It additionally seals round nails, which retains water from leaking by way of nail holes. If you need extra air flow, minimize further vent holes in the decking with a circular noticed and set up vent flashing. Installing shingles round attic vents, plumbing vent stacks and furnace stacks is mainly the same process.
Install the second course identical to the primary, utilizing the rules on the underlayment to get the correct overlap. When an ice dam varieties on a roof (often attributable to poor attic insulation/ air flow), ice and water can work their means up under the shingles and leak again into the house. Also, robust winds can blow rainwater underneath shingles. Self-stick roofing underlayment (often referred to as “ice-and- water” underlayment) can prevent this because it sticks to the roof decking to seal out water.
Finally, nail the first course of shingles instantly on prime of and flush with the starter course. Use four roofing nails per shingle, as indicated on package deal instructions (six nails in high-wind areas). Once this course is laid, you possibly can begin snapping horizontal chalk traces up the roof to ensure straight rows. of the shingle tabs the place the underside edge of the tab meets the highest of the cutout. Snap chalk lines to assist maintain the row of ridge cap shingles straight.
Call your constructing inspector for native particulars. Position them so the adhesive strip is towards the underside and dealing with up. Water can get within the seams between any two shingles, but that’s OK as a result of shingles overlap and the seams are staggered. But should you don’t use starter shingles, water will run in between the seams on the primary row and right onto the underlayment, growing the chances of a leak. The starter row shingles are solely half as extensive as a full shingle. If they have been full measurement, the top half of the primary row would have three layers of shingles instead of the two the remainder of the roof has, inflicting a visual hump.
Windblown heavy rain and/or snow can drive water up and under even properly put in shingles. Buy it at roofing provide corporations or house facilities. In severe climate areas, most constructing codes require applying it three to 6 ft. up from the eave (minimum of 2 ft. previous the exterior wall).
It’s unimaginable to correctly install new flashing and underlayment when you don’t tear off the old roof beforehand. When tearing off the existing shingles, be sure to take away all the old nails or pound them flat. Protruding nails will tear holes in your new shingles. If you could have movable objects close to your home and also you’re apprehensive they might get damaged, relocate them.
Invest in a few large tarps to protect your crops and landscaping and to catch the thousands of nails that will rain down off the roof. It may be downright unimaginable to take away old self-stick ice-and-water underlayment, nevertheless it’s OK if you have to go away it in place. And if at all possible, have the rented trash bin parked close to the house so you can toss within the old shingles right from the roof.
Install the ridge cap so the prevailing winds blow over the overlap seams, not into them. Once all your shingles are put in, you may need to cover the ridge . The high ridge cap shingles will overlap the hip ridge cap, so start with the hips.
When installing the felt paper over a stack, it’s OK to make an oversize gap. But before you roll out the row of paper above the stack, cut a 2- or 3-ft. section of self-stick underlayment, reduce a gap in it barely smaller than the diameter of the stack, and slide it over the stack. Make positive the piece is giant enough so that the following row of felt paper overlaps the top at least a couple of inches .