Roof Insulation R Value 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.

Roof insulation r value canada.

Insulation level are specified by r value. The table below shows what levels of insulation are cost effective for different climates and. For a very good introductory overview article on r value see r values over at the website of. 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.

One method involves installing rigid board insulation on top of the existing roof see figure 5 25. 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. R value of various materials. The two distinct types of attic insulation are loose fill material also commonly known as blown in insulation and batting.

The recommended r value for attic insulation in ontario is between r 50 and r 60. Recommended home insulation r values. R values of common types of insulation. If the nominal thermal resistance of the cavity insulation being used falls between two specified rsi r values the lower value must be applied i e rounding up is not permitted.

The frame cavity component tables indicate eligible surface air films or roof air spaces that may be included in the continuous layers of rsi series determined in. The r value of the insulation for every inch of thickness depends on the type of insulation. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. In such cases where r value is assigned this may decrease the r value requirement for batt insulation.

The increase r21 r3 exactly 18 the value by which you are increasing the r value. Calculate percent improvement in r value. Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. R value is a measure of insulation s ability to resist heat traveling through it.

I calculate insulation resistance to heat loss or r percentage improvement always as relative to the original number. The higher the r value the better the thermal performance of the insulation. R3 r18 r21 total roof r value. Firestone isogard polyiso insulation goes even further and was the first product on the market to meet both astm c1289 required and recommended thermal performance values.

For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3.