The valley is formed where the two different sections of the roof meet generally at a 90 angle.
Roof valley framing details.
Trussed valley set detail no sheathing continuous 2x4 sp no 2 attached to the roof 146 basic 160 ultimate mph wind speed.
The roof construction for mortarless valleys is similar to that for open grp valleys.
On the common rafters the plumb cut is marked with a framing square for a 12 in 12 pitch 45 and cut square i e no bevel.
Not shown are the hip and valley rafters needed to tie the roof together where the rafters are framed at an angle to each other.
Instead of having an open channel like traditional valleys mortarless valleys have a central upstand and the tiling is finished close to the upstand on each side.
The rafters carry the applied loads to the exterior walls.
Shingles should overlap the valley lining by at least 6 inches.
The function of each component is.
The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle.
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.
With a metal liner nail 1 2 inch outside the liner.
Therefore the pitch of the valley rafter is 12 in 17.
The run or half the building span is the base of the triangle.
The rise or height of the roof at its peak is the altitude of the triangle.
The first cut that i make on both the common rafters and the valley rafter is the plumb cut where the rafter will meet the ridge board.
Seal each shingle to the liner and overlapping shingle with a 3 inch wide bead of plastic roofing cement.
In a rafter roof all of these components are required to provide a stable roof.
Prescriptive roof consisting of the rafters a ridge board ceiling joists and collar ties.
This type of roof is more complicated than the figure 2 1 most common types of pitched roofs.