Building: 31 dwellings: 11 single storey Class 1a and 20 Class 2 dwellings in two storey buildings, Type C construction
Location: Regional Victoria, north of Melbourne
NCC edition: NCC 2022, Volume One and Housing Provisions
Area of NCC requirements: F3P1 weatherproofing (AS 3700 weepholes and DPC, AS 2870 ground fall); D1P1 access (D4D2, D4D3, D4D4, AS 1428.1 clause 10)
Raised by: The relevant building surveyor, after the building permit was issued
Year: 2026
The challenge
The site falls about 6 metres from the street to a creek reserve at the rear. To give each dwelling a step free entry and a usable accessible path, finished ground was raised close to floor level at some porches and paths. That squeezed three things the Deemed to Satisfy rules expect: the clearance below weepholes and the damp proof course, the 1:20 fall of ground away from the slab over the first metre, and the 1:14 maximum gradient on accessways.
The performance solution
One report covered all three departures, because they shared one cause. Each was assessed against the Performance Requirement using expert judgement and comparison with the Deemed to Satisfy Provisions.
Weepholes and DPC. Reduced clearance was limited to a few entry porches. Those walls use a drained, vented AAC or fibre cement cladding system over a vapour permeable membrane. The ground at each one is paved and often under a porch roof, which removes the mulch and soil build up the clearance is meant to guard against.
Ground fall. Tight side setbacks left less than a metre for the full fall in places. The report relied on engineered pavement falling to grated pits, subsoil drainage behind retaining walls and slab on ground construction, with no reverse grading allowed anywhere.
Accessway gradient. Most entries met 1:14. For the one short section that could not, the report capped the gradient at 1:10 per run with 1200 mm landings, P4 slip resistant paving, path lighting, and resident information showing the flattest route and visitor parking.
Conditions
Photo records of each DPC before paving, an annual maintenance inspection, and a rule that later paving or landscaping must not reduce the clearance or fall. All of this is recorded on the occupancy permit for the owners corporation.
Outcome
Final report issued in July 2026 and successfully accepted by the relevant building surveyor.
Lesson for designers
On a sloping site, decide entry levels, accessible paths and DPC heights together at design stage. Dealt with one at a time, each fix creates the next departure.
Related: Performance solution report | Performance solutions Victoria
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