The view from your house sets the wind rating
Gladstone is in Wind Region C on the 2011 wind map that the Australian Journal of Emergency Management's 2023 report uses. Inside that region, the Queensland Reconstruction Authority classes each home from C1 to C4 by exposure, from a design site wind speed of 180 km/h at C1 up to 310 km/h at C4.
Hilltop and open sites need a higher class, and the Authority's rule of thumb is simple: the better the view from the house, the higher the wind classification. A garage door looking over the harbour from the hills can need a stronger rating than one in a sheltered street.
Under the NCC 2022 Housing Provisions, a garage door in an opening up to 3 m high on a Region C home must meet AS/NZS 4505. The classification is on your house plans.
Salt, dust and the warranty
Gladstone is a working port. About 50 million tonnes of coal pass through it each year, and the Queensland Alumina refinery at South Trees has run since 1967. Steel-Line recommends washing a Colorbond door at least every six months, and more often in salty or industrial areas.
Read the warranty before you choose a door. Steel-Line's excludes installs within 800 metres of the sea or in an area with industrial fallout, and Gliderol's 7 year curtain corrosion cover does not apply within 800 metres of high salt. Ask which door and finish are covered at your address.
Repairs and new installs
For a repair, the signs are the familiar ones: a door that gets louder, drops fast, will not stay up or feels heavier than it did. A roller door that rolls up loosely or slams shut has lost its balance, Steel-Line says, and resetting it is a professional's job.
For a new door, the door specialist measures the opening, the headroom and the room either side, then checks the wind class and any bushfire rating before quoting.
Around Gladstone
Bushfire overlay
Gladstone Regional Council says a property in a bushfire hazard area on its planning scheme overlay needs a BAL assessment against AS 3959. It also says embers are the most common way houses catch fire, so ask about door seals.
Storm tide zones
The council has six storm tide evacuation zones. In one, ask how high the opener's power point sits.
Heavy rain
Ex-Tropical Cyclone Oswald dropped 819.8 mm on Gladstone in the four days to 28 January 2013. Check the seal along the bottom of the door is whole.
An old storm
A major cyclone hit the town on 2 March 1949 and did extensive damage.
What we would do
If you can see the water from your garage, say so when you send the job. It points to a higher wind class and more salt, and both change which door is the right one.