Roxul For Roof Rafters

R value measures how well certain building insulation materials can resist heat.

Roxul for roof rafters.

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. Not only do we withstand hail damage but our roof boards maintain their bond to the roof membrane lowering the likelihood of a catastrophic roof failure. All roof rafters should be identical so follow the same steps to measure the plumb cut tail cut and birdsmouth cut. When determining how much insulation you need don t guesstimate calculate.

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. Code specifies the minimum r value of the rigid foam layer. Rigid foam on roof sheathing with air permeable insulation between the rafters. Installing stone wool insulation in the attic space of a low slope roof can provide increased thermal efficiency.

The higher the r value the greater the insulation performance. 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. Rafters are commonly spaced about 24 inches 61 cm apart. Rigid foam also can be installed above the roof sheathing in tandem with air permeable insulation between the rafters.

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. The spacing between rafters in a given building is part of the engineering calculations that determine the required structure of the roof.