R Value Calculator
Before Heating/cooling off for at least 60 minutes Sun not shining on outside surface Ideally large inside/outside temperature difference Steps Measure temperature of an inside wall, bed head, funiture, ideally facing into room at same height as wall near the wall Measure the wall/floor/ceiling Measure outside air temp Calculator Surface Type: Wall Ceiling Floor Temperature Units: Celsius Fahrenheit Inside Ambient Temperature Inside Surface Temperature Outside Ambient Temperature Calculate Results Indoor Air Film Convection Transfer W/K/m2 Indoor Air Film Radiation Tansfter W/K/m2 Indoor Air Film R Value (SI) m2·K/W Indoor Air Film R Value (Imperial) ft2·°F·15/BTU Heat Loss (SI) Heat Loss (Imperial) Estimated R Value (SI) m2·K/W Estimated R Value (Imperial) ft2·°F·h/BTU