موضوع: flame-retardant

When you compare price to R value per sq ft the price is about the same. The classic version has a thermal resistance (R value) of 3.7 per inch and other versions have even higher values. It has an R-value of around 3.7 (RSI-0.65), equivalent to the median value for fiberglass batts. Some fiberglass is unfaced, some is paper-faced with a thin layer of asphalt, and some is foil-faced. Materials with one shiny side (such as foil-faced polystyrene) must be positioned with the shiny side facing an ...