Roof Insulation R Value Canada

For a very good introductory overview article on r value see r values over at the website of.

Roof insulation r value canada.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. I calculate insulation resistance to heat loss or r percentage improvement always as relative to the original number. In such cases where r value is assigned this may decrease the r value requirement for batt insulation. You should of course see the manufacturer provided technical data sheet for the r value of specific products.

Know exactly how much you need with our project calculators. Depending on where you live and the part of your home you re insulating walls crawlspace attic etc you ll need a different r value. Conditioned per atsm c1289 test method astm c5181 2. When determining how much insulation you need don t guesstimate calculate.

R values of common types of insulation. The increase r21 r3 exactly 18 the value by which you are increasing the r value. R value of various materials. The recommended r value for attic insulation in ontario is between r 50 and r 60.

The higher the r value the greater the insulation performance. See the department of energy s doe ranges for recommended levels of insulation below. One method involves installing rigid board insulation on top of the existing roof see figure 5 25. Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces.

The two distinct types of attic insulation are loose fill material also commonly known as blown in insulation and batting. If installed uncompressed in a 152 mm cavity e g some manufactured framing products it will retain its full thermal resistance value of 3 52 m2 k w. The r value of the insulation for every inch of thickness depends on the type of insulation. Thickness inches r value in i p imperial rsi r value in metric 0 5.

Foam plastic insulation on the interior of the building envelope must adhere to the requirements of protection of foamed plastics as per 9 10 17 10 of the national building code of canada. The higher rsi value of rigid insulation means a smaller increase in the roof thickness although several layers of insulation may be needed to meet the desired rsi level. R value chart for enerfoil tm rigid foam faced insulation. An rsi 3 52 r20 per 152 mm batt compressed into a 140 mm cavity has a thermal resistance value of 3 34 r19.