Open-cell foam is a type of foam classified by its physical structure. R-value of open cell foam is around 3.5 per inch, Pore sizes of open cell foam range from 0.5 to 3mm, and the pores are connected or completely connected, creating a single-dimensional or three-dimensional structure through which gases and liquids can pass.

Open-cell foam has a low R-value of around 3.5 per inch while closed-cell foam boasts a higher R-value of around 6 per inch. Despite having a lower R-value, open-cell foam can provide effective insulation but may be more challenging in extreme climates.

Open cell foams have an R-value of around 3.5 per inch. This is significantly lower than closed cell foams, which can limit open cell insulations usefulness in extreme temperature conditions.