Burnaby Roof Flashing: What It Is and Why It Matters

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1. A Climate That Punishes Every Seam

Burnaby’s meteorological profile reads like a stress test for roofs: 1,200 mm of annual rain; freeze-thaw mood swings from -5 °C nights to 10 °C afternoons; mid-winter southeasters that hammer flashing edges at 60 km/h. Where water insists on sneaking in, flashing must stand guard. Without it, capillary creep burrows under shingles, swells plywood, and invites a silent bloom of rot that hollows soffits from the inside out. I’ve peeled back plenty of “mystery leaks” only to discover an absent or mangled Z-flashing behind a stucco wall. Moral of the story? In Burnaby, the flashing is not an accessory; it is the roof’s immune system.

2. Anatomy and Lexicon

• Step flashing —small L-shaped pieces that zig-zag up the shingle courses beside chimneys or dormers.
• Continuous (apron) flashing —a long bend that escorts runoff where low-slope asphalt meets a vertical wall.
• Counter flashing —protective cap that overlaps base flashing, shielding fasteners from UV and splash-back.
• Drip-edge —metal strip at eaves and rakes, forcing water to drip clear of fascia.
• Kick-out flashing —a flared tab that ejects wall water into the gutter, ending the infamous “stucco stain” streaks that plague older Burnaby ranchers.

3. Material Showdown

Material	Typical Gauge	Burnaby Strength	Burnaby Weakness
Copper	16–20 oz	Self-seals at nails, never rusts	Sticker shock
Galvanized Steel	26–28 ga	Impact-resistant, paintable	Edge corrosion if cut bare
Painted Aluminum	0.019–0.024 in	Lightweight, forms tight bends	Dents, prone to galvanic bleed with cedar
Stainless	26 ga	Salt-spray proof for Burrard Inlet sites	Harder to bend on site
PVC Membrane Flashing	60 mil	Welds chemically, great on flat roofs	UV chalking over decades

4. Where Flashing Must Never Fail

1. Chimney Shoulders – Soot plus condensate accelerates acid corrosion; double-layer step flashing is mandatory.
2. Skylight Curbs – A skylight is essentially a hole on purpose; wrap both curb and curb base.
3. Deck-to-Wall Intersections – Keep ledger rot at bay with 45° kick-outs and peel-and-stick underlayments.
4. Valley Terminations – Burnaby’s cedar-leaf debris piles here; hemmed valley flashing prevents back-flow.
5. Parapet Caps – Commercial plazas on Kingsway live or die by these. Loose cap flashing equals soggy drywall inside sushi shops.

5. Crafting the Seal: Installation Nuances

• Hem Every Edge – Folding a ½-inch hem stiffens metal and eliminates razor-sharp drip lines.
• Break a 10° Kick – At rakes and eaves, tilt drip-edge downward to shun wind-driven rain.
• Sequence Matters – Underlay, step flashing, shingle, repeat. Never reverse the sandwich.
• Use Compatible Fasteners – Stainless nails for copper; electro-galvanized for steel; nothing eats aluminum faster than a rogue steel screw.
• Lap With The Weather – Minimum 75 mm overlaps heading downhill. Think salmon swimming upstream; water should never find a tail-gate to ride under.

6. Failure Diagnostics—A Roofer’s Field Notes

• Brown spot on cathedral ceiling, 30 cm below valley?—Likely pin-hole rust in galvanized valley flashing.
• Water behind vinyl siding, lower corner of a gable?—Missing kick-out; runoff pours straight into sheathing.
• Moldy attic sheathing near eave?—Improperly lapped drip-edge allowed ice dams to wick upward.
• Flapping aluminum above a chimney?—Counter flashing not regletted into brick. Freeze-thaw popped the caulk line.

7. Maintenance & Inspection Cadence

• Spring – Post-storm visual sweep, clear debris, check for oil-canning.
• Mid-Summer – Touch-up paint on steel cut edges before UV degrades the coating.
• Autumn – Gutter cleaning paired with binocular check of kick-outs.
• After Heavy Wind Warning – Quick perimeter walk to spot lifted drip-edge before rain follows.

8. Code & Warranty Intersection

• Minimum 26 ga corrosion-protected sheet metal.
• Drip-edge required on all new asphalt roofs, even over under-eave vent panels.
• Parapet cap flashing must project 50 mm each side and slope inward 2%.

Manufacturer warranties also speak: Malarkey’s “Secure Choice” roof system voids coverage if step flashing laps under 75 mm. File that under expensive ignorance.

9. Cost versus Consequence

Scenario	Upfront Flashing Cost	Five-Year Repair Cost	Ten-Year Impact
Proper copper kick-outs	$350	$0	Dry walls, zero mold
Skipped kick-outs	$0	$4,200 stucco repair	Mold remediation, resale discount
Generic steel valley	$180	$0	25-year leak-free valley
Improperly cut valley	$120	$1,800 plywood patch	Repeat repairs every storm cycle

The spreadsheet doesn’t lie: Cheap shortcuts accrue compound interest in rot.

10. DIY or Dial a Pro?

YouTube confidence peaks until you stand twelve feet up, tin snips in numb fingers, Burnaby mist blowing sideways. Ask yourself:

• Do I own a brake or will I hand-bend off a 2×4?
• Can I match the reveal of existing siding?
• Am I prepared to strip back three courses of shingles to resequence flashing?

If more than one “no,” phone a roofer—preferably one who sweats the small metal, not just the big squares.

11. Innovations on the Horizon

• PVC-backed stainless hybrid – Combines weldable membrane skirt with 40-yr stainless cap. Ideal for Burnaby flat-to-wall details.
• Laser-measured prefab kits – Drone captures wall geometry; CNC brake prints step-flashing set with precise reveals.
• Conductive Snow-Melt Flashing – Thin heating ribbon laminated under drip-edge to thwart ice dams without bulky cables.
• Self-repair Coatings – Micro-capsule paint on steel releases rust-inhibitors if scratched.

We trialed the hybrid stainless on a rain-screen retrofit off Royal Oak. Three winters later, the curb flashings still bead water like a lotus leaf.

12. Frequently Asked Questions (Beyond Position 0)

Q: How long should galvanized step flashing last in Burnaby?
A: Installed correctly, 25–30 years; aggressive coastal winds may shave that to 20 near the Inlet.

Q: Can I reuse flashing during a re-roof?
A: Rarely. Nail holes and metal fatigue compromise its integrity—and any manufacturer warranty.

Q: Do cedar roofs need different flashing?
A: Yes, use copper or stainless to avoid acidic runoff eating zinc coatings off steel.

Q: Are caulked joints acceptable?
A: Caulk is Band-Aid, not bone. Use it sparingly to backstop good overlaps, never as the primary seal.

13. Case Study—Metrotown Mid-Rise

A 14-storey strata called with chronic ceiling leaks along units 505 and 1002. Infrared scan traced moisture to balcony slab intersections. Root cause: original builder omitted base flashing behind the stucco cladding; water tracked three floors before manifesting. Solution:

1. Demo 1 m of cladding above slabs.
2. Install 24-ga stainless base flashing with 100 mm vertical leg.
3. Lap torch-on membrane over base.
4. Re-stucco with rainscreen drainage plane.

Leak count since repair: zero, despite 143 mm December downpour (2024).

14. The Human Cost of Water That Won’t Stay Outside

Rot is stealthy, but its outcomes are loud: spongy subfloors, blackened drywall, displaced tenants, insurance premiums skyrocketing. One litre a day of drip equals one cubic metre a year—enough to fill a hot tub beneath your rafters. Flashing costs pennies on that dollar.

15. Closing Thoughts from the Ridge Cap

Some elements of roofing are spectacular—the standing-seam panels glinting at sunset over Deer Lake, the crisp symmetry of architectural shingles—but the unsung hero is the narrow, folded strip of metal that politicks gravity. Flashing is persuasion in sheet form, coaxing water to follow a harmless path. In Burnaby, where rain writes its own schedule, that persuasion must be eloquent.

As roofers at Paragon Roofing BC, we judge our craft not just by how a roof looks on day one, but by how dry the attic smells ten winters later. When we tuck a hemmed piece of copper behind cedar siding or seat a stainless apron atop fresh peel-and-stick, we’re writing insurance policies against storms no meteorologist has named yet.

Invest in flashing. complete roofing systems in Burnaby today is thirty years of silence tomorrow—the rare home upgrade you’ll forget exists because it does its job without complaint. And in a city that measures seasons in millimetres of rain, that silence is golden.