Use this calculator to estimate the cost of your home extension or renovation project, including building works, fixed items, and optional extras.
You can add to list of rooms below as necessary. You can enter the size of rooms you require.
| Item | Area (m²) |
Rate ($/m²) |
Cost ($) |
Note |
|---|---|---|---|---|
| Lower Level Extension | 0 |
Note
Small extension (0–12m²):
Simple @ $6,500/m² Complex @ $7,000/m² Medium extension (13–25m²): Simple @ $5,500/m² Complex @ $6,000/m² Large extension (26–100+m²): Simple @ $5,000/m² Complex @ $5,000/m² See also notes about kitchen, bathroom, or laundry additions increasing the rate. The area allowed for is effectively the area of any work excluding wet areas (kitchens, bathrooms, laundry, etc.). |
||
| Upper Level Extension | 0 |
Note
Use similar rates for lower floor extensions, but note that to do an upper level extension you lose approx. 8m² of floor area on both levels to allow for a stairwell. This is almost the size of a small bedroom and needs to be replaced in the overall area of the house. This additional area needs to be factored into the cost calculation — i.e. there is an opportunity cost to doing an upper level extension. Suggested Rates:
See also comments about kitchen and bathroom adding to the area rate if included as part of the extension. The area allowed for is effectively the area of any work less the wet area allowance (i.e. kitchens, bathrooms, laundry, etc.). |
Please select the items you want to include in your renovation:
| Select | Item | Cost ($) | Note |
|---|
The items listed below do not necessarily relate to the area of the building but obviously have some significant influence on the overall cost and need to be entered seperately. Please select the items you want to include in your renovation:
| Select | Item | Cost ($) | Note |
|---|
Total Cost: $0