Insulating Underside Of Roof Deck

However architects of these compact roof assemblies must consider vapor permeance and arrangement of the materials to produce acceptable hygrothermal performance and low risk of condensation in the resulting conditioned attic space.

Insulating underside of roof deck.

Polyurethane spray foam metal roof insulation in order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam. Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls. Staple plastic or foam baffles to the roof sheathing near the eaves to keep the material away. A wood deck roof system.

It will help you to eliminate problems that may come when the house becomes extremely cold in the winter and terribly hot in the summer. In addition to installing the foam board on the underside of the roof deck you can attach it to the bottom edges of the rafters in the same manner you would hang drywall. For the same reason insulation shouldn t touch the roof s underside. Insulation and air barrier are applied directly to the underside of the roof deck are common in applications where designers are seeking cost effective and energy efficient roof assemblies.

You can then install. For some building uses the ceiling might be absent. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic. Insulating the underside of deck.

This type of system can also be found in low slope residential buildings in inner city areas. This construction approach was first used in the 1970s and it has been implemented much more widely since it was first included in the international code council s icc model building code in 2007 irc section 806 4. If you re insulating from scratch put the right vapor barrier in the right place. It is about three feet off the ground and has mesh stapled to the underside to prevent bugs from making their way in.

Low slope and steep slope unvented roof systems i e. Fiberglass insulation is installed between the rafters as shown schematically below.