Start by overlapping a starter from both sides of the valley at the bottom.
How to start shingling your roof.
Using your chalk line snap a line down the center of the valley.
See below for a shopping list tools and steps subscr.
Starting at the bottom of the roof map out a guideline with chalk.
Continue to chalk additional guidelines based on the width of the shingle through at least four courses rows across the roof.
A continuous bead of asphalt could trap condensation or windblown water under the roofing at some point.
The next one goes on the low side.
Move to the other section of the roof then start laying shingles just like you did on the other section of roof.
After completing a column the roofer can go back down to the eave edge of the roof and start laying the next column of shingles.
Next find the center of the roof at the top and the eave then snap a vertical chalk line.
This saves a lot of time moving shingle bundles and a lot of back strain.
Both step shingling and racking will yield a watertight roof.
The felt keeps the roof deck dry before shingles go on protects against wind driven rain as shingles fail and increases fire resistance.
Here are the basic steps to shingle a roof.
You want to lay the shingles from the bottom to the top of the valley.
Build your shingles up to the highest part of the valley at the ridge.
Nail the shingles with no tabs such as precut pro start shingles and apply asphalt cement from a caulk gun in many dots along the drip edge under the edge then press the tab less shingles down onto the line of asphalt cement dots with adequate spaces between the dots.
Not only that the shingles can be piled just to the side of the column being laid.
Use your chalk and tape measure to mark about 12 inches up on the roof for the first set of shingles.
Step one in any roofing project is always safety first.
Weave and cut the valley on the highest side of the roof.
Iko recommends that roofing work be done by qualified professionals who know the best way to shingle a roof and have been fully trained in all aspects of roof construction safety.
This will provide a cutting guide for the shingles you will place on the other side of the valley.
Working at heights on a roof presents fall hazard risks and other safety concerns.