Roofing 101: The Parts of a Residential Roof

Shingles or metal panels are the most visible part of a roof, but they work together with underlayment, flashing and ventilation to protect your home. Here’s what those parts do and what to look for in a roofing proposal.

The covering: shingles, panels or membrane

Shingles, metal panels or a membrane such as TPO form the roof’s main weather barrier. The right covering depends on the roof’s slope, design and exposure, as well as the look you want.

Underlayment

Underlayment sits between the roof covering and the deck, providing a secondary layer of protection. We use synthetic underlayment and install it according to the product requirements, including limits on how long it can remain exposed.

Ice and water shield

Ice and water shield is a self-adhering membrane used in vulnerable areas such as eaves, valleys and roof penetrations. It is designed to seal around properly installed fasteners and help protect against water that gets beneath the roof covering. Placement depends on the roof and the installation requirements.

Flashing

Flashing directs water away from joints, walls, chimneys, skylights and other roof transitions. These details need particular care because gaps and damaged flashing can let water into the home. Our replacement proposals include new flashing, with the details matched to your roof.

Drip edge

Drip edge is the metal along the roof’s outer edges. It directs water away from the fascia and decking and helps protect those edges from moisture.

Pipe flashing

Plumbing vents need flashing where they pass through the roof. Some use a rubber gasket that can crack or deteriorate with age and exposure. We check these seals during an inspection and explain whether a repair is needed.

Vents and ventilation

Roof ventilation allows air to move through the attic. Along with insulation and air sealing, it helps manage heat and moisture. Ice dams can involve several factors, so ventilation alone is not a guarantee against them. We look at the roof and discuss any attic-related concerns we find.

Decking

The plywood or boards everything is nailed to. You can’t see it until tear-off. If we find rot under an old roof, we stop, dry the roof in, and call you before going further.

What to ask a contractor

When you compare proposals, ask about these layers by name: what underlayment, where the ice and water shield goes, whether the flashing is new, and what happens if the decking is bad. A bid that only names the shingle brand and color is only telling you about the part you can see.

See materials and colors, or request a free inspection and we’ll show you which of these your roof needs attention on.