You got three quotes for a new roof and they all look different. One has 8 line items, another has 20, and the third is a single number with "full replacement" written next to it. Here's how to read them.
The line items you should expect
Tear-off and disposal. This is the cost to strip the existing roof down to the decking and haul it away. Should include: removal of old shingles, underlayment, and flashing; disposal in a rented dumpster; cleanup and magnetic nail sweep. If the quote doesn't mention disposal, ask who's paying for the bin.
Decking repair. This is usually listed as an allowance or a per-sheet price (e.g., "$85/sheet of OSB if needed"). Good quotes include a small allowance rather than springing a surprise change order. We include up to 2 sheets in our quotes — if more is needed, we text you a photo and get approval before proceeding.
Underlayment. The water barrier that goes between your decking and shingles. Should specify the product: synthetic felt or peel-and-stick. If the quote says "felt paper," that's the old way — synthetic is better and not much more expensive.
Ice-and-water shield. Self-adhesive membrane for eaves and valleys. Ontario code requires it 3 feet from the eave. Some quotes include more (we do 6 feet). This is one of the most important lines — skip it and you're asking for ice dam leaks.
Drip edge. Aluminum or galvanized edge flashing. Some quotes include it, others don't mention it at all. It should be replaced on every full re-roof. If it's not listed, ask.
Shingles. Should specify the brand, product, and colour. "Architectural shingles" is not specific enough — "GAF Timberline HDZ in Charcoal" is.
Flashing. Step flashing at walls, counter flashing at chimneys, valley treatment. This should be explicitly listed. Flashing shortcuts are the #1 cause of post-install leaks.
Ridge vent and cap. Ventilation at the peak. Should include both the vent and the ridge cap shingles over it. If your roof currently has a ridge vent, the new one should too. If it doesn't, ask why.
Red flags in a quote
- •A single lump sum with no breakdown
- •No mention of ice-and-water shield
- •"Overlay" instead of "tear-off" (layering over old shingles is cheaper but hides problems)
- •No mention of drip edge or flashing
- •"Materials TBD" or no shingle brand specified
- •No warranty terms listed
How to compare fairly
Line up the quotes item by item. The cheapest quote often skips something the mid-price quote includes. A $2,000 difference might be the ice-and-water shield, the decking allowance, and the drip edge. That's not savings — that's corners cut.