Insulation Below Roof Deck

This variation on the unvented attic design requires a thermal barrier such as an approved intumescent coating.

Insulation below roof deck. How to attach rigid insulation on the underside of the roof deck. Below you will find links to company and product information for manufacturers and suppliers listed in the roof and deck insulation section of sweets. The ratio of insulation above the roof deck or air permeable insulation below the roof deck is a matter of climate and interior conditions. Hence the term cold decks construction materials wood based products absorb moisture.

Gaining in popularity is the design approach of insulating on the underside of the roof deck and leaving the spray foam exposed to the occupants below. The roof deck is cold wood decks without insulation above them will readily equilibrate to the exterior temperature. 07 22 00 roof and deck insulation. I would use polyiso with a top layer of eps as recommended in your blog post on the topic.

I m considering a roof design that would place all the insulation above the roof deck with no insulation below. This section outlines the conditions for unvented attic roof assemblies. Placing a layer of fluffy insulation below the roof deck would needlessly complicate the. With rising heating and cooling.

Note that table r806 5 indicates the amount of insulation above the roof deck or air impermeable insulation below the roof deck required for condensation control assuming minimum required total insulation as indicated in section n1102 building thermal envelope. The greater your home s thermal resistance factor or r value the more energy efficient it is.