Aluminum Siding Repair in BC: Dents, Chalking, Paint and the Replacement Question

Aluminum siding is the tough old veteran of Lower Mainland exteriors. Hung on thousands of local homes from the 1960s through the 1980s, it refuses to rot, shrugs off insects, and survives our wet winters better than the wood it replaced. Its weaknesses are cosmetic and specific: it dents, its colour coat chalks and wears through, and its profiles vanished from the market a generation ago. That combination makes aluminum repair its own discipline, covered here as part of our complete siding repair guide.

What aluminum gets right, and where it fails

Understanding the repair options starts with what the material actually is: thin aluminum sheet, roll-formed into lap profiles, with a factory-baked enamel colour coat. The metal is effectively immortal in residential service. Everything that goes wrong is either mechanical or coating-related.

Dents. Hail out in the Fraser Valley, ladders, car doors, kids and pucks: aluminum records every impact. Dents are cosmetic, the waterproofing is unaffected, but they are permanent in a way vinyl's flexible bruises are not.

Chalking. Run a hand over old aluminum and it comes away white. Decades of UV oxidize the enamel into powder that rain streaks down the wall and onto whatever sits below. Chalking is the coating announcing retirement.

Wear-through and scratches. At high-touch spots, around doors, gates, hose bibs, the colour coat wears to bare silver metal. Bare aluminum will not rust like steel, but it oxidizes dull grey and looks exactly as neglected as it is.

Loose and rattling panels. Fasteners work loose over fifty years, and wind gets under panels the way it does with vinyl, though aluminum's stiffness makes it less flighty. Refastening is straightforward and worth doing before a storm turns a rattle into a missing panel.

Pitting and corrosion. Rare, but coastal salt exposure near the water and contact with dissimilar metals (copper pipes, steel fasteners) can pit aluminum. Isolated pitting is cosmetic; galvanic corrosion at contact points needs the contact fixed, not just the panel.

What you will not find: rot, insect damage, or moisture wicking. Aluminum's failure list is short, which is exactly why so much of it is still on walls after half a century, and why the repair-versus-replace decision leans differently than it does for wood or vinyl.

Repairing dents and damaged panels

Aluminum lap panels interlock like vinyl and can be unlocked and replaced individually, the mechanics of the repair are easy. The supply is the problem. Residential aluminum siding effectively left the new-product market decades ago, so replacement lengths come from three places: salvage and reclamation suppliers, who stock orphaned profiles exactly for this; your own house, harvesting panels from a garage flank or other hidden elevation and putting the near-match there instead; or a compatible modern profile, accepted as visibly different and used where the eye forgives.

For small dents on visible walls, there is also the body-shop route, careful pulling and filling, but aluminum creases hold memory, and in low evening light a worked dent usually still ghosts. We are honest about that in assessments: sometimes the right repair for a minor dent is none.

Where impact damage is broad, hail across a whole elevation is the classic case, and insurance is involved, the matching problem becomes central to the claim scope. As with vinyl storm damage, document everything immediately and get an assessment before settling, because "repair the damaged panels" and "achieve a uniform wall" can be very different scopes, and our storm damage guidance applies in full.

The repaint: aluminum's secret second life

Here is the genuinely good news in this guide: aluminum is the most repaintable siding ever hung on houses, and a disciplined repaint is transformative. Unlike vinyl, where dark repaints risk heat warping, rigid aluminum takes any colour. Unlike wood, there is no substrate decay under the failing finish. The metal is a stable, dimensionally boring canvas.

The discipline is all in preparation, and skipping it is why aluminum repaints get a bad name:

1. Wash off every trace of chalk. TSP-substitute or dedicated cleaner, soft brushing, full rinse. Paint bonded to powder peels in sheets.
2. Degloss and spot-treat. Remaining sheen gets scuffed; bare-metal areas get cleaned of oxidation.
3. Prime for metal. Self-etching or bonding primer formulated for aluminum, not a general-purpose wall primer.
4. Topcoat with quality 100 percent acrylic exterior paint, two coats, sprayed and back-rolled for enamel-like evenness on the smooth surface.

Done to that standard, a repainted aluminum wall in our climate holds ten to fifteen years, and the house reads as re-sided from the street. Add correctly colour-matched soffit and fascia work, and the roofline stops giving away the house's age. A repaint also resets the matching problem for future small repairs, everything becomes the new colour, and salvage panels can be painted to match before install.

The repaint path suits homes where the panels are straight and tight, the budget favours preservation, or the owner simply likes the slim shadow lines of the old profiles, they are genuinely handsome, and mid-century houses in Burnaby and New Westminster wear them correctly.

When replacement wins

Aluminum earns replacement in a few situations. Widespread denting on the visible elevations, hail is the usual author, where panel-hunting exceeds re-siding sense. Multiple wear-throughs and prior bad repaints layered into a texture no new coat can hide. A wall assembly that predates modern moisture practice and shows symptoms, because behind that 1970s aluminum there is typically original building paper and zero drainage cavity, and if water is finding the sheathing, the cladding conversation is over; the rainscreen conversation has begun. And finally, the simple aesthetic decision: you are renovating, and the exterior should match the ambition.

Replacement options from aluminum start with modern vinyl, the economical path, no future painting, better impact flexibility than its ancestors, and step up to James Hardie fiber cement, which keeps aluminum's indifference to rot and fire and adds mass, deep profiles and factory colour that flatters any era of house. The full comparison lives in our Hardie versus vinyl guide. Either way, replacement is the once-in-fifty-years moment to rebuild what is behind: weather barrier, flashing, drainage cavity, and, on older homes, exterior insulation while the wall is open, upgrades that programs listed at Better Homes BC may help fund.

Identifying what is actually on your walls

Before any repair conversation, it helps to know your product, and with aluminum, the house rarely comes with paperwork. Three quick field tests tell you most of what matters. The magnet test: a fridge magnet clings to steel siding and ignores aluminum; some Lower Mainland homes wear steel from the same era and its repair story includes rust, which changes the diagnosis. The press test: aluminum flexes under a firm thumb and may hold a small dent; vinyl flexes and springs back; wood does not flex at all. Painted-over walls fool people constantly. The profile read: measure the exposure (the visible height of each course) and note the texture, smooth versus wood-embossed, and the bottom edge shape. Photograph a close-up with a tape measure in frame; that photo is what a salvage supplier needs to hunt a match, and it is the first thing we ask for when someone emails about a dented panel.

While you are close to the wall, look at the fastener heads. Original aluminum installs used aluminum nails; past repairs with steel screws will show rust bleed and mark exactly where a previous owner's handyman stopped caring about galvanic pairs.

The galvanic detail worth two minutes

Aluminum has one chemical enemy on a house: direct contact with more noble metals in the presence of water, which around here means most of the year. Copper is the classic offender, a copper pipe strapped against aluminum siding, runoff from copper flashing or an old copper-treated roof draining down an aluminum wall, and untreated steel fasteners are the everyday one. The aluminum sacrifices itself quietly at the contact point: white crusty corrosion, then pitting, then holes, in that order over years.

The repair is never just the panel. Break the contact, isolate with appropriate barriers or replace the offending fastener with compatible hardware, redirect the runoff, and then replace the damaged aluminum. We check for these pairings on every aluminum assessment because finding one explains a mystery hole faster than any amount of staring at the panel itself.

The repaint, specified

Since the repaint is aluminum's best trick, here is the specification in full, the version worth holding any painter to. Wash with a dedicated cleaner or TSP-substitute until a white rag wiped on the wall comes away clean, then rinse completely and let the wall dry. Scuff remaining gloss with a fine abrasive pad. Treat bare-metal spots: light abrasion, clean, and a self-etching primer designed for aluminum. Prime any chalky-prone areas fully, on badly chalked walls, prime everything, with a bonding primer stated by its manufacturer to be compatible with aluminum. Topcoat twice with a premium 100 percent acrylic exterior paint, sprayed and back-rolled; brush-only application reads as brush marks on smooth metal forever. Mid-tones outperform extremes: very dark colours push thermal movement and show the next generation of chalking sooner, and the fade dynamics we describe in our Hardie colour guide apply to painted metal too. Respect the weather window, warm, dry, and not in direct hot sun, which in practice means a Lower Mainland repaint books between May and early October.

That specification is the difference between the ten-plus-year repaint and the three-year peeling embarrassment, and the difference is entirely in the first three steps.

Aluminum on stratas and rental buildings

A surprising amount of the Lower Mainland's aluminum lives on low-rise rental apartments and older townhome complexes, and at that scale its repair math shifts again. In favour of preservation: the material's indifference to rot means a straight, tight aluminum skin on a forty-year-old building is often genuinely sound, and a building-wide repaint delivers a dramatic refresh at a fraction of recladding cost, attractive to councils managing contingency funds. Against preservation: matching stock across a large complex is harder than across a house, decades of one-off repairs have usually left a patchwork already, and if the building envelope behind the aluminum predates modern practice, a depreciation report or envelope consultant may steer the conversation toward the assembly rather than the finish, territory our building envelope restoration guide covers in full.

The practical middle road we see work: repaint and refasten the building now, done to the specification above, while the council plans and funds the eventual recladding as a scheduled project rather than an emergency. Aluminum is the rare cladding gracious enough to allow that kind of planning, and a council that documents the paint system used buys itself easy touch-up matching for the decade in between.

Living with aluminum: the maintenance short list

For owners keeping their aluminum long-term, the list is mercifully brief. Wash annually, a hose and soft brush, both for looks and to slow chalking. Keep sprinklers off the walls; constant mineral-rich spray accelerates coating wear in one streaky patch. Check fasteners and bottom edges each fall before wind season. Touch up bare-metal scratches with primer and matched paint before oxidation spreads the dull patch. And when something dents or loosens, deal with it while it is one panel's worth of problem.

It is worth saying plainly, because so much siding marketing implies otherwise: healthy aluminum is not a problem to be solved. It is a serviceable, honest cladding that has already outlasted two generations of trends, and the right move for a straight, tight aluminum wall is often stewardship, not sales. Where it has aged out, the modern options are genuinely better. Where it has not, we will happily tune it up and shake your hand.

If your aluminum-clad home needs a verdict, repairable, repaintable, or ready for its next fifty years in a new skin, book a free assessment or call 778-358-2885. We will give you the honest version, including when the honest version is "wash it and leave it alone."