What's the right way to flash a dormer window on a heritage home in Fredericton's Waterloo Row area?

Flashing a dormer window on a heritage home requires careful attention to both weatherproofing and heritage preservation standards. Waterloo Row properties fall under Fredericton's Heritage Conservation Area, so you'll need heritage approval before making any exterior changes visible from the street.

Start by contacting the City of Fredericton's Heritage Officer at (506) 460-2020 before beginning work. Even window flashing modifications may require heritage approval if they alter the building's appearance or involve removing original materials. The Heritage Conservation Act (SNB 2009, c H-4.05) protects these properties, and unauthorized changes can result in stop-work orders.

For the flashing itself, step flashing is critical where the dormer sidewalls meet the main roof. Install individual pieces of step flashing (typically 6" x 8" aluminum or copper) under each course of shingles, with each piece overlapping the one below by at least 2 inches. The flashing should extend at least 4 inches up the dormer wall and 4 inches onto the roof deck. Use copper flashing if the heritage guidelines require it - many Waterloo Row homes have copper gutters and downspouts that should be matched.

Head flashing above the window needs particular attention on these older homes. Install a continuous piece that extends under the siding and over the window head casing, with proper kickout details at each end. The flashing should have a minimum 1/4" drip edge. On heritage homes, you may need to carefully remove original clapboard siding to properly install the flashing, then reinstall it exactly as it was.

Given New Brunswick's freeze-thaw cycles and heavy snow loads, seal all flashing joints with high-quality polyurethane sealant rated for exterior use. The dormer's location makes it vulnerable to ice damming, so ensure adequate attic ventilation and consider ice and water shield membrane under the first three courses of shingles.

Professional installation is strongly recommended for heritage properties. A roofing contractor experienced with heritage work will understand both the technical requirements and heritage sensitivities. They'll also carry proper insurance for working on these valuable properties.

Contact Fredericton's Development Services first to confirm heritage requirements, then find a qualified roofer familiar with heritage standards in our contractor directory.