Townhouse and Multi-Unit Slabs

Townhouse development in our area

Medium-density housing is already a significant part of the housing mix in several of the suburbs we service. At the 2021 Census, 24.8 per cent of dwellings in Boronia were semi-detached, terrace or townhouses, and in Knoxfield the figure was 20.4 per cent. In Glen Waverley, much of the housing built on large blocks between the 1950s and 1970s is now ageing, and renewal often involves subdividing those blocks into townhouses. We also quote unit sites in Mulgrave, Wantirna, Noble Park North and Rowville.

The multi-unit concrete package

Dwelling slabs

Each townhouse or unit needs a slab and footings designed by an engineer to AS 2870 and the site classification. Multi-unit sites may have different slab designs across the site because of level changes, fill or trees. We build to the drawings for each dwelling. See house slabs and footings.

Garage and carport slabs

Garages are often integral to the dwelling slab, but detached garages and carports need their own slabs, coordinated with the driveway levels. See garage slabs.

Shared driveways

Common driveways serving several dwellings carry more traffic than a single-house driveway, and they often need to handle drainage for the whole site, including grated drains, pits and connections to the legal point of discharge. Levels have to work for every garage along the driveway.

Vehicle crossovers

Council rules on crossover width, number and position apply to multi-unit sites, and those sites may be assessed differently from single houses. In Greater Dandenong, for example, multi-dwelling sites also need a town planning permit for the crossing. Knox and Monash generally limit residential properties to one crossing, so any additional crossing on a subdivided site needs council approval. See vehicle crossovers.

Paths, bin areas and private open space

Pedestrian paths to each front door, bin storage pads, letterbox areas and courtyard slabs finish the site.

Footpath and asset make-good

Construction traffic on a multi-unit site can damage council footpaths, kerbs and nature strips. Reinstatement is usually a condition before sign-off. See council footpath reinstatement.

Working with builders and developers

On multi-unit projects, reliability matters as much as workmanship. We aim to:

• •work from current engineering and architectural drawings, and query anything that doesn't add up before the pour;
• •coordinate with plumbers, electricians and the building surveyor so inspections happen on time;
• •plan pump and truck access around neighbours, narrow streets and other trades;
• •sequence pours to suit the build program, including staged slabs for dwellings that start at different times.

Common challenges on unit sites

• •Tight access. Narrow sites between existing houses often need boom or line pumps and careful truck scheduling. See concrete pumping.
• •Level changes. Sloping sites may need stepped slabs, retaining walls and ramps. See concrete sleeper retaining walls.
• •Drainage. Stormwater from roofs and hard surfaces must be managed across the site, sometimes with on-site detention conditions in the planning permit.
• •Trees. Retained trees on or near the site can limit excavation and slab design.
• •Neighbours. Shared boundaries mean care with excavation, formwork and pour-day disruption.

Formwork and reinforcement

Every slab on the site depends on accurate formwork and correctly placed steel. We set out forms to the surveyor's pegs and design levels, and place reinforcement to the drawings, ready for inspection. See formwork and steel reinforcement.

What we need to quote a unit site

An accurate quote for a multi-unit package starts with good information. The more of the following you can send, the tighter the quote:

• •engineering drawings for each dwelling slab, plus any retaining or driveway details;
• •the soil report and site classification;
• •architectural site plan showing the driveway, crossovers, paths and bin areas;
• •civil or drainage plans, including pits, grates and any detention system;
• •planning permit conditions that affect concrete, such as crossover positions, tree protection or permeable surfaces;
• •the build program and expected pour sequence.

Where we work

We quote multi-unit concrete packages across Rowville, Boronia, Knoxfield, Glen Waverley, Mulgrave, Wantirna, Dandenong North and the other suburbs on our locations page. See all services for builders on the commercial and formwork hub.