Granny flat / ADU cost estimator
Estimate the likely build cost for a granny flat or secondary dwelling in Perth based on size and finish level, before getting quotes.
This range covers a typical turnkey build; site works, connections and council fees can add to the total.
Compare actual quotes for this projectLocal price context: based on 68 price points from reviews and provider websites across this directory. Recorded prices span jobs of very different sizes, so compare quotes for your exact project.
This is an estimate only; a fixed price requires soil tests and a site inspection.
Enquiries sent through our contact forms may be passed to partner providers, and we may receive a referral fee. Our rankings and scores are based solely on our published scoring method and are not influenced by referral fees.
Get quotes from top-rated renovation contractors
Ranked by our published rubric from recent Google reviews, weighted by relevance to this service (the same order as the category page).
Modus PropertyGet a quote4.9(195) 91
HomeLux RenovationsGet a quote5.0(50) 88
Addstyle Master BuildersGet a quote4.7(61) 84
Hatch RenovationsGet a quote4.8(39) 85
Perth Property ImproverGet a quote5.0(22) 84