Roxul For Roof Rafters

When determining how much insulation you need don t guesstimate calculate.

Roxul for roof rafters.

Providing high quality insulation between cathedral ceiling roof joists is an easy method of improving the overall energy performance of a building. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. Rigid foam on roof sheathing with air permeable insulation between the rafters. Code specifies the minimum r value of the rigid foam layer.

Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. R value measures how well certain building insulation materials can resist heat. Installing stone wool insulation in the attic space of a low slope roof can provide increased thermal efficiency. Exceptional dimensional stability and rated for extreme hail rockwool stone wool insulation roof boards have meet both the fm severe hail and the ul 2218a standard for impact resistance.

The higher the r value the greater the insulation performance. Rafters are commonly spaced about 24 inches 61 cm apart. In this case the rigid foam can be thinner than when it s used alone. Rigid foam also can be installed above the roof sheathing in tandem with air permeable insulation between the rafters.

Other relevant factors include the type of wood being used for the rafters the size of the rafters and the load that the rafters need to support. All roof rafters should be identical so follow the same steps to measure the plumb cut tail cut and birdsmouth cut.