Complex terrain is a design problem, not an excuse to compromise.
Sydney has some of the most constrained residential topography in the country. Split-level homes done well sit calmly on the slope, hold stable internal temperature across levels, and reduce excavation. Done badly they leak energy, crack slabs, and cost twice as much as they should.
Review our split-level workThe three failure modes in Sydney split-level builds.
1. Thermal bridging at every level change
Every floor step is a potential thermal bridge if detailed carelessly. We model the junctions in Therm at design stage and carry the airtightness layer continuously through the step.
2. Retaining-wall and slab interaction
A retaining wall on a sloping site is load-bearing and often waterproofing-critical. Treat it as a separate trade and you get leaks. We integrate it with the structural engineer at concept. For shallow-slope lots we use a different design approach, covered on our wide shallow block designs page.
3. Internal comfort across levels
Warm air rises. Cold air settles. A three-level split-level home without zoned MVHR has uncomfortable corners by design. We zone the ventilation per level.
Four stages, in order.
We will not price a sloping site without a current contour survey and a review of the LEP height, setback, and cut/fill controls.
The structural engineer and our design team agree the step layout together so detailing, insulation, and airtightness are compatible with the slab set-downs.
Retaining walls, slab edges and sub-soil drainage are drawn together and waterproofed as a system.
Each level commissioned separately. MVHR zones balanced and recorded per level.
Frequently asked
- We have built on grades up to 1:4. Above that it is possible but the earthworks and retaining costs start to dominate the budget. We would talk you through it candidly.
Send the contour survey.
The fastest way to get a useful answer on a sloping block is to send us the contour survey and the block title. We will come back in a week.