The escarpment guide explains why so many Illawarra blocks are steep. This page covers the house form that most often works best on them.
What is a split-level home?
A split-level home has floors set at staggered heights, usually half a storey apart, linked by short flights of stairs. Instead of levelling the block to suit a flat floor plan, the house follows the fall of the land: living areas on one level, bedrooms a half-level up or down, and garaging where the street level allows.
Why build split-level on a sloping block?
- Less excavation: each level sits close to natural ground, so less soil is cut out and carted away.
- Less retaining: smaller cuts mean lower retaining walls, which matter because earthworks and walls over 600 mm fall outside exempt development and need engineering.
- Better drainage: less cut into the hillside means less groundwater to collect and pipe away from the house.
- Views and light: upper half-levels look over lower roofs, which is often the point of buying on the escarpment.
On unstable ground, keeping cuts small can also be what the geotechnical engineer requires: see geotechnical reports for escarpment blocks.
What are the trade-offs?
- Stairs: short flights between every level. Keep a bedroom and bathroom on the entry level if step-free living matters.
- Structure: each change in level needs its own footing design, often a mix of slab and suspended floor.
- Design time: a split-level is designed for one block, not adapted from a standard plan.
The footing choices behind each level are compared in suspended slab, piers or cut and fill.
Does your block suit a split-level home?
| Block | Usually suits |
|---|---|
| Gentle, even fall | Single slab with a small cut, or a two-level split |
| Moderate fall along the depth | Split-level following the fall |
| Steep fall or unstable ground | Split-level or suspended floors on piers, as the geotechnical report directs |
| Cross-fall | Split-level across the width, with careful driveway design |
What does a split-level look like on an Illawarra clifftop?
Wombarra Clifftops, a knockdown rebuild I built on a clifftop slip area close to a main road, is a split-level home designed around complex engineering, stormwater and slope. It won the Contract Homes $1.9 Million to $2 Million category at the Master Builders NSW 2026 Southern Regions Excellence in Building Awards. More escarpment builds are on the projects page.
If your block falls more than a metre or two across the house footprint, ask a builder of split-level homes on Illawarra sloping blocks to sketch the levels before you choose a plan.
Sources
Checked on 25 October 2026.
- NSW Planning Portal, Earthworks, retaining walls and structural supports: exempt development standards.
- Wollongong City Council, DCP 2009 chapter list: E12 Geotechnical Assessment of Slope Instability, E14 Stormwater Management, E16 Bushfire Management, E19 Earthworks.
- Master Builders Association of NSW, 2026 Southern Regions Excellence in Building Awards winners: Wombarra Clifftops, Contract Homes $1.9 Million to $2 Million.
- Illawarra Mercury, Wombarra: Luxury clifftop home conquers challenging escarpment site, 27 August 2026.
General information from a builder, not engineering or planning advice. Your geotechnical engineer, structural engineer and certifier decide what your site needs.