R Value Of Roofing Materials

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.

R value of roofing materials.

It s important to think about r value when considering your roof project because by increasing the r value you allow your roof to keep warm air in during the winter and out during summer. Know exactly how much you need with our project calculators. The higher the r value the more insulation the material provides by limiting airflow between outside and inside the building. R values and heat loss.

Rsi r value système international is the metric equivalent. In simple terms r values measure the effectiveness of insulation and a higher number represents more effective insulation. 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 siding materials hardboard inch 0 34. When determining how much insulation you need don t guesstimate calculate.

R value table for roofing materials and building insulation. Asphalt shingles wood shingles and shakes metal roofing concrete clay and fiber cement tiles natural and. Types of roof insulation. R value measures how well certain building insulation materials can resist heat.

Some of the possible material combinations may not be suitable for actual constructions i e. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721. The higher the r value the better a material performs as a thermal insulator. When buying various insulation materials you will almost always see an r value quoted for the material.

The higher the r value the greater the insulation performance. R value is used as a measurement of the effectiveness of thermal insulating materials. In this guide we ll cover the following most common roofing options. In construction the r value is the measurement of a material s capacity to resist heat flowfrom one side to the other.

This webpage calculates the r value of walls roofs and suspended floors for most insulation material r values. In general higher r means more resistance to heat loss and therefore lower heating or cooling bills for the building. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. The following table is in metric form.

It uses the iso thermal planes method the same method as used in nzs4214 2006. To convert rsi to r value multiply the rsi by 5 67826. Click here to go to our calculator to understand the real r value of a ceiling system or wall system with gaps in the insulation. There are many websites on the internet which have imperial building material r value numbers but not so many with metric r value numbers.