Reroofing terminology

Reroof, overlay, tear-off: decoding Gresham roofing proposals

Roofing has its own vocabulary, and contractors don’t always use it the same way. “Reroof” is the most slippery word. Some use it for any new roof. Others use it specifically for an overlay, where new shingles go on over the existing layer. Building codes sometimes use “reroofing” broadly, covering both approaches. When a proposal says “reroof,” the only safe assumption is that you need to ask what it means on that page.

An overlay (sometimes called a recover or layover) keeps the old shingles in place and adds a new layer on top. It avoids tear-off labor and disposal, which lowers the price. It also hides the decking, leaves old flashing either reused or awkwardly layered, adds weight, and means two layers have to come off at the next replacement. Some roofs can’t be overlaid at all, and some manufacturer warranties treat overlays differently.

A full tear-off removes all existing layers down to the deck. It costs more in labor and disposal, but it allows the deck to be inspected and repaired, new underlayment and membranes to be installed directly on it, and flashing to be rebuilt at every wall and penetration. When you compare a tear-off bid with an overlay bid, you are not comparing two prices for the same thing — you are comparing two different jobs.

Other terms are worth pinning down too. “Replace as needed” for decking means little without a unit price. “Flashing included” could mean new metal or resealing old metal. “Ventilation” could mean new ridge vent and intake, or simply reinstalling the existing box vents. Asking for each term in writing turns a vague proposal into one you can compare.

Terms to clarify on any Gresham proposal

“Reroof” — overlay or full tear-off?
“Tear-off” — all layers, or just the top one?
“Decking as needed” — what is the per-sheet price, and who approves it?
“Flashing included” — new metal or reused, and where?
“Ventilation” — new intake and exhaust, or reinstalled existing vents?
“Cleanup” — does it include a nail sweep of the yard and driveway?

Repair or replace

Repair, overlay, or full replacement?

There are really three options on the table, and the roof’s condition decides which is reasonable.

Often still a repair

Localized damage on a roof with flexible shingles and no sign of deck problems
A single leak traced to a flashing or vent detail
The roof is relatively young and the damage came from one event

Points toward replacement

The shingles are worn across the roof, and there is already more than one layer
There are signs of soft or damaged decking that an overlay would hide
Flashing at walls and chimneys needs rebuilding, which an overlay can’t do well

Moss, stains, or a roof’s age alone don’t settle the question, and remaining life can’t be promised from a photo. An on-site roof inspection is the way to know. See also roof repair vs. replacement.

Scope

What a full tear-off scope in Gresham should list

A tear-off scope should leave no doubt about the method: every existing layer removed to the deck and hauled away. It should then name each part of the rebuilt system, from decking review and underlayment to flashing, ventilation, edges, and shingles. Damaged decking is photographed and reviewed with you before it is replaced, at the per-sheet price stated in the estimate.

Permits: requirements depend on the city or county with authority over the property — which isn’t always the city in the mailing address — and on the scope, such as whether sheathing or framing is replaced. Ask whether your project needs a permit and who will obtain it before work is scheduled.

Items your written scope should cover

Removal of all existing roofing layers to the deck
Hauling and disposal of the old roofing
Decking review and per-sheet replacement price
New underlayment applied directly to the deck
Membrane at valleys and penetrations where specified
New flashing at walls, chimneys, and skylights
Ventilation described by type and location
Shingle line, color, and a nail sweep at cleanup

Cost factors

Why Gresham reroofing bids can be far apart

The single biggest gap between bids is usually method. An overlay skips tear-off and disposal, so it prices lower; a full tear-off includes removing every layer and hauling it away. Beyond method, the measured roof area, pitch, access, valleys and penetrations, flashing scope, ventilation, and the shingle line selected all move the number. A roof with two existing layers costs more to tear off than one with a single layer.

Decking is the unknown that only a tear-off reveals. An overlay bid never encounters it, which is part of why it looks cheaper. Our tear-off estimates list decking at a per-sheet price and show damaged sections to you before replacement. That makes the potential added cost visible rather than hidden under a new layer.

More detail: what affects roof replacement cost and what a roofing estimate should include.

Gresham bid comparison checklist

Is each bid an overlay or a tear-off? Get it in writing.
How many existing layers does each bid assume?
Is disposal included?
Is decking priced per sheet?
Is flashing new, and where?
What do the warranties say about overlay versus tear-off installations?

Process

How a Big Bear roof replacement runs

On-site estimate
A roofing specialist walks the roof, checks shingles, flashing, and ventilation, takes photos, gathers measurements, and emails you a detailed estimate.
Review and sign
You go over the written scope and options. When you are ready, you accept the estimate online with an e-signature and we schedule the installation date.
Tear-off and installation
The crew protects the property, removes the old roof, reviews the decking with you where repairs are needed, and installs the new roof system.
Cleanup and follow-up
Debris is hauled away, the property is checked for nails and scrap, and you receive follow-up messages and photo documentation of the work.

Preparing your Gresham home for tear-off

Tear-off is the loudest, messiest part of the project. These steps help.

Leave room for a dumpster or trailer close to the house
Move cars, grills, and patio furniture away from the eaves
Cover items in the attic or garage that could catch falling dust
Let neighbors know about the noise and the work days
Keep pets inside and away from the work areas

The roof as a system

What goes into a complete new roof

Big Bear focuses on steep-slope asphalt shingle roofs, including architectural shingles and designer lines such as GAF Grand Sequoia. We don’t install flat or low-slope roofing. Exact components depend on your roof’s design, applicable code, and the manufacturer’s instructions.

Decking

The plywood, OSB, or board sheathing the roof is fastened to. It is checked once the old roof is off.

Underlayment and membranes

A water-resistant layer over the deck, with self-adhering membrane at vulnerable areas where specified.

Flashing

Metal at walls, chimneys, valleys, and skylights that turns water back onto the roof surface.

Roof edges

Drip edge at eaves and rakes, and starter courses that seal the first row of shingles.

Penetrations

Pipe boots, vents, and other openings, each sealed to suit the new roof.

Shingles

Architectural or designer asphalt shingles, installed to the manufacturer’s instructions for your roof’s pitch.

Ventilation

Intake and exhaust that suit the attic. What a given roof needs depends on its design, code, and the manufacturer.

Single-story ranch home with a new dark gray roof, white board-and-batten siding, and a cedar porch — A single-story ranch roof replacement by Big Bear Exteriors in Vancouver, WA.

Who you’re working with

Big Bear Exteriors serves homeowners in Gresham, OR from our office at 1104 Main St, Ste 610, Vancouver, WA.

Washington L&I # SERDEGL826PD · Oregon CCB # 239429
Licensed general contractor in WA & OR · Bonded & insured

You can check our registration with the Oregon CCB. How our workmanship coverage and manufacturer warranties differ is explained on our warranty page.

Nearby service areas

See residential roof replacement or all service areas. Not sure about your address? Contact us.

FAQ

Roof replacement questions from Gresham, OR homeowners

Does reroofing mean an overlay or a full tear-off?

It depends on who’s using the word. Some contractors say reroofing for any new roof; others mean an overlay of new shingles over old ones. Ask each contractor to state in writing whether the existing roofing will be fully removed to the deck. If a proposal is an overlay, ask how decking, flashing, and future removal will be handled.

Is an overlay ever a good idea?

It can be allowed in some cases and costs less up front. But it hides the deck, limits how well flashing can be rebuilt, adds weight, and leaves two layers for the next replacement. Some manufacturer warranties also treat overlays differently. For most worn roofs, a full tear-off is the more thorough choice.

What does “decking as needed” mean?

It means damaged decking will be replaced when the roof is opened — but without a unit price, you can’t tell what that will cost. Our estimates state a per-sheet price, and damaged areas are photographed and reviewed with you before they’re replaced.

Will my ventilation be changed during reroofing?

It should at least be evaluated. Ventilation works when intake at the eaves and exhaust near the ridge are balanced for the attic. A replacement is the simplest time to correct problems. See roof ventilation for how it works.

Roof Replacement in Gresham, OR