R Values Of Roofing Materials

Or area temperature difference time heat loss.

R values of roofing materials.

R value measures how well certain building insulation materials can resist heat. Because the system is spray applied and adheres directly to the roof surface no fasteners are required. 3 85 per inch polyiso. In construction the r value is the measurement of a material s capacity to resist heat flowfrom one side to the other.

The higher the r value the greater the effectiveness of the insulation. R value of roofing materials and building insulation. Pitch angle of roof the pitch of the roof angle can be a considerable factor when replacing your roof. R value of building materials material r inch r thick ness fiberglass inch 3 00 1 inch 4 00 inch 6 00 extruded polystyrene inch 3 75 1 inch 5 00 1 inch 7 50 foil faced polyisocyanurate inch 5 40 1 inch 7 20 1 inch 10 80.

Without a doubt sprayed polyurethane foam will provide the highest r value and best insulation for your flat roof replacement. The higher the r value the greater the insulation performance. In simple terms r values measure the effectiveness of insulation and a higher number represents more effective insulation. 10mm 13mm 07 077.

Asphalt shingles have an r value of around 45 while wooden shakes or shingles carry an r value of 97 or more than double its competitor. An insulating material s resistance to conductive heat flow is measured or rated in terms of its thermal resistance or r value defined as ft f hr btu. Know exactly how much you need with our project calculators. For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15.

The material offers the highest r value on the market and has no fasteners in the surface to allow thermal bridging. Air film interior ceiling 14. The average r value for some common roof materials include. R value per inch ft f hr btu rsi per millimeter k m w r value for typical installed thickness not per inch source.

The r value depends on the type of material its thickness and its density. 5 0 per inch eps insulation. Built up roof membrane gravel surfaced membrane and gravel only 0 33. Air film interior wall 14.

Here s a useful r value calculator for roofs. Or square feet degrees fahrenheit hour btu. Material thickness r value m2k w permeability 50pa notes. Other materials can be reflective including restoration coatings and most single ply systems but this is not the same as being a good insulator.