Wood-aluminium windows for coastal Australia
A wood-aluminium window gives the Australian coastal project both halves of the brief in one profile: solid thermally modified timber on the inside — ash, oak or pine — and a weatherproof aluminium cladding outside, structurally bonded into a single section. WA-70 carries that build to a 1,600 × 2,200 mm sash, with the salt-fog hardware schedule, the AS 1170.2 wind-zone configuration and the low-U triple-IGU thermal case the NCC energy line asks for.
One profile, two materials, a structural bond
The timber and the aluminium are bonded into one section, not taped or clipped together as two skins. That distinction is what the coast tests: the bond line is sealed, so the salt air never reaches the timber, and the timber never sees the UV. The aluminium face takes the powder-coat schedule — any RAL, two coats, with the salt-spray hours the coastal specification sets — while the interior is a stain on thermally modified timber, modified for the dimensional stability a coastal humidity cycle demands.
Exterior RAL and interior stain are specified independently, per project. The elevation argument stays simple — the architect names the outside colour and the inside finish as two lines on the schedule, and the factory holds both to the same chip.
What the coastal schedule adds
Salt-fog hardware is standard, not an option, on the Australian coastal line: the fixings and the multi-point engagement carry the salt-fog rating that matches the coating schedule. The wind case follows AS 1170.2 — the site wind zone (N1 through N4) and the exposure class set the structural specification, and where the position sits in the impact region the glazing takes the AS 2208 logic on the same frame. The document pack is coordinated with NATA-accredited laboratories, and the test report and certificate ship with the first container.
Energy, and the acoustic upgrade
The platform is triple-IGU compatible, which is where the low-U build lives for the energy line — the bonded section takes the deeper glazing pocket without widening the visible face. The acoustic case is already certified on the family: the WA-70 ACOUSTIC configuration runs the 47 dB laminated IGU to the Rw 45 dB build, so the street-frontage project gets the timber interior and the noise case from one specification, not two competing systems.
How to write it on the schedule
- Name the species and the modification: thermally modified ash, oak or pine — the interior finish, then the stain line separately from the exterior RAL.
- State the wind zone and exposure class from the site report; the structural case follows, and the impact glazing logic where the position requires it.
- Sash limit to 1,600 × 2,200 mm per leaf; beyond that the drawing splits the opening, which is cheaper than a special frame.
- Budget the lead time at 40–50 days — the timber face works at a different pace than the all-aluminium line, and the schedule should say so.
Questions
Modification stabilises the dimensional movement that a salt-humidity cycle would otherwise push through the bond line — the interior stays quiet through the seasons.