Roofing Components 101

For a job that really requires a lot of strength and endurance, you wouldn’t think that there was much more to the job than back breaking labor. But the truth of the matter is a roofer has to know a lot of stuff to get the job done right. And that includes knowing lots of terms and jargon about the way a roof works and the components that are involved in its construction. Whether you’re hiring a roofing professional to do the job for you or you’re going to shingle your home yourself, know the following roofing terms to get the inside scoop on roofing.

Basic Roofing Materials

It’s a good idea to get to know your roof and the different components that make up the overall structure whether you’re doing the work or hiring a pro. The following common terms can help you to understand what each roofing component does and why it’s needed.

• · Underlayment- Once the plywood has been applied to cover the trusses, a protective layer of waterproofing material is needed to protect the plywood from direct contact with the roofing materials. The underlayment as it is called is typically made from an organic felt paper and is rolled over the top of the plywood. Some underlayment materials such as a snow and ice barrier offer additional underlayment waterproofing protection.
• · Flashing- The areas of the roof where two roof lines come together is known as a valley. These exceptionally wet locations do a lot of the work when it comes to shedding water and they especially need extra help doing so. Metal flashing is applied on top of the underlayment to protect water from entering these locations. In fact, flashing is applied to areas of the roof where walls, gable ends, skylights, plumbing stacks and other roofing penetrations are prevalent and the underlayment and shingles won’t completely do the job of keeping the roof dry.
• · Eaves Drip- Also known as drip edge, this metal banding is applied to the edges of the roof to protect the underlayment and plywood from water intrusion along its edge. It is similar to flashing with the exception that it won’t be covered by the shingles and will remain visible once the roof is complete.
• · Roofing Cement- Tar, mastic, bull, butyl-it’s got lots of names, but it only does one job besides sticking to everything-it keep water out. It’s used as solely as a waterproofing agent around roofing penetrations and underneath of flashing. It does the waterproofing job that shingles and underlayment can’t quite reach.
• · Ridge Vent- A ventilation outlet is needed for hot air and gases from the attic interior to escape. And since heat rises, this vent is placed at the top of the roof or ridge line. It is placed on the roof last and is covered with a final layer of shingle caps.
• · Caps- Where the ridge line of any two sloping surfaces come together on a roof, a ridge cap must be placed to prevent water access behind the shingles. These are smaller shingles that are nailed to the roof after the shingles have been attached.