How much does tear-off and disposal add to a roof replacement?

Roof area, not floor area, drives tear-off. A 2,000 sq ft two-storey home in Langford's Westhills has about 1,200 sq ft of roof; a 2,000 sq ft rancher in Broadmead or Cordova Bay has nearly 2,400 sq ft. That is why a bungalow's second-layer removal can cost double a two-storey's even though the houses are the same size on paper.

The haul matters too. Core-city and Saanich jobs are a short run to Hartland; Sooke, Metchosin and North Saanich jobs tie up the truck longer and sometimes need a second bin swap. On tight Oak Bay and James Bay lots the bin sits on the street and shingles are carried, which shows up as an access factor (up to 12 percent in our model) rather than a tear-off line, but it is the same work.

Tear-off is labour: prying up shingles, pulling nails, scraping old felt and loading the bin. Disposal is the bin rental, the trucking and the tipping fee by weight. A clean single layer of asphalt from a 1,200 sq ft roof weighs a little over a tonne; a moss-laden double layer can be triple that. Some contractors quote disposal as a fixed line, some fold it into the rate, and a few leave it 'by weight', which is the version to question.

Look at the drip edge from a ladder placed on firm ground, or better, ask the estimator to show you. Layers are visible at the eave as stacked shingle edges. From inside the attic, the pattern of nail points through the sheathing hints at more than one layer. Do not walk the roof to check; a good estimator will photograph the edge for you.

• Stacked edges at the eave or rake
• A roof that looks unusually thick at the gutter line
• Home built before 1985 with no record of a full tear-off
• Cedar visible under asphalt in the attic or at the edge

Have moss treated and brushed off months before the re-roof so the crew is not shovelling wet growth. Clear the driveway so the bin can sit next to the house. Bundle the gutter cleaning or fascia work into the same visit. None of these change the layers you have, but they shorten the crew day, and a shorter day is a smaller bill.