Roof Ventilation - Whirlybirds, Solar Vents & Ridge Vent

Roof ventilation is the single most undersized item in Australian homes. The standard 'one whirlybird does the job' is wrong - a 300mm Edmonds Twista moves about 100 m³/hr in light wind, but a typical Sydney roof cavity is 200-300 m³ that wants 8-12 air changes an hour to manage heat and condensation. The math says 2-4 whirlybirds or a single proper solar-powered vent like the SolarKing RAF1200.

Ventilation also needs intake to work. A vent on the ridge with no soffit vents below pulls conditioned air out of the house through ceiling penetrations instead of pulling fresh air through eaves. Tradetek's installs always pair high-level extraction (whirlybird, solar vent or continuous ridge vent) with continuous soffit intake or eave vents sized to AS/NZS 4859 - so the air actually circulates.

Product selection comes down to noise, cost and effectiveness. Wind-driven whirlybirds (Edmonds, CSR) are cheap and silent but rely on wind. Solar-powered vents (SolarKing, EcoSwitch) move 5-10x the air and work in still air but cost more. Continuous ridge vent is the architect's choice on new builds and re-roofs - invisible, no noise, no maintenance, and matches ridge cap profile.

Every install includes correct flashing for the roof profile (proper Dektite-style flashings on metal, mortar bed and lead apron on tile), insulation pulled back from the vent to allow free air movement, soffit intake assessment and upgrade where missing, and a workmanship warranty in writing. Most installs are completed in 2-4 hours with no internal access required.