A minimum ventilation gap of 25mm is to be provided over the loft insulation to allow sufficient ventilation at the eaves.
Roof insulation eaves detail.
A notch is taken out of the rafter known as the birds mouth.
The next important aspect is to detail the eaves allowing adequate ventilation and simple methods to achieve this are indicated in figs.
The eaves detail shows where the roof members and coverings meet the wall of the dwelling.
Fix a rafter spacer tray to provide a clear air path between underlay and insulation.
Cad details document name pdf dwg download all cad construction details 37 1 mb 3 4 mb mc01 identification of roof areas 694 kb 167 kb mc01a single layer underlayment 678 kb 302 kb mc01b double layer underlayment 711 kb 322 kb mc02 vent pipe flashing 626 kb 349 kb mc03 valley.
Download dwg file.
The wallplate is then used to secure the rafter to.
Inside your home usually in the attic the eave is the angle where the roof meets the outside wall a good place for insulation as long as it doesn t get into the soffit the underside of the overhang.
Eaves detail the eaves detail shows where the roof members and coverings meet the wall of the dwelling.
Detail summary 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.
Smart vent a special roof eaves vent product that provides a 3 4 opening about 6 above the top of the roof.
The lower edge of a roof which projects beyond the face of the wall.
How to construct a roof with full insulation at the eaves.
Order and install oversized or raised heel trusses figure 3 or install site built rafters with raised top plates figure 4.
The cavity is closed with a proprietary cavity closer.
Venting solutions for roofs with no overhang or soffit.
Install special roof intake venting products that work at the lower edge of the roof decking underneath the first course of shingles.
In cool or cold weather moisture laden air drawn into the attic or roof cavity will leave its moisture as condensation on the roof deck underside or in the attic or roof insulation.
The wallplate is secured to the internal wall separated by dpc.
The cavity is closed with a proprietary cavity closer.
Open eaves with ventilating rafter tray.
The wallplate is secured to the internal wall separated by dpc.
8 23b allows any water which may have penetrated through the tile to run down the roof slope into the gutter in the normal manner.
If a sprocketted or bell cast detail is used then eaves courses should be no lower than the minimum recommended roof pitch.
Specify 2 to 2 foot overhangs which are higher providing more room for insulation at the top plate and additional window shading.