Whether it’s new construction or replacing an existing roof, roofing installation requires an expert and precise approach. Roofers must navigate residential neighborhoods, climb on ladders to access roofs and be mindful of surrounding property when installing or repairing the exterior layer.
To prevent moisture intrusion, a layer of protective roofing paper is applied to the sheathing. This is especially important in areas where leaks might occur, like at the chimney and around skylights or stack vents.
The preparation process for a roof installation starts with clearing the area around your home. This helps your roofers get to work without any obstacles and prevents them from tripping or accidentally damaging things that are outside your home. It also makes it easier for them to carry materials, deliver supplies, and remove the shingles once the job is finished.
In addition to clearing the yard of any outdoor items, you’ll want to clear off your driveway and sidewalks. This isn’t just a safety precaution for your family members, but it’s important to keep the work zone clear for everyone involved. This includes moving any cars, bikes, or anything else out of the way so that it’s safe for people to walk by. It’s a good idea to place them in your garage or another nearby parking spot so that they’re not in the way of the workers and can be easily moved later.
It’s also a good idea to take down any wall hangings, especially those on the top floor of your home. The vibrations from hammering and nail guns can knock items off your walls, so it’s best to be proactive and take down anything that you don’t want to lose. This includes mirrors, pictures, wreaths and loose shelving.
You’ll also want to cover any air vents, skylights and other ceiling penetrations. These can be damaged by the vibrations of hammers and nail guns and the dust that’s kicked up during the roofing process.
If you have children or pets, consider having them stay at Grandma’s during the reroofing process. This is because it’s a noisy and messy process that will interrupt naps and outdoor playtime.
Layout
The process of snapping vertical control chalklines for the shingle course layout and laying out the shingles in that pattern is called “layout.” Successful roofers follow the layout rules and never stray from it. A stray shingle course may end up with less overlap than intended or joints may be too close to each other, which increases the risk of leaks during extreme weather conditions. Using an intelligent pattern and layout allows the installer to produce quickly without having to think about each shingle or nail.
The typical shingle course is 5 inches long with 2 additional inches of headlap for insurance purposes, making it 10 inches total in length. This is a standard size and an excellent starting point for most roofs. It is a standard that provides the most overlap for water shed and provides a good safety margin against wind uplift damage.
Shingles
The shingles (a corruption of the word tiles) that cover roofs are available in a wide variety of patterns, textures and colors to suit aesthetic preferences and architectural styles. They provide a highly decorative appearance for buildings and can also protect the building from water and weather damage.
When installed, the shingles cover the roof and are held in place by nails. The shingle manufacturer provides instructions on proper nail placement and spacing, and on the degree of exposure and offset (the lateral distance between shingles in successive courses) that is appropriate for the shingle style. It’s important to follow these instructions because problems can arise if a shingle is exposed too much or too little, or if the edges of adjacent shingles are not correctly offset. These problems can lead to leaks and roof failure.
Shingles are made of paper or fiberglass, wood, clay or a combination of materials. The latter are typically found on vernacular homes. They are often crafted of local material and may be of varying sizes and thicknesses, depending on the climate conditions in a region.
Clay shingles have been used for thousands of years, which is a testament to their durability and beauty. They add an earthy, natural look to a home and can enhance the charm of older houses. They’re also fire-resistant and help to keep the house warm. They are less expensive than a conventional shingle, but they require frequent replacement. Wood shingles are generally made of cypress, redwood or Western red cedar. They can be kiln-dried or hand-split resawn to prevent warping. Wood shingles are relatively decay resistant, but they are more susceptible to wind-borne debris and are more likely to be damaged by rain than other types of roofing.
Flashing
Flashing is thin, corrosion-resistant metal bent into shape to seal a joint or protect a protrusion on a roof. It’s installed where roof leaks are prone to occur, such as at a roof valley where two downward slopes meet or around any object that penetrates a roof, including chimneys, skylights and vents. Flashing also prevents rain water from entering walls and causing damage. It’s usually made from aluminum or galvanized steel and may also be copper, lead or PVC.
Step flashing is a type of roof flashing that creates a watertight seal around objects that penetrate the roof, such as chimneys or skylights. It involves installing a series of metal flashing pieces in “steps” along the object, overlapping each one to direct water away from the penetration and towards the roof’s edge. It’s used in conjunction with roofing underlayment, sealants and counterflashing to ensure a watertight seal.
Dormer windows are another type of roof protrusion that requires flashing. This is typically done by creating a custom piece of flashing that fits over the dormer. To do this, a square piece of standard step flashing is cut into, about halfway, and then bent at an angle to fit the dormer. The base of this piece is nailed to the roof and the top is covered by a ridge shingle.
Vent pipe flashing is another common type of roof flashing, usually made from either copper or PVC. It’s designed to protect the area around vent pipes, which are typically located in a home’s attic and help with proper air circulation. In most cases, this flashing is a bit more complicated than other flashing because it includes an overlap that protects the area from rain and other weather elements.
Ridge Cap
The very top of your roof receives intense sun and wind exposure, so it needs added protection to prevent moisture penetration. Without a ridge cap, moisture would seep in through the seam at the peak, causing costly damage including unhealthy mold, mildew, rot and more. Ridge caps not only prevent the passage of damaging moisture, but also protect your roofing system from water and other weather elements.
The ridge cap process involves installing a strip of shingles along the ridge line, overlapping each other and sealing to each other and to the roof panels below. A ridge cap is available in both vented and solid styles, with both options offering advantages and benefits depending on your climate.
Vented ridge caps have a baffled design that helps hot air escape your home, while keeping rain and insects out. They are usually a bit wider than solid ridge caps and fit over the ridge and sit slightly above it.
To install the ridge cap, center it on your building peak and mark both ends on the roof with a piece of chalk. Next, put down a strip of sealant tape along the ridge, around 1 inch above your chalk lines. Once your ridge cap is placed, fasten it to the closure strips using screws or roofing nails (check manufacturer instructions for proper nail size).