Roof repairs and maintenance

Water shows up a long way from where it gets in. A stain on a bedroom ceiling can start at a chimney counterflashing three metres up the slope, run along a rafter, and drop at the first nail that interrupts the path.

We trace leaks upward from your ceiling stain: checking penetrations first, then valleys and wall junctions, then the roof field, and finally the attic with the lights off. Where access allows, the underside of the deck says more than the top surface does, because a stain there is dated and directional.

We keep to the basics: clean the roof and clear it of debris, trim back overhanging branches, and clear gutters and downspouts of anything that impedes their function. Zinc or copper strips can help control moss growth.

What does not help is pressure. Blasting an asphalt roof strips the granules that protect the asphalt and drives water up under the courses. We remove moss gently and address the shade, airflow, and overhanging limbs that caused it, so the moss does not return.

We recommend inspection at least twice a year, spring and fall, and additionally after severe weather. On this coast the autumn one carries the weight.

A gutter that overflows in November does not stay a gutter problem. Water backs up over the fascia, runs behind the drip edge and gets into the sheathing at the eaves. That is the part of the roof eave protection is meant to cover, and the code does not require it here. Appendix C puts Parksville at 3,200 degree-days, and Article 9.26.5.1 exempts anywhere at 3,500 or fewer.

Clearing gutters, valleys and low-slope outlets before the wet season is the cheapest work on this list by a wide margin.

There is a point where repair stops being economical, and it is usually reached before the covering looks finished. We check whether your deck is sound, whether flashings can be renewed without disturbing shingles, if ventilation hits the code's 1/300 ratio, and how many times the roof was already repaired.

A roof with a sound deck, one failing detail and adequate venting is a repair. A roof with three previous patches, blocked soffits and split sheathing at the valleys is usually a replacement.

We give you a straight answer and explain our reasoning, whether your roof needs a simple repair or a full replacement.

• Leak tracing and diagnosis

  The roof and attic walked to find the entry point.

• Flashing and counterflashing repair

  Chimney, wall and skylight flashings renewed or re-let into the substrate.

• Valley repair

  Open and closed valleys rebuilt where fasteners, membrane or metal have failed.

• Vent boot and stack collar replacement

  Perished rubber collars replaced before they split.

• Moss and debris removal

  Growth removed gently, without pressure, and the conditions that grew it addressed.

• Gutter, downspout and outlet clearing

  Eaves, leaders and low-slope outlets cleared so water leaves the building.

• Sheathing and deck repair

  Localized rot and split sheathing replaced where the surrounding covering is sound.

• Post-storm assessment

  Lifted, cracked or displaced material assessed and reported after severe weather.

Moss is the dominant maintenance issue on this coast, and it is a north-slope and canopy problem rather than a whole-roof one. Growth lifts shingle tabs and holds water against the surface through a winter that BC Building Code Appendix C rates at 1,200 mm of rain for Parksville.

Situation

A two-storey house with a stain appearing on an upstairs ceiling only during prolonged rain, on a covering with roughly half its service life remaining.

Complication

The stain sits two metres downslope of anything obvious. Tracing from inside your attic, we found water entering at a split bathroom vent-boot collar and running along a rafter before dripping from a nail.

Resolution

We replaced the boot and re-laid the surrounding shingles. Nothing else on the roof is touched.