Spray Foam Insulation (interior application)
Spray polyurethane foam (SPF), or spray foam, can expand up to 100 times its original size. The product is designed to fill every corner of your home’s envelope, providing the most effective thermal insulation and air sealing barrier possible.
Spray foam insulation is applied mainly in:
The most common application is in the attic space where SPF insulation is the most effective.
The two choices of SPF insulation are closed cell and open cell foam. The difference is in the density of the foam. Closed cell means water cannot pass through the foam. Open cell is light and as the name implies, open cell, which means water can pass through the foam.
What Is Spray Foam Insulation?
Insulation contractors combine two liquids to initiate a chemical reaction that creates urethane foam insulation. These liquids arrive at the job site in separate containers and are typically referred to as the “A” side and “B” side, the “A” side and “B” side ingredients mix together to form a third, completely different material.
The “A” side is commonly a mixture of methylene diphenyl diisocyanate (MDI) and polymeric methylene diphenyl diisocyanate (pMDI). The “B” side is typically a polyol and smaller amounts of other liquids, including the foaming agent polyola. The other liquids include catalysts, blowing agents, surfactants and flame retardants.
How Is Spray Foam Insulation Applied?
Once the chemicals are mixed, they react quickly and the foam hardens. The length of the reaction depends on the type of SPF insulation and other variables. The insulation is applied with a heated high pressure sprayer the emits the mixed chemicals as foam.
Contractors apply interior, two-component SPF while wearing personal protective equipment. Use of a respirator is required when installing high density foam. This equipment, coupled with certain work practices and engineering practices including ventilation, help minimize exposures to the chemicals used to make SPF during the job.
Contractors provide guidance about when you can reenter your home after an interior foam insulation application. Minimize or eliminate exposure to the chemicals used to create spray foam by carefully following your contractor’s vacancy-length guidelines during the installation, job completion, and cleanup.
What are the advantages of Spray Foam Insulation?
Spray foam insulation is flexible, with variations of the product available for a variety of uses. For instance, some types of spray foam allow water to pass through the insulation. Other types of spray foam repel water completely.
Spray foam remains where it is installed. Unlike fiberglass, it does not settle. Spray foam’s air sealing qualities help reduce the amount of dust, allergens and pollutants entering your home, helping to protect you and your family from allergies.
Traditional insulation can be dusty and could allow allergens and other pollutants to enter your home which can trigger allergies and respiratory issues like asthma.
Most fiberglass contains formaldehyde, and may emit formaldehyde fumes into your home. Unlike fiberglass insulation, SPF insulation is impervious to pests.