Choosing the right kit for your project
Spray foam can generally be purchased in three main density categories, with the standard density also being available as fast rising or slow rising. Some of them are referred to with a few different names, so it can get confusing to know which one is the best choice for your project. Foam it Green has all 4 types of foam available – closed cell high density, closed cell standard density fast rise, closed cell standard density slow rise, and open cell low density.
Standard – Fast Rising Closed Cell – Our Foam it Green 602 and 202
Standard density foam is referred to as such because it is the most commonly used type of foam amongst the most projects. Because it is “fast rise” foam, it can be sprayed in any direction to an open cavity, where it will bond and expand. This is the most often used type of foam because it is “closed cell” which means it will stop air, stop moisture, and deliver a high R value of approx. 7 at a thickness of one inch. The density of closed cell Foam it Green is 1.75 pounds per cubic foot, which is why you may hear it referred to as “2 pound foam”. It’s ideal for a wide range of projects such as walls, floors, attics, metal buildings, rim joists, and more! Foam it Green closed cell formula is also ASTM E84 Class 1 Fire-retardant insulation, ASTM G21 Anti- microbial, and a Class 3 Vapor Retarder at 3”. The Foam it Green 602 kit has enough component in it to cover 602 squared feet at one inch cured, and the 202 enough for 202 squared feet at one inch cured.
Standard – Slow Rising Closed Cell – Our Foam it Green 602SR and 202SR
Slow rise foam is meant to be sprayed into an enclosed cavity, where the expansion will be delayed, allowing it to travel more thoroughly to where it needs to go, filling in all the gaps you can’t see. Slow rise Foam it Green is also Class 1 ASTM E84 Fire-retardant insulation, just like our fast rising formula. Slow rise foam is best installed into an empty cavity without any prior insulation still there. Since the estimated coverage with slow rise foam is based on “free rise”, you should estimate a bit more waste than you would with fast rise foam. Some of the slow rise foam might be held back from fully expanding, being trapped by the structure of the cavity or even other areas of already cured foam. In addition, since you cannot control the thickness of the spray with slow rise – the entire void must be filled. In a 2×4 wall construction, this means you will have about 3.5” of closed cell foam, which offers a tremendous R value, but at a higher per square foot cost. Alternatively, fast rise foam thickness can be controlled, and in many areas 2” of closed cell foam is sufficient. The Foam it 602SR Slow Rise kit has enough component in it to fill 600 squared feet at one inch cured (or 300 squared feet at two inches and so on) or 50 cubic feet, free-rise. The 202SR has enough to fill 200 squared feet at one inch cured or 15 cubic feet, free-rise.
Open Cell – Our Foam it Green 1202 and 402
Low density foam is more commonly referred to as “open cell” foam. The cell structure of open cell foam is such that the cells are less tightly packed and are not all fully closed which makes this density less ideal for applications that encounter moisture. Low density open cell foam is “spongier” than the other foams which makes is a better choice for sound deadening or air stopping between two temperature-controlled areas. Another name you may hear used for open cell foam is “half pound foam” which directly refers to its density. Foam it Green open cell formula is actually 0.75 pounds per cubic foot, making it a bit more dense than true half pound foam and giving it an R value of approx. 4 at a thickness of one inch. In addition, our open cell formula is ASTM E84 Class 1 Fire-retardant insulation. The Foam it Green 1202 kit has enough component in it to cover 600 squared feet at two inches cured, and the 402 enough for 200 squared feet at two inches cured.
High Density Closed Cell – Our Foam it Green 602HD and 202HD
High density foam is usually referred to exactly as “high density” foam. This type is also closed cell, but even more tightly packed so that it can withstand direct contact with water and even foot traffic. It is a fast rising foam than can be sprayed in any direction to an open surface. Since this is most often applied to surfaces going underground or on the outside of a building, it is not fire retardant insulation, and will also need to be protected by a coating that can keep UV rays from breaking down the foam over time. The bump you get in R value is only about 10% over the standard closed cell foam, at approx. 7.7 per inch. So, since this foam is about 50% more expensive than the standard foam, your return on investment with it in a regular project doesn’t warrant using it other than when it is specifically called for. With an ultimate density of 2.8 pounds per cubic foot, it’s no surprise you may sometimes hear this referred to as “3 pound foam”. It’s important to note that some may refer to all closed cell foam as “high density” foam, so it’s best to be specific and discuss the density directly when planning a project. Because of the increased density, the Foam it Green 602HD High Density has enough component in it to cover 396 squared feet at one inch cured, and the 202HD enough for 120 squared feet at one inch cured.
When in Doubt Contact Us!
Most projects are best suited to be attacked with closed cell foam. While it is initially more expensive, that increase in density will reward you with more structural stability, a higher R value, and moisture stopping power.
Still have questions about which foam might be best for your project? Just give us a call so we can have a project expert walk you through it – 1-833-FOAM-IT-G