Buying guide
House extensions: Everything you need to know
Read this before you break ground
AI summary
Considering a house extension? Costs can range from $50,000 for a basic room to over $400,000, depending on size, materials, and site conditions.
The process involves hiring an architect, securing finance, and obtaining council consents before construction. A detailed, lawyer-reviewed contract is essential to define scope and timelines. Always plan for a 15% budget contingency for unexpected costs.
The project is officially finished once the council issues a Code Compliance Certificate (CCC).
How much does a house extension cost?
Rough guide to NZ house extension costs
What affects the cost of house extensions?
Extent of extensions
Materials used
Your site’s conditions
Council consents
In most cases you'll need to get consent before extending your property.
The NZ house extension process
It's a good idea to get a clear idea of costs before you start a project
If you can do some work yourself you could save thousands of daollrs.
Hot tips for building an extension
The contract is key
Think about your neighbours
Prioritise consents
Demand cost and timeline certainty but plan for blow outs
Build for the future
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