Exterior Roof Insulation Detail

The attached file shows a roof detail for an icf house planned for omaha nebraska.

Exterior roof insulation detail.

It typically has 3 variations. Exterior insulation keeps the framing warm and dry by moving the insulation outside the framing the chances of condensation are almost eliminated. You ll see that the top chord of the 30 roof trusses rests on the icf wall. Foamular xps roof insulation for commercial buildings page 5 foamular xps roof insulation for commercial buildings foamular xps insulation is a rigid foam insulation which meets the needs of today s design professionals for a truly sustainable insulation product.

Owens corning insulation products help improve thermal performance and control moisture in commercial institutional and. Plywood or osb roof sheathing can be installed over exterior insulation layers using long exterior grade screws. Some people worry that using impermeable sheathing in a cold climate will trap moisture within wall cavities. Another benefit is that you can get a superinsulated roof without increasing the size of the rafters or furring the framing down and encroaching on the living space.

Impermeable foil faced sheathings like dow tuff r or rmax r matte plus are good choices. Exterior roof insulation retrofit unvented roof covering the roof of an old house with a blanket of insulation makes the house more comfortable and it cuts energy use. The previous four options are all used beneath the roof. Rigid foam board is just above the roof deck or an exterior insulation option.

It makes a lot of sense if the rafter cavities are already insulated and it is most affordable when the roof needs replacement. Our insulation provides a range of products and solutions for exterior wall systems such as rainscreen cavity wall exterior continuous insulation curtain wall wood frame and metal frame constructions. Between the trusses and sill pieces i intended to use sill sealer and spray foam to keep the joint between the top of the wall and roof deck airtight. 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.

First the foam will increase thermal performance by adding r value and minimizing thermal bridging. An unvented roof cladding substrate e g. 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. Tightly sealed exterior sheathing functions as an important air barrier detail in any climate but can be critical in a hot humid one.

The benefits of adding a layer of rigid foam insulation to the exterior of walls and roofs are twofold.