Insulation Roof Eaves

In cold climates thin insulation near the eaves contributes to ice dams.

Insulation roof eaves. The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow. Detail to show the buildup of new loft insulation to the underside of an existing eaves installed internally to allow ventilation of the existing roof over the new insulation. The best approach in these situations is to use an insulation with a higher. If you have a wall ceiling roof construction whereby you need to insulate the ceiling up to the roof membrane then you have to install rafter vents to allow air to continue to flow.

Covering up the soffit vents with loose fill or batts which can happen if you stuff insulation along the eaves is a huge no no. You may not be able to see them clearly yourself but you can be sure that your hard earned hot air will. In most of the u s. Design the roof to allow full insulation over the top plates of the exterior walls.

A minimum ventilation gap of 25mm is to be provided over the loft insulation to allow sufficient ventilation at the eaves. To be truly effective insulated areas must be tied down to the roof itself at the eaves. For the same reason insulation shouldn t touch the roof s underside. This is the point where the roof meets the walls of the house and it s one place where small gaps and cracks are commonly found.

Everywhere but climate zone 1 building codes require the installation of ceiling insulation rated at r 38 or r 49. You need ventilation in the attic a good crossflow of air will keep the attic space dry. The materials used to insulate under the roof include batts of mineral or glass wool insulation held in place by battens of wood attached to and across the rafters.