Know exactly how much you need with our project calculators.
R value of roofing materials.
When buying various insulation materials you will almost always see an r value quoted for the material.
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.
In general higher r means more resistance to heat loss and therefore lower heating or cooling bills for the building.
To convert rsi to r value multiply the rsi by 5 67826.
In simple terms r values measure the effectiveness of insulation and a higher number represents more effective 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.
When determining how much insulation you need don t guesstimate calculate.
R values and heat loss.
The higher the r value the better a material performs as a thermal insulator.
R value measures how well certain building insulation materials can resist heat.
The r value of a material is its resistance to heat flow through the material.
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.
This webpage calculates the r value of walls roofs and suspended floors for most insulation material r values.
In construction the r value is the measurement of a material s capacity to resist heat flowfrom one side to the other.
Eps based claddings directly fixed on timber framing.
This comprehensive guide to roofing materials is all the research you ll need to evaluate the top choices for residential re roofing and new construction projects in 2020 what to expect.
In this guide we ll cover the following most common roofing options.
It uses the iso thermal planes method the same method as used in nzs4214 2006.
R value is used as a measurement of the effectiveness of thermal insulating materials.
Some of the possible material combinations may not be suitable for actual constructions i e.
The higher the r value the greater the insulation performance.
For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721.
To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826.
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.
Asphalt shingles wood shingles and shakes metal roofing concrete clay and fiber cement tiles natural and.
Rsi r value système international is the metric equivalent.
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.
Types of roof insulation.
