Continue to chalk additional guidelines based on the width of the shingle through at least four courses rows across the roof.
Roof asphalt shingle installation.
Above 85 f it is easy to tear the shingles or mar the granular coating.
Below 40 f shingles are brittle and crack easily when hammered or bent.
Installing asphalt shingles over an existing shingle roof it s not ideal to install new shingles without removing the old ones but follow this pro advice if you do.
Starting at the bottom of the roof map out a guideline with chalk.
Although placing new roofing over old may be allowed by some codes roofovers tend to be inferior and won t last as long as a roof installed over stripped sheathing.
Then begin nailing the shingles to the roof working in rows and starting at the edge of the roof.
The felt is laid in horizontal courses overlapping the eave ice and water protector by 4 and the valley membrane flashing by 6.
While the asphalt shingles will be the primary water shedding roof layer there are many benefits to installing a roof underlayment.
Installation temperature requirements for asphalt shingle roofs ideally shingles should be installed at temperatures ranging from 40 f to 85 f.