Is one missing shingle a big deal?

In Greater Victoria a single lost shingle is usually a wind story. The exposed south-east and south-west slopes along Dallas Road, in Cadboro Bay and on the Sidney and Sooke waterfronts lose tabs in the first fall storm, typically at the ridge, the rake edge or a corner where gusts get under the edge. A shingle from the middle of a sheltered north slope in Gordon Head or Broadmead, by contrast, more often means the sealant let go with age or the shingle was never properly nailed, and both invite a closer look.

Colour matching is the local complication. Roofs installed in the 1990s and 2000s in Langford and Colwood used shingle lines that have since been discontinued, and even a current product weathers so that the new piece stands out for a year. On a roof you plan to keep for a decade that is cosmetic; on one you plan to sell, some owners have the roofer take a matching shingle from a hidden slope and put the new one there. Ask about it before the visit.

The underlayment under the gap keeps water out for a while, but sun breaks it down and wind works at the now-loose edge of the shingle above. The usual sequence is: one shingle in October, three by December, a damp spot on the ceiling by February. Water that gets past the underlayment wets the sheathing, and on the plank-sheathed roofs of older Victoria homes that is where rot starts. A repair before the wet season costs a fraction of a decking patch after it.

The roofer lifts the shingles above the gap, removes the old nails, slides in a matching shingle, nails it in the right zone and hand-seals the tabs with roofing cement because the factory sealant needs summer heat to bond. On a steep roof or one with eaves over 3 m the crew uses fall protection, which is part of why the minimum visit is $350 to $500 in our model. Do not climb up to do it yourself; a slip on wet or mossy shingles is the most common roof injury in a coastal winter.

• Matching shingle from stock or a hidden slope
• Nails in the nail zone, not exposed
• Hand-sealed tabs in cool weather
• Quick check of the ridge caps and the rest of the slope while up there

If the shingle came from a sheltered spot, if it is brittle and cracked rather than intact, if there are granules in the gutters or curling edges on the slope, or if the roof is past 15 to 20 years, the loss may indicate that the whole slope is losing its seal. That is when a $150 to $400 inspection makes sense; it tells you whether you are buying a few more years with small repairs or whether the next storm will take the decision out of your hands.