When it comes to insulating your home with closed-cell foam, it is generally considered sufficient when 2 to 3 inches are sprayed. Open-cell foam on the walls would require at least 3 inches for effective insulation. Homeowners often think that the insulating properties of the foam increase with a greater thickness, leading them to request 10 to 12 inches of closed-cell foam for roof covering insulation. However, this is not always the case.
There is a threshold for effective heat resistance and exceeding the recommended thickness does not provide better insulation, only leading to a waste of money and a decrease in profitability. The R-value of closed-cell foam is 6.5 to 7 reais per inch and it is often used to insulate beneath slabs, ceilings, walls and roofs. It works better than other types of insulation due to its excellent air barrier, moisture resistance and steam retardation properties. By using the right type of spray foam with the required thickness, you can achieve an application that meets your goals.
In order to determine the best solution for your home, it is important to consult a professional spray foam insulation company. They will be able to assess your situation and determine the best thickness and type of foam for your needs.
How Much Closed-Cell Foam is Enough?
Generally, two closed-cell foam units on the walls and 2.5 units in the unventilated attic are sufficient. However, this may vary depending on the conditions and what you want to achieve. The RR-1001 states that 4% foam makes it possible to achieve effective insulation even under the worst conditions and that a darker covering material is required.Additionally, limiting the vapor transmission of the foam from the bottom too much carries a certain risk as 5% of typical closed-cell products reduce interior permeability to almost the vapor-tight range. At 2 years old, all HFC-blown closed-cell foams are class II vapor retarders and would at least somewhat protect the roof covering, but not necessarily the fiber insulation. Therefore, it is important to consult a professional spray foam insulation company in order to determine the best solution for your home.
