Recommended Basement Insulation Method
Insulating the concrete walls will drastically improve the overall energy efficiency of the house. In my opinion the best way to insulate a foundation wall is the following:
1. Apply an extruded polystyrene foam insulation board (I happen to use “blue board” that DOW makes) to the concrete wall. You can apply the foam insulation board to the wall using a couple of methods; using an adhesive or shooting 1×3 strapping into the concrete wall to hold the insulation in place. I plan on using an adhesive. There are two types of adhesive, one comes in a caulking tube and it generally says foam insulation adhesive or you can use Great Stuff spray foam.
2. Tape all the seams with a tape that is appropriate for adhering to foam board. I like to use Tyvek Tape. The tape helps keep moisture from getting to the wood framing.
3. Build a 2×4 stud wall just in front of the foam board insulation. Fasten the bottom pressure treated plate to the concrete with powder actuated fasteners and nail the top of the wall to the floor framing.
4. Insulate the wall with R11 fiberglass insulation.
For my scenario I plan on using 1″ of blue board (R=5) and R11 fiberglass for a total R = 16. I’ll write a post in the next day or so about my progress.
Check out the followup post, Complete Guide To Insulating Basements.