Site Coverage and Open Space Requirements in Perth

How much of your block can you actually build on? This is one of the first questions to answer when planning any residential project in Perth. The R-Codes set clear requirements for site coverage and open space.

What is Open Space?

Under the R-Codes, open space is the part of your site not covered by buildings that’s available for residents’ use. This includes:

Gardens and lawns
Driveways and parking areas
Patios and verandahs (if open on two or more sides)
Areas under eaves
Usable flat roof areas

Standard Open Space Requirements

For typical suburban lots in Perth:

R20: Minimum 50% open space
R25: Minimum 50% open space
R30: Minimum 45% open space
R40: Minimum 45% open space

Heritage and Character Areas

Some areas have stricter requirements. For example, Fremantle’s heritage character areas may require:

70% open space as deemed-to-comply
Minimum 60% with design principles justification
At least 50% of open space must be permeable

Deep Soil Areas

Many local planning policies now require deep soil zones for tree planting. Typical requirements include:

Minimum 6 metre dimension
10% of site area
Capable of supporting large tree growth

Maximising Your Site

Understanding these requirements early allows you to design efficiently. Strategies include:

Incorporating covered outdoor living that counts as open space
Using permeable paving for driveways
Designing courtyards that serve multiple functions

Site Analysis

Before you start designing, know your site’s potential. Get in touch for a feasibility assessment.

Disclaimer: This article is provided for general information purposes only. Requirements and regulations may change, and specific circumstances vary. Always consult current legislation, your local council, and qualified professionals before making decisions about your project.