Roof Insulation Dimensions

In most wall applications you will use r 13 or r 15 kraft faced fiberglass insulation rolls for these two by four stud walls.

Roof insulation dimensions.

The standard tapered panel size is 4 x 4. Since modern two by fours are not 4 inches the true depth of the wall cavity is 3 1 2 inches. R value is used as a measurement of the effectiveness of thermal insulating materials. Insulation for 2x4 walls most wall assemblies especially those in older homes are built with two by four 2x4 studs.

Types of roof insulation. Standard material is johns manville enrgy 3tapered and flat polyisocyanurate roof insulation. R value table for roofing materials and building insulation. Location of r value on a product data sheet.

When correctly installed tapered insulation helps eliminate problems due to ponding water and can extend the longevity of your low slope roofing system. The higher the r value the better a material performs as a thermal insulator. 4 x 8 1 21 m x 2 44 m service temperature limits 100 to 200 f 73 3 to 93 3 c. Eight inches of poor quality insulation may have a higher and better r value than one inch of top quality insulation.

The same insulation will hold more heat the thicker it is installed.