Valley Pitch Angle = 29.01714°
12/12 Main Span Angles Common Rafter Pitch Angle = 45.00000° Plan Angle = 33.69007° Sheathing Angle = 43.31386° Jack Rafter Side Cut Angle = 46.68614° Backing Angle = 36.03989° Valley Rafter Side Cut Angle (Peak) = 30.24146° Valley Rafter Side Cut Angle (Foot) = 52.67946° 8/12 Dormer Angles Common Rafter Pitch Angle = 33.69007° Plan Angle = 56.30993° Sheathing Angle = 60.98286° Jack Rafter Side Cut Angle = 29.01714° Backing Angle = 17.92021° Valley Rafter Side Cut Angle (Peak) = 52.67946° Valley Rafter Side Cut Angle (Foot) = 30.24146° |
Saw Blade Bevels for the Valley Rafter cheek cuts are complementary to the Plan Angles.
The Saw Blade Bevel for the Jack Rafter cheek cut is the same as for the cheek cut at the Valley Rafter foot. The Jack Rafter Side Cut Angle and Sheathing Angle are complementary. |
12/12 Main Span Jack Rafter Difference in Length
If spacing on centers along Valley ridge line = 16" Difference in Length = 16" × tan 43.31386° = 15.08495" = 15 ^{1}/_{16}" 8/12 Dormer Jack Rafter Difference in Length If spacing on centers along Valley ridge line = 16" Difference in Length = 16" × tan 60.98286° = 28.84441" = 28 ^{7}/_{8}" |
Valley Pitch Angle = 12 × tan 29.01714° = 6.65640 = 6 ^{11}/_{16} 12/12 Main Span Plan Angle = 12 × tan 33.69007° = 8.00000 = 8 Sheathing Angle = 12 × tan 43.31386° = 11.31371 = 11 ^{5}/_{16} Jack Rafter Side Cut Angle = 12 × tan 46.68614° = 12.72792 = 12 ^{3}/_{4} Backing Angle = 12 × tan 36.03989° = 8.73128 = 8 ^{3}/_{4} Valley Rafter Side Cut Angle (Peak) = 12 × tan 30.24146° = 6.99580 = 7 Valley Rafter Side Cut Angle (Foot) = 12 × tan 52.67946° = 15.74054 = 15 ^{3}/_{4} 8/12 Dormer Plan Angle = 12 × tan 56.30993° = 18.00000 = 18 Sheathing Angle = 12 × tan 60.98286° = 21.63331 = 21 ^{5}/_{8} Jack Rafter Side Cut Angle = 12 × tan 29.01714° = 6.65640 = 6 ^{11}/_{16} Backing Angle = 12 × tan 17.92021° = 3.88057 = 3 ^{7}/_{8} Valley Rafter Side Cut Angle (Peak) = 12 × tan 52.67946° = 15.74054 = 15 ^{3}/_{4} Valley Rafter Side Cut Angle (Foot) = 12 × tan 30.24146° = 6.99580 = 7 |