Duplex Builder

Duplex home usually consists of two attached dwellings separated with a party wall, garages or other spaces. Duplex can be single storey or double storey. The party wall between the two duplexes need to be built in full height from footing to the underside of roof cladding and is required to be fire rated. Because of fire rating requirement, the party wall is usually built in brick or concrete block. If it is to be built in timber construction, special double stud details with fire rated material in between will need to be adopted. The party wall should also be built to achieve required acoustic rating.

Sometimes duplex home is interpreted as two dwellings in the same building enclosure but one on top of the other. In this case, the floor separating the two duplexes needs to be fire rated and acoustically rated. The staircase serving the upper duplex should be separated from the lower duplex in its own fire rated enclosure or open.

When building duplex homes, duplex builder should provide two separate sets of water supply pipes, waste water pipes, underground drainage pipes, electrical cables and gas pipes. Duplex builder also needs to install separate connection and meters of the above services. Stormwater pipes can be joined up before connection to the street gutter. However, councils usually require stormwater detention system to be installed on site before connection to street gutter.

If an existing house is to be modified to become a pair of duplexes, the duplex builder will need to assess if the existing structure and building services can be altered to accomodate fire rated party wall, or fire rated floor, separate water supply, separate electrical cabling, and separate gas service. AAPAC DESIGNBUILD is an experienced duplex builder in Sydney and has completed many duplexes, dual occupancies and attached homes projects.