Home Extension Cost in Perth (2026)
Perth extensions are cheap to excavate but dear to tie into double brick, and isolation lifts the material bill.
Your home extension details
Approximate added floor area in square metres.
Your estimate sits within the typical range.
Site access, slope and connecting to existing services can add tens of thousands, get a site assessment early.
Where the money goes
Estimated breakdown for your configuration
💰 Ways to save
- Single-storey on a flat, accessible block is the cheapest way to add space.
- A simpler roofline and standard ceiling heights keep costs down.
or from $566/week over 5 years , indicative finance
How we estimate this
Home extensions in Australia are typically priced per square metre, about $2,400/m² for a basic single-storey addition to $4,500/m²+ for premium or double-storey work in 2026.
Pricing reviewed: June 2026.
What a home extension costs in Perth
Perth's sandy, free-draining soils make excavation and footings quick and cheap, so the groundwork for an extension is among the least expensive in the country. The complication is construction: most Perth housing is single-storey double-brick on slab, and marrying a new structure into a double-brick wall, cutting in openings and matching the masonry, is more involved and more costly than extending a timber-framed home.
As the most isolated capital, Perth prices in freight and lead time on anything specialist, from imported windows and tiles to steel, which an extension's material schedule has to carry. Labour sits near the national average, so a straightforward single-storey addition on a modern slab home stays affordable, while a two-storey addition onto a character double-brick home in the western suburbs runs well above the national figure.
Compare against the national picture: Home Extension Cost in Australia →
Home Extension Cost in other cities
Frequently asked questions
How much does a home extension cost per square metre in Australia?
In 2026, single-storey extensions typically cost $2,400–$3,500/m² and double-storey $3,500–$4,500/m²+, depending on finish and site conditions.
Is it cheaper to extend or move house?
Extending avoids stamp duty, agent fees and moving costs. For many families a well-planned extension adds value above its cost, though this varies by suburb.
Do I need council approval for a home extension?
Most extensions need development approval or a complying development certificate. Requirements vary by state and council, your builder or a private certifier can advise.