There is a significant price difference when it comes to using foam insulation to insulate a new versus older home. Spraying insulation inside a newly constructed home is easier because the installation company can ensure the insulation will work effectively and design it for optimum defense against sound, heat transfer and utility costs. Installing spray foam in older homes that contain existing insulation can cost additional time and money -- it is not usually recommended as compared to weatherization or an energy aduit.

Closed-cell (aka two-pound foam) is denser than open-cell at about 2 pounds per cubic foot. Its R-Value is between 6-6.5 per inch. As a result, this kind of foam is much more expensive than its counterpart. The reason closed-cell doesn't need a vapor retarder is because it already has one. It's permeance is 0.8 perm, which means it can handle cold climates without the use of an additional board or drywall. Closed-cell uses hydroflurocarbons (HFCs) as part of its makeup. However, this material has been known to have a high global warming effect. If you want a green insulation solution, this is not the material to use. A way to avoid this and still use closed-cell is by installing it alongside fiberglass batts.
SPF, a spray-applied cellular plastic, is made by mixing chemicals to create foam. Those chemicals react very quickly, expanding on contact to create foam that insulates, air seals and provides a moisture barrier. When properly installed, SPF forms a continuous barrier on walls, around corners and on contoured surfaces. It resists heat transfer very well and is an effective solution for reducing unwanted air infiltration through cracks, seams, and joints.
Fill and seal expanding foam sealant is urethane Fill and seal expanding foam sealant is urethane foam designed to fill large areas quickly and permanently. Uses include filling holes cracks or gaps that require a complete airtight and waterproof seal but are too large to be filled with ordinary caulk. The foam expands approximately 3 times its original ...  More + Product Details Close 

Roof Coating Seal