The rise or height of the roof at its peak is the altitude of the triangle.
How to add a peak on a roof.
Nail the trusses into the existing room fasteners.
For your first row of shingle at the bottom of the roof place a shingle piece with the solid side overhanging the drip edge feels upside down by 1 4 and install using roofing nails.
Cut two rafters with a circular saw to the pitch of the addition roof and nail them across the rafters on the old roof.
Create the slot by cutting through the sheathing along each chalk line on either side of the peak.
Step 4 re sheath roof.
They form an upside down v with the point at the top of the addition roof.
Cut it to size using a box knife and install with a staple gun.
Step 1 calculate the roof span.
Start by installing tar paper on top of the plywood.
The run or half the building span is the base of the triangle.
Rather than a single slope a gable roof consists of two slopes that meet at a peak running down the middle of the roof.
Step 2 calculate material prices.
The total run is the distance from the peak to the edge of the roof which in this case is the total width divided in half which is equal to 10 feet or 120 inches.
And the line length measurement from the roof peak to the building wall is the hypotenuse.
Calculate how much the roof span is going to be by measuring from one top plate to the other top plate.
Set the power saw s blade depth to the thickness of the sheathing and any remaining shingles about 3 4 inches to 1 inch.
When matched to the angle and proportions of other rooflines on the house your gable roof will add visual interest and character to the home making the addition look like an asset that belongs with the house.
Now you can begin shingling your roof preferably with asphalt shingles.
Since pitch is the rise over a 12 inch run divide the run by 12 to get the multiplier in this case 120 12 10.
The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle.
Adding pitch to a flat roof.
Once the trusses soffit and fascia are in place lay the roofing felt in place.