Crown Roofers Sydney roofing company logo
New Zincalume corrugated metal roof installation Crown Roofers Randwick Sydney Eastern Suburbs project 2 — photo 1

Crown Roofers Sydney

Whirlybirds & Roof Ventilation Sydney

Roof ventilation sized and positioned properly — one vent per 50 m² of roof, high, with matching intake at the eaves.

NSW Lic. 471250C$20M Insured10-Year GuaranteeFree Quote

Why Choose Us

Whirlybirds & Roof Ventilation You Can Trust

Sized to the roof

One vent per 50 m², not a number picked at random.

Intake as well as exhaust

Vents without eave intake achieve very little.

Honest assessment

If what you have is working, we say so.

Warning Signs

Signs You Need Whirlybirds & Roof Ventilation

Don't ignore these warning signs — small issues left untreated almost always turn into costly repairs. If you notice any of the following, contact us for a free inspection.

A roof cavity that is stifling in summer
Upstairs rooms that stay hot long after sunset
Condensation or mould appearing on ceilings
Existing whirlybirds that never seem to turn

An unventilated Sydney roof cavity gets extraordinarily hot. In the west it will sit at 60-70°C through a February afternoon, which cooks the ceiling insulation, pushes heat down into the rooms below and drives your cooling costs up. In winter the same cavity traps moisture, and that is where ceiling mould starts.

Ventilation fixes both, but only if it is sized and placed correctly. The rule we work to is one whirlybird or ridge vent per 50 m² of roof area, positioned high on the ridge with matching intake at the eaves — air has to come in somewhere for anything to leave. Undersized or badly positioned units are the most common thing we find already installed.

If your existing setup is adequate, we will tell you that rather than sell you more of them.

All work is carried out under NSW Building Licence 471250C, covered by $20M public liability and backed by our 10-year workmanship guarantee.

Common Questions

Whirlybirds & Roof Ventilation FAQs

How many whirlybirds do I need?

Roughly one per 50 m² of roof area. Two units on a large roof with no eave intake will underperform badly, which is a very common setup.

Do whirlybirds actually work?

Correctly sized and placed with adequate intake, yes, measurably. Undersized or without intake, they largely spin without moving much air.

Will it leak?

Not when flashed properly — the flashing is the part that matters, as with any roof penetration.

Google Reviews

What Our Customers Say

Available across Sydney

Whirlybirds & Roof Ventilation in your suburb

We service every suburb across Greater Sydney. Pick your area below for whirlybirds & roof ventilation pricing, availability, and photos of recent work nearby.

Western Sydney

Northern Beaches

South West Sydney

South Sydney

North Shore

Inner West

Hills District

Eastern Suburbs

Get Started Today

Free Quote for Whirlybirds & Roof Ventilation in Sydney

Get a free, no-obligation site inspection and written quote from our licensed team. We cover all of Greater Sydney and respond within 2 hours.

Free written quote — no pressure
Licensed NSW roof plumbers
Same-day response guaranteed
10-year workmanship guarantee

🔒 Your details are safe. We never share or sell your information.

🔧 Need a Roofer?
Call 0490 688 332