Spray Foam Insulation: Creating a Warm Unfinished Space
Unfinished spaces that are going to stay unfinished are the easiest areas to insulate. With nothing that can be damaged or has little to no aesthetic value, the insulation can literally be applied on all of the surfaces. This method of insulation is called a "monolithic thermal blanket." The monolithic thermal blanket can be achieved in a flat attic with blow in cellulose insulation that covers all of the ceiling joist and drops into every little nook and cranny. With walls, floors, ceilings, and roof bottoms, the only material that will perform this is closed cell spray foam insulation.
Creating a Monolithic Thermal Blanket
When performing this insulation technique on a typical framed structure, fill framing cavities first also you would if you were going to apply a finished surface to the area. The minimum amount recommended for the inside of the cavities is 3 inches which equates to and R-21. After the cavities are filled with the closed cell spray foam insulation, insulate the framing as well with a skim coat of spray foam. This covers all of the framing surface virtually eliminating most of the thermal loss or gain that will occur.
If you are insulating a non-framed surface such as a foundation wall or concrete floor, take special care to makes sure that surface is clean and free of dirt or dust. The one thing that spray foam will not stick to is dirt or dust and negate the entire purpose of using the spray foam. This type of surface is easier to create your monolithic thermal blanket because non framed surfaces are flat. The 3 inch rule still applies in this case.
Where can I Purchase Spray Foam
You can purchase spray foam insulation kits online in 600 and 200 board feet kit sizes. The kits range in price from $500 to $800. You can also call a local insulation distributor. Be cautious when purchasing these kits and make sure that you are purchasing a "closed cell spray foam kit" and not an open cell kit as the open cell spray foam is not appropriate for this type of installation.
Creating a monolithic thermal blanket will significantly decrease your energy loss and gain in a space and save you energy overall.