Attic Conversion Cost Calculator
Estimate the cost of converting an attic or roof space into a room in Australia. Choose the conversion type and finish. Headroom, access and structure drive the cost.
Your attic conversion details
Your estimate sits within the typical range.
The two make-or-break factors are headroom and access. If there is not enough height, a dormer or raising the roof is needed, and a compliant staircase has to come from somewhere.
Where the money goes
Estimated breakdown for your configuration
💰 Ways to save
- A simple room conversion where headroom already exists is far cheaper than a dormer or roof raise.
- Get an engineer to assess the structure early, so reinforcement is in the budget, not a surprise.
or from $201/week over 5 years , indicative finance
How we estimate this
An attic conversion in Australia typically costs $15,000 to $120,000 in 2026 depending on the conversion type and structure. A simple room where headroom exists is at the low end; a full dormer with an ensuite reaches the top.
Pricing reviewed: October 2026.
Doing more than just attic conversion?
Build a combined estimate across every part of your project in one place.
Pricing reviewed October 2026. Indicative Australian costs, not a quote.
Understanding attic conversion costs in Australia
An attic conversion in Australia typically costs $15,000 to $120,000 in 2026 depending on the conversion type and structure. A simple room where headroom exists is at the low end; a full dormer with an ensuite reaches the top.
Headroom and access are the make-or-break factors. If the floor cannot carry living loads it needs reinforcing, and a compliant staircase has to be fitted, both common hidden costs.
Frequently asked questions
How much does an attic conversion cost in Australia?
Typically $15,000 to $120,000 in 2026 depending on the conversion type and structure. A simple room is cheapest; a full dormer with an ensuite costs the most.
What makes an attic conversion expensive?
Insufficient headroom (needing a dormer or roof raise), a floor that must be reinforced to carry living loads, and fitting a compliant staircase are the main cost drivers.
Are you a builder / renovation business?
Everyone on this page is working out what attic conversion costs because they are ready to hire. Put your business right beneath the calculator, in your state, so you are who they find. From $50/mo.