Successful roofing application requires that installers adhere to certain proper application methods. It is especially easy for inexperienced roofers and do-it-yourself homeowners to make certain roofing application mistakes simply because they are not aware of the various things that can go wrong. Here is a list of some of the most common mistakes and what can be done to avoid them, thus ensuring a successful roofing project.
Mistake: Not including the starter strip.
Problem: This does not provide the proper shingle application base.
Fix: Apply starter shingles at the rake, continuing along the eaves. The starter shingles should be cut to match the existing first course’s exposure. For new construction shingles, this means a measurement of nine inches. Three-tab repair shingles should measure five inches. Then about six inches off the length of the first shingle should be trimmed to stagger the shingles out from the first full course.
Mistake: Not ensuring that the shingles overhang at the eaves.
Problem: This could contribute to roof blow-off.
Fix: Make sure that the shingles overhang the eaves and rakes by at least one-half of an inch. There should be a spacing of about one-sixteenth of an inch between the shingles. Finish nailing three inches above the eaves, using the proper number of nails according to the geographic wind zone.
Mistake: Not properly aligning the shingles.
Problem: This is not at all aesthetically pleasing.
Fix: Vertical and horizontal shingle alignment will be required. This is best done in new shingle applications by using the chalk line. In repair application, the new shingles should be aligned with the shingles that are already in place. Horizontal chalk lines should be set every 10 inches from the bottom of the first course up. Vertical chalk lines should be set every 36 inches from the roof ridge to each shingle’s end, along the first course.
Mistake: Not properly nailing the shingles.
Problem: This could potentially lead to roof blow-off.
Fix: Follow the manufacturer’s recommendations in installing the proper number of shingles for the specific geographic wind zone. Four nails will be required in typical applications of three-tab shingles, but six nails will be required in areas where the wind velocity gets very high.
Placement of the nails is as important as the number of nails being used. Look at the manufacturer’s required placement areas to assess proper placement of the roofing nails. Drive the nails straight into the deck, never nailing from an angle if at all possible.
Know what nail length is needed before roofing application is attempted. Nails should penetrate the deck by at least three-quarters of an inch. Standard roofing nails with barbed shanks are typically 11-gauge or 12-gauge and have heads with diameters anywhere between three-eighths and seven-sixteenths of an inch.
Mistake: Using asphalt-based cements for shingle repair.
Problem: Use of incompatible materials contributes to further shingle damage.
Fix: Apply asphalt-based cement only on the underside of shingles. Damaged shingles with evidence of curling, cracking, opening, or splitting should all be replaced with brand new shingles.
This brief list represents just a few of the things that can go wrong in roofing application. Before attempting anything of this nature on their own, homeowners should consult with the professionals at United Home Experts, who can provide much needed information and advice about the best ways to repair and/or replace a roof and provide free estimates on complete roof replacement.