The steepest suburbs in Greater Brisbane

Slope is the constraint that quietly sets the cost of a Greater Brisbane block. It decides whether a slab sits on the ground or on piers, whether the driveway needs a retaining wall, and how much soil leaves the site before anything is built. It is also the one site characteristic almost never published per suburb, so this page ranks it.

The extremes and the norm sit in different places. 8 of the ten steepest suburbs are in Moreton Bay City, up on the range and the ridges behind it. But the steepest typical suburb belongs to Brisbane City, whose middle suburb runs at 6.2% against 3.1% for Redland City. A council that pairs a mountain edge with a wide coastal plain collects the dramatic entries and still has a flat middle; a council whose hills run right through its established inner and western suburbs has the steeper middle. If you are buying on the odds rather than sightseeing, the second column of the council table is the one that matters.

The 30 steepest suburbs

"Steep lots" counts the share of measured address points in the suburb where the slope is 15% or more, which is roughly the grade at which a conventional slab-on-ground stops being the obvious answer.

The 15 flattest suburbs

The other end of the same ranking, so the rank column counts down from 384. These are the river flats, the reclaimed industrial land and the bay-side sand plains. Flat is not automatically the easier build: several of these suburbs trade a slope problem for a flood or a soft-ground one.

By council

Each figure below is the median of that council's ranked suburb medians - a middle suburb, not a middle address. It answers "what is a typical suburb in this council like", which is a different question from "what is a typical block in this council like", and the two do not have to agree.

What this page does not tell you

• It is not a figure for your block. A suburb median says what is typical, and half the addresses in every suburb listed are steeper than its number. A flat block in a steep suburb and a steep block in a flat one are both ordinary.
• It counts addresses, not titles. Where several addresses share one lot, that lot contributes several points, so suburbs with multi-dwelling development carry slightly more weight per parcel.
• It is Queensland only, on purpose. LayeredGeo measures lot-level slope in the councils its lot-risk build covers, and that coverage differs by state. Ranking suburbs across states on this data would measure where we have measured, not where the ground is steep, so this page does not do it.
• 50 m is the resolution of the question. The grade is measured over a 50 m arm from the address, so it describes the fall across a block and its street, not a batter, a cut or a retaining wall inside the block.

Getting the number for one address

The suburb figure is a screening tool. For a specific address, the Terrain Report measures fall, slope and aspect across the actual lot boundary and prices at $9. The Planning Report covers the constraints that usually travel with slope - steep land and landslide overlays, vegetation, and the flood mapping that matters at the flat end of this list. Suburb-level profiles for every suburb named here sit under Queensland suburb profiles.