Aluminium Window Repair in Dunedin – Hardware, Seals & Drainage on Aluminium Joinery

Aluminium takes two kinds of punishment here. On the coast, from St Clair round to Brighton and up the harbour to Port Chalmers, salt gets under the powder coat and works on the hardware first. Inland, the enemy is age plus a coating that has never been washed, and a frame that conducts cold straight into the room on the fifty odd frost mornings the city gets each year.

Friction stays fail first

The stay is the hinged arm that carries an awning or casement sash and holds it open. They corrode, the pivots seize, and eventually an arm bends or snaps. Once a stay has gone, the sash either will not hold position or drops and fouls the frame.

Replacements are stocked in common sizes and the swap takes minutes per window. Within reach of the water we fit 316 marine grade stainless as standard, because ordinary stays pit within a few years on the south coast.

Re rubbering, the cheapest warmth available

The glazing wedge and the weather seal in an aluminium window are rubber, and rubber hardens, shrinks and takes a permanent set. Once that has happened the sash no longer compresses against anything, so cold air moves through and driven rain follows it.

Re rubbering pulls the old wedge out and rolls new gasket in. It costs less than anything else on this website and in a cold city it changes how a room feels more than most people expect. On a sound 1990s home it is the first thing worth doing.

Corrosion, powder coat and what can be saved

White chalky bloom on a frame is aluminium oxide, which means the coating has been breached. Caught early, a wash and a restorative polish made for powder coat brings the finish back. Left long enough the metal pits and the only fix is a new frame.

Coastal joinery here needs washing with mild detergent every three months, not every six, and never with solvents, bleach or an abrasive pad. Anodised finishes hold up better in salt air than powder coat, which is worth knowing before you order replacements.

Drainage slots and the puddle on your sill

Aluminium windows are designed to let a little water in and drain it back out through slots in the bottom of the frame. Block those with dirt, paint or dead insects and the water backs up over the internal sill and runs down the wall.

A good share of the leaking window callouts we attend turn out to be blocked drainage rather than failed seals. Clearing them takes minutes. Working out that is what is wrong is the part people pay us for.

How Window and Glass Repair Dunedin diagnoses and repairs in Dunedin

Guessing at a cause is how people pay twice. Window and Glass Repair Dunedin finds the fault before quoting the fix, which sometimes means saying the problem is not the window at all.

1. Inspect the opening as one system

   Frame, sashes, hardware, seals and drainage all get checked together, because a fault in any of them presents identically from inside. Looking only at the obvious part is how the wrong repair gets sold.

2. Separate condensation from water ingress

   In a Dunedin winter this is the single most common diagnostic question. Water on the inside face of the glass, pooling on the sill, worse in the morning and worse in bedrooms, is almost always condensation. Water appearing after rain and tracking from the head is not.

3. Water test where ingress is real

   Controlled water on one zone at a time from the bottom up, with somebody watching inside. It takes an hour and it is the only reliable way to find an entry point rather than resealing everything and hoping.

4. Check the drainage before condemning a seal

   Aluminium frames let water in by design and drain it back out through weep holes in the sill. Blocked weeps present exactly like a failed gasket. Clearing them costs almost nothing, so it gets ruled out first.

5. Report the cause in writing

   You get told what failed, why, and whether it will recur. Where the cause is a head flashing, the cladding above or the way the room is ventilated, Window and Glass Repair Dunedin says so rather than quoting glazing work that cannot fix it.

6. Quote repair against replacement

   Where both are genuine options they go on the same quote with the reasoning. Most windows Window and Glass Repair Dunedin is called to do not need replacing, and you should be able to see the gap between the two numbers yourself.

7. Test again before leaving

   Every sash opened, closed, locked and checked for even seal compression. On a leak repair the opening is water tested a second time to confirm the fix.

Why aluminium window repair in Dunedin is its own problem

The housing stock and the climate here combine in a way that produces faults you do not see in warmer cities.

Old joinery that has already moved

A house that has stood since the 1890s has settled, and the openings have gone out of square with it. A sash that will not latch is very often a dropped or racked opening rather than a failed lock, and adjusting is far cheaper than replacing.

Student and rental housing gets harder use

A large share of the older stock is tenanted, which means more cycles on the hardware and more forced sashes. MBIE inspected fifty three Dunedin student rentals in May and June 2026, which gives some sense of how much attention this housing is getting.

Frost and damp accelerate everything

Around fifty ground frost days a year, and a lot of the older stock heated intermittently. Repeated wetting and freezing at the bottom rail is what turns a small paint crack into a rotten sill within a few seasons.

South Dunedin ground is a factor

On the flat, the water table sits close to the surface and moisture frequently rises from the ground rather than condensing from the air. Window and Glass Repair Dunedin checks that before quoting glass that would not fix it.

What aluminium window repair costs in Dunedin

Repair pricing looks unpredictable from outside because it depends entirely on what is actually wrong. These are the bands we quote within.

Diagnosis and call out

A standard assessment covers inspecting the opening as a system and giving you a written cause. Where water ingress is suspected, a controlled water test takes about an hour and is the only reliable way to find an entry point rather than resealing everything and hoping.

Hardware and seals

The cheapest end of this trade. Stays, rollers, catches, handles and gaskets are consumables and replacing them is a fraction of what people expect. Most windows Window and Glass Repair Dunedin is called to do not need replacing and the repair typically sits well under a tenth of a new unit.

Glass and sealed units

A broken pane runs $250 to $600 in a common size. A failed double glazed unit replaced in the existing frame runs $350 to $800. In both cases the frame and hardware stay, which is why repair usually wins on a sound window.

When replacement is the honest answer

Corrosion through the section, a frame distorted by building movement, or where the reason for the job is thermal performance rather than a fault. At that point a repair is money spent on a window you will replace anyway, and Window and Glass Repair Dunedin says so.

Repair or replace: how to decide in Dunedin

Four questions that settle it, in the order worth asking them.

Is the frame itself sound

Aluminium frames usually outlive everything attached to them, and timber frames are repairable far more often than they are replaced. If the frame is sound, almost everything else is a consumable and repair is the clear answer.

Is the complaint a fault, or is it the climate

Condensation running down the inside of the glass on a frost morning is not a fault. No repair fixes it and no reglaze fixes it. Ventilation, heating and thermal performance do, which is a different job with a different budget.

What is the whole of life number

A cheap repair on a window you will replace in three years costs the money twice. A repair on a window with twenty years left is the best value work in this trade. Window and Glass Repair Dunedin puts both numbers on the same quote so the gap is visible.

Is the house being sold or tenanted

On a rental, compliance and durability change the calculation, because the window has to keep working through harder use. On a house being sold, a documented repair is often enough and a full replacement rarely returns its cost.

Common aluminium window faults in Dunedin

Aluminium joinery rarely fails as a frame. It fails at the parts that move and the parts that seal, and both are replaceable.

Hardware wears before anything else

Friction stays, rollers, catches and handles are consumables on a forty year old window. They are also the cheapest thing on the window to replace, which is why most aluminium windows we are called to do not need replacing.

Seals perish and let water in

The wedge gasket and the weather seals harden and shrink with UV exposure. A window that leaks or whistles is usually a seal problem rather than a glass or frame problem.

Drainage holes block

Aluminium frames are designed to let water in and drain it back out through weep holes in the sill. Blocked weeps turn the sill into a tray and that water eventually finds the inside. Clearing them is a five minute job that prevents a large one.

Repair or replace aluminium joinery in Dunedin

The frame itself usually outlives everything attached to it, so the decision is rarely about the aluminium.

When repair is clearly right

Sound frame, square opening, working drainage, and a fault in the hardware or the seals. That describes most of what we attend and it is a fraction of replacement cost.

When replacement makes sense

Corrosion through the section, a frame distorted by building movement, or where the reason for the job is thermal performance rather than a fault. Standard aluminium conducts heat and no repair changes that.

Matching old profiles

Joinery systems change and some older profiles are no longer made. We can usually source compatible hardware or adapt, and where we cannot we will tell you rather than fitting something that almost fits.

Aluminium Window Repair at a glance

Hardware

Friction stays, catches, handles, restrictors, rollers, wind stays

Coastal spec

316 marine grade stainless within about 500m of the water

Seals

Glazing wedge and weather seal replaced in place on most windows

Frames

Corrosion assessed, powder coat restored where the metal is sound

Drainage

Slots cleared and tested with water

Suites

APL, Vantage, First Windows, Altherm, Fairview and older profiles

Maintenance

Wash every 3 months coastal, 6 months inland, mild detergent only