If the roof has a triangular shape stretch your tape measure along the bottom edge then measure from the peak point down to the center of the bottom edge.
How to shingle peak of hip roof.
After both hips were finished the guys would place a shingle along the ridge.
Start by overlapping a starter from both sides of the valley at the bottom.
For trapezoidal roofs measure the bottom edge the top edge also known as the ridge and the distance between the 2 edges.
As you place each new row make sure the center of the next shingle up overlaps the previous row by 2 3 of the total length.
Determine the width of the shingle pieces and snap a line a little less than half that dimension on one side of the hip or ridge peak then align the side of the shingles along that guide.
The hip shingles continued all the way to the ridge and that last shingle was cut to length so as to avoid covering the open ridge rafter.
There are a number of key steps you need to take to avoid mucking this part up.
The guys would cut a second shingle to overlap the back half of the first one.
Weave and cut the valley on the highest side of the roof.
The starting shingles for each row will typically be halved at the ridge of the hip roof as you ascend.
You will also want to place them on top and do your best to center them on a seam between two on the previous row.
Then your first shingle goes on the side you are going to cut.
Use the shears or utility knife to cut three tab shingles into three separate shingles to use as cap shingles for the hip roof.
Adjust the bottom of the felt if necessary to keep it flush with the gutter apron.
Three bundles of three tabbed shingles equal one square or 100 square.
Step 4 continue rolling out the felt until you reach the roof hip on the other end.
Insert staples with a hammer stapler 12 inches apart along the top and bottom edges of the felt paper as you roll it out along the roof.
This is an area of the roof which requires extra care and skill.