Secondary to having a strong foundation is having a good roof. A roof must be able to carry snow loads and shed water away from a building.

There are different types of roof and the most common you see in Nova Scotia are gable, hip, shed, and gambrel.

A gable roof is a simple triangle with two sides or faces. Hip roofs have four sides. A shed roof can be almost flat, but has some pitch to it. It has grown some popularity over the past 10 years on more modern designs, and a gambrel is what you would normally see on barns.

The type of roof you choose for your home is more of an aesthetic choice, so much so that you can have different types applied into one building to give it more depth and character.

There are also different types of roof finishes, the two most commonly used here are shingles and metal. 

Asphalt Shingles

Shingles are typically made of paper, fiberglass, and petroleum products. They are the most economical option and their lifespan according to manufacturers is 30 years. Typically, they won’t last that long and it would have to be replaced after 15-20 years. 

Shingles come in bundles, and three bundles cover 100 sq ft. Each “sheet” in the bundle is about 12”x36” and comes with a predetermined exposure (part of the sheet, also called tabs, that is exposed after the next course of shingles has overlapped the previous course).

Each sheet has a strip of adhesive in the nailing area (remember to peel the plastic off before laying it down), it is often not enough to secure it in places like the east coast of Canada where we get high winds. Putting additional tar on the underside of the exposed tabs will act as an adhesive to ensure that the wind doesn’t pick up the shingle and tear it off the roof. 

Shingles are fastened with roofing nails which will be hidden when the next course is installed. For obvious reasons, you want to minimize if not eliminate exposed fasteners when installing finish roof as it is an avenue for water to get in which will then cause leaks.

Metal Roof

Metal roofs would be the best choice when it comes to finish roofs. They may be pricier than the previous option, but their lifespan can outlast the building itself if installed properly. They come in about 36” in width and precut in length from the manufacturer according to the roof specs of the building. There are also different types of metal roof – screw down and standing seam.

Screw down panels have a corrugated profile and are installed on the rib of the panel using colour-matched self-tapping screws with a rubber gasket. Screws must not be driven too far in that it squishes the gasket , or too loose that it leaves a gap. Careful attention must be given when installing each screws. Each panel must be screwed on each rib every two feet creating multiple holes on the panel increasing the likelihood of water penetration if screws are installed incorrectly or the gasket has failed overtime.

Standing seam are installed with big head screws on the flange that will be then hidden when the next sheet is installed eliminating any possibilities of water penetration through screw holes. Standing seam has a cleaner look and requires additional work when being installed as the bottom of each panel has to be bent using a special hand tool and crimped into the drip edge.

The Roof Prep

Before any sheet of roofing finish is installed, some preparation must be done. A drip edge must be installed at the bottom of the roof to shed the water away from the sub fascia. A type of underlayment must be laid down to provide a secondary protection if the finish roof fails or any ice damming occurs. Ice damming occurs when a snow melts and freezes again creating a dam for water to get in under shingles or into any roof penetrations. Valley flashings (valleys are intersections on the roof) and eave starter are then installed. Eave starters go on the sub fascia that goes to the peak of the roof. They serve the same purpose as a drip edge. After these components are installed, you are pretty well on your way to install the finish roof.

The Install

The installation process is pretty straightforward no matter the type of finish you use, however, please make sure you snap a chalk line to ensure the straightness of materials you are using. Also ensure you are using the right kind of fastener. 

With shingles, you want to install them to go over your drip edge and eave starter about ½”. This keeps the water from getting in between the shingle and the flashing. 

With metal roofs, when all the panels are installed, a gable flashing is installed at either ends of the roof to provide a nicer finish as well as to keep water from these exposed ends.

At the peak of the roof, also called the ridge, there must be at least a 2” opening from the peak to the edge of the sheathing on both sides. This enables venting of the attic which is important to keep the attic the same temperature as the outside at all times. This helps mitigate ice damming and provides air flow into the space. Different roofing finish will have its own ridge components. For shingles, a plastic venting must be installed on the ridge before the ridge cap is installed and for metal roof, the ribs provide an opening for venting and a polyethylene closure (something that looks like the green kitchen scrubbie but more open to keep dirt and bugs from coming through) is installed.

Tips

1. DO NOT DO IT if you can avoid doing it. Leave this to the professionals who have the gear, know what they’re doing, and enjoy the back pain at the end of the day. The roof is one of the most uncomfortable places to be. You’re at least 10 feet off the ground constantly walking on a steep slant. It’s hard on your ankles, your hand, your knees, and your back. If you have no idea what you’re doing, you’re more akin to making mistakes creating more problems in the future.

2. If you’re going to be stubborn about it, PLEASE WEAR A FALL ARREST AND USE IT PROPERLY. Your gear can only effectively save your life if you are using it properly.

3. Consider a lower pitched roof in your design if you’re adamant. A 4/12 is manageable and a 6/12 is pushing it. Any more than that is straight up crazy.

4. In any horizontal overlap on your flashing, use sealant. Remember you want to eliminate any possible entryway for water.

The best advice I can give is #1 above. Roofing work is no joke. You do it once you’ll know right away how hard it is and why it costs a good dollar to hire a reputable company to do it. The higher you are off the ground, the more risks there are. At the end of the day, are the risks worth the money you pay someone else to do it?