On a newer estate block the question is often not "what can we afford?" but "how much room is left?". That comes down to site cover: the share of your block that can be under a roof. The house, the garage and the patio all count.
The limits by council
- Logan: set by precinct. 60% in small lot areas, 50% in the standard suburban precinct, 40% large suburban, 35% small acreage and 20% (or 700 m²) on acreage.
- Ipswich: council’s building guidelines say 50% for everything with an impervious roof, while City Plan 2025 sets 60% in some areas. Check the figure for your lot with council.
- Redlands: everything with an impervious roof, patio included, up to 50%, and the lot keeps room for two parked cars.
- Brisbane small lots: 50% at 400 to 450 m², 60% at 300 to 400 m², 70% at 200 to 300 m² and 80% at 180 to 200 m². Lots under 180 m² have their own rule since September 2026.
- Gold Coast: limits detached outbuildings by floor area rather than a percentage, starting at 36 m² on lots under 800 m².
Work it out yourself
Take your lot size from your rates notice. Add up the roofed area of the house (including eaves), garage, any existing patio and shed. Subtract that from the limit and you have roughly what is left for a new patio. On a 400 m² lot in Logan’s standard suburban precinct, 50% is 200 m²; if the house and garage already cover 175 m², about 25 m² is left.
If you are over
It is not always the end. A design that goes over can sometimes be approved by council on its merits. We will tell you at the measure-up whether it is worth trying.