Roofing systems · Toronto & the GTA

Roofing systems — compare a good roof from a cheap one.

Two roofs can use the same shingle and last twice as different. The shingle is the part you see; the system underneath is what survives a GTA winter. Here is exactly what a real roof is made of, what each layer does, and where cheap bids cut corners.

A roof is seven layers — not just shingles

From the deck up. Read it like a cutaway: every layer below does a job, and skipping any one of them is how a roof that looks finished still leaks in three winters.

1. 1

   Roof decking (sheathing)

   The plywood or OSB surface everything is nailed to. Soft or rotted sheets must be replaced — this is the #1 hidden cost, billed in Ontario at about $3–$6 / sq ft replaced. It is invisible until tear-off, so a cheap "fixed" quote often excludes it.

2. 2

   Ice & water shield

   A self-sealing waterproof membrane at the eaves and in the valleys — the spots where GTA freeze-thaw drives ice dams and backed-up melt. Skimping here is a common cheap-bid shortcut that causes interior leaks.

3. 3

   Underlayment

   A synthetic moisture barrier over the rest of the deck. Cheap bids quietly downgrade synthetic to old-style felt, which tears and absorbs water.

4. 4

   Starter strip

   A purpose-made sealed first course along the edges that locks down the bottom row against wind uplift. Some crews skip it and cut up field shingles instead — it voids the wind warranty.

5. 5

   Shingles

   The visible field — 3-tab, architectural, or designer / Class-4. This is the layer homeowners see and compare, but it is only one part of the system.

6. 6

   Ridge cap

   Matched, thicker caps that seal the peaks and hips. Like starter, these are a defined product — not field shingles bent over the top.

7. 7

   Ventilation

   Balanced intake at the soffits and exhaust at the ridge. Without it, attic heat and moisture cook the shingles from below and shorten the roof’s life — even a top shingle fails early on a poorly vented deck.

Three complete systems — every component listed

Pick a roof like you'd pick a phone plan: good, better, best, with nothing hidden. Each price is a planning range per square foot, installed. Your verified number is confirmed after a photo-backed assessment — never before.

For context, a typical detached GTA architectural replacement lands around $15,000–$20,000 + 13% HST. GTA labour and disposal add roughly 15–25% over the rest of Ontario, and deck replacement (the #1 concealed cost) is named up front, never sprung on you. We install to manufacturer specification — as a year-one company we don't claim certifications or awards we haven't earned.

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