What actually wears
A uPVC or aluminium frame is essentially inert. It does not rot, rust or fatigue. Everything that fails on a window over its life is attached to it.
Rollers and carriages. On sliders, the whole sash weight runs on a small contact patch, in a track full of grit. They flat-spot. Replacing them restores the window’s operation entirely.
Hinges and friction stays. They carry the sash and hold it against wind at any opening angle. Worn stays let a sash sag and swing, which is how windows slam and glass breaks.
Multi-point gearboxes. The mechanism inside the sash driving the locking cams. A wear item with a finite number of cycles. When it fails, the handle turns and nothing engages — and because the cams also pull the sash onto its gasket, the window stops sealing at the same moment.
Handles. Mechanically simple, but the most-touched component. Worth having in a finish that will not pit.
Gaskets. Consumables, not parts. They harden under UV and heat and stop compressing.
Corrosion is the local variable
Coastal Mumbai finds the hardware first. Fasteners, hinge pins, exposed springs and gearbox internals all corrode long before the frame or glass show anything.
That makes material and finish grade a genuine specification decision rather than a catalogue preference — particularly on seafront elevations and upper floors, where salt exposure is highest.
Rating hardware to the sash
The single most common hardware failure we are called to is a component that was correct for the original glass and wrong for what replaced it.
Upgrade a single-glazed sash to a sealed unit and the weight increases substantially. If the rollers or hinges are not upgraded at the same time, they fail within a year or two. This applies to glass replacement work as much as to new windows.
Safety hardware
Restrictors. Limit how far a sash opens. Sensible above ground floor and effectively required where small children are present.
Key-locking handles. Prevent a window being opened from inside — useful on accessible ground-floor openings.
Child locks on doors. Particularly on balcony doors, where the alternative is relying on a latch that a toddler can reach.
These are worth specifying at order. Retrofitting is possible but rarely as neat.
Blinds and shading
Internal venetian and roller blinds integrate with the window rather than sitting awkwardly in front of it, and on a west elevation they do useful work reducing glare that glass coatings alone will not.
For shutter-style shading built as part of the window, see designer window shutters.
Finishes
Handles and visible hardware in finishes that suit the frame colour — see colour options for the range we match to.
If something on an existing window has worn, service and repair covers diagnosis and replacement, including on windows we did not supply.