We like the looks, fire resistance, and permanence of metal roofing to replace our asphalt shingle roof. Will metal transmit heat and cold more than asphalt shingles? What percentage of increase might we expect in utility bills if we don't add insulation?
Wesley T. ~ Waco, Texas
To go from asphalt roofing to a metal roof, will have virtually no effect on your utility bills. The R-value of asphalt shingles is .44 and depending on who you talk to and the style of metal roof you intend to install, you will have an R-value between .1 and .61. The metal in the roofing material has an R-value of 0, but the airspace between the metal and the roofing felt does have some R-value. This is why it is hard to accurately determine the R-value of metal roofing.