What steam actually does
Every hot shower loads the room's air with moisture, and the window is where it lands: glass and frames are the coldest surfaces in the room, so that is where the air gives its water back. Day after day, condensation sits on sills, wicks into timber, lifts paint at the joints and feeds the grey bloom in the corners. Fabric blinds fare worse, holding the damp and the smell of it. This is not a defect in those products; it is the wrong climate for them.
Why PVC is the honest answer here
Waterproof PVC louvres have nothing in them for moisture to attack: no grain to swell, no paint film to lift, nothing organic for mould to feed on. The morning fog dries off them without a trace, and whatever film builds up over months wipes off with a damp cloth. That is the whole pitch, and it is enough. The detail is on the PVC wet-areas page.
The louvre format itself is doing half the work, and it is worth noticing why:
- Privacy with the light on. Most bathroom windows stare at a fence or a neighbour's wall from close range. Blades tilted up pass daylight and stop the sight-line, so the frosted-film gloom is unnecessary. The same angle logic as street privacy.
- Ventilation through the privacy. A wet room has to exhale. Panels crack open, blades still angled, and the steam vents while the window stays private. A sealed treatment cannot do both at once.
- No cords, no fabric. Nothing to launder, nothing to tangle, nothing for small hands to reach from the bath.
The one limit worth knowing
PVC blades run heavier than timber. On very wide single panels the weight argues for a split, a mid-rail or a step down in blade width, which is why our wet-area work usually lands at 63 or 89 mm blades across sensible panel sizes. It is a set-out constraint, not a quality problem, and it is exactly the sort of call that gets made properly at a measure with a tape on the reveal.
Where else PVC makes sense
Laundries, obviously, where the tub and the dryer make their own fog. Kitchens close to the sink. And, told straight, any hard-working room where budget matters more than the last word in finish: the tilt control and the wipe-down ease are identical, and we quote the mix openly so you can put timber where it shows and PVC where it works. That mixed, room-by-room approach is standard on our quotes around Kurri Kurri and the villages especially.
Choose materials the way the house experiences them: by room, not by brochure page.
If the bathroom is part of a bigger rethink, walk the whole house through the Aspect Planner; pick "bathroom or laundry" and it will steer the wet rooms to PVC by itself, and explain why. Ready for numbers? Book the free measure.