Unit Development

What is a Multi-Unit Development?

What is a multi-unit development? A multi-unit development is when more than one dwelling is built on a single lot of land. This could be made up of houses, units, townhouses or apartments.

Multi unit developments are becoming very common due to population growth in inner-city areas and the ability for the developer to make large profits out of the allotted land.

Unit developments are subject to rules and regulations set out by the local council the land is in, Residential Design Codes (r-codes), Building Codes Of Australia (BCA) and the Australian Standards.

These rules make fitting as many units onto the land as possible an intricate project. Therefore, it is wise to engage in an experienced specialist for advice to help design and construct the project so the investment is worthwhile.

mutli unit development

Unit Development Process

There are a few key steps to follow when creating a multi-unit development to allow the process to go smoothly and give the largest return on investment.

Feasibility and Investigation

The first step when looking into a multi-unit development is checking the feasibility of the project. This includes

  • Checking with the council to know any restriction and the r code of the block
  • Ordering a survey to see the levels and any hidden features
  • Checking the existing retaining
  • Comparing proposed units to recently sold in the area to determine a budget


Designing the project to get the best orientation and layout of multiple units on a lot of land is not a beginner’s task due to the large array of rules and regulation to follow. This is due to cramming as many units as you can in an attractive and functional location while at the same complying with the vast number of regulations to be followed.

Planning Permits

Planning permits and subdivision are needed to build any unit development. This is taken up with the local council, in some cases, a written statement is needed when the design does not fully comply but you have good reasoning and believe it is the best way. This is where experience with local councils really helps as you know what you can get away with.

Several factors that are usually considered when planning the development are:

  • site orientation for passive solar design
  • Shadowing on neighbours’ properties
  • Energy rating of units
  • Space for cars to park
  • Overlooking windows on neighbouring properties
  • The slope of the land


The building stage of a multi-unit development is important to be overseen by a professional. This is due to the amount of costly and timely errors that can happen due to builders taking shortcuts.

Types of multi-unit developments

There are multiple types of multi-unit development projects depending on what is able to be placed on a lot of land.


A duplex is a single residential building with two homes within it according to Build Search. Duplexes are covered in the land title or can have separate titles. Both arrangements work. They usually have the same floorplan but are mirrored.


A bit different to a duplex, a triplex does not usually have the exact same floorplans between the houses. It is used when you have 3 units that are built on the street frontage with one common driveway.


Multi unit developments are usually made up of multiple small single or double-storey houses built around a shared driveway. However, it can also include a house behind house development which is quite common in Perth council areas such as Joondalup and Stirling.

Multi-Unit Development Perth 


A townhouse development is basically the same as a unit. However, they are usually multi-storey to maximise the development potential of the land.


An apartment is a multi-unit development that has multiple dwellings on different levels of the building. These are generally larger-scale projects.

Dealing with a professional for a unit development

A unit development is usually undertaken by an experienced person. Contacting a builder to help is generally not the best way to do it. This is because they are not interested in you getting a return on investment as they are of how much they can earn from you.

Perth Building Broker has many years of experience in unit developments and it is a good idea to call us for a free chat before you sign or talk with a builder.


Don't get tricked by the builders, fix the price before you sign and allow us to watch over and guide you through the process.