Roof R Value Calculator

Includes multi unit residential buildings.

Roof r value calculator.

Class 2 high rise apartment a building containing 2 or more sole occupancy units each being a separate dwelling. It uses the iso thermal planes method the same method as used in nzs4214 2006. Our calculator helps you measure what r value for exterior walls you may be looking for as well as for different applications. This calculator is to be used as an estimating tool only.

Remember the horizontal or vertical orientation of the material is important to get its insulation value correct. This webpage calculates the r value of walls roofs and suspended floors for most insulation material r values. Some of the possible material combinations may not be suitable for actual constructions i e. R value is a measurement that rates how resistant a product is to heat flow measuring the ability of heat to transfer from one side of an object to another.

To calculate the total r value of a roof assembly find the total thickness in inches of each type of insulating material within the system. Eps based claddings directly fixed on timber framing. The r value calculator is best used as follows. Input depth of existing blown in insulation in inches.

Add the results for all the materials together to get the total r value for the roof assembly. For each different material multiply the thickness by the standard r value per inch for that material.