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House Extension Guide

So you are thinking about creating a house extension and wondering where to start?

Adding more living space is more popular than ever in the kiwi housing market, but many people start their extension project without knowing enough about design, the council consents & the building or construction process.

We help guide you through the process below.


What do you need to consider before building house extensions in Auckland. How does a house extension cost? Here is a House extension guide for getting started.

Whilst it can be a little overwhelming with all the information required in order to get that extension out of the ground, the very first step would be to go through the basics.

Ask yourself
1) Why do you want to extend your home?
2) How will it affect the flow of the original home?
3) Do you have room to extend outwards or is building upwards the only way?
4) Do you think it will add value to your home?
5) What is access like? How will you get heavy equipment/ rubbish etc in and out of the area being extended?
6) What do you want to invest in the project? Note- The most simple straight forward small outwards house extension starts at $65,000
7) Will you be going to the bank for finance?


Costs for house extensions in Auckland vary widely depending on their size, style, location and specifications. You will really want builders advice to tell you specifically what you can get for your maximum budget, however this is very hard to do as you have no plans or specifications. So at this stage the best guide would be a square meter average (Remember that the standard of specification you choose will have an enormous influence on the build cost)

Single storey house extension price guide (Minimums)
Basic Quality House Extension – $2200 – $3300 per square meter
Good Quality House Extension $3300 – $4500 per square meter
Excellent Quality House Extension $4500 upwards.

Once you have a good idea of why you want to extend and what you want to invest, you can dive into the details a little more. Obtain your property file from Council. More information can be found here- https://www.aucklandcouncil.govt.nz/buying-property/order-property-report/Pages/order-property-file.aspx . The property file will show all the existing information about your property including the original construction drawings, boundaries and services. Its the document that is crucial to getting your project started as it’s the baseline of what we will need to draw and plan your project. The things we need to consider from the property file are things like:

• conditions on the existing site;
• services;
• boundary lines;
• height to boundary issues;
• flooding;
• surface coverage;
• rights of way;
• engineering or geotech requirements


Now you have everything in place, its time to get the ball rolling and get in contact with us to have a chat. Free phone us on 0800 33 66 77

Remember, house extensions are planned and built to budget, so be specific of what you want and what you wish to spend. We will organise to come out to look at the current home and discuss your ideas. Keep in mind, the design of any extension is an integral part of your existing home’s structure. This means it should blend in, making use of the same materials to maintain the same look or flow as the existing dwelling. If you are considering a second storey addition be aware that this is significantly more expensive and complicated from a construction point of view.

You’ll need to  give us an idea of your budget (Include a 10% buffer for any additional ‘surprises’ may be unforeseen) ; we can assess what is possible and discuss it as a team – we may even be able to do a job for less, in which case you could have more to spend on other things.

If you are happy with us and want to move forward after meeting, we will organise drawings to be done.


Drawings are required for all house extensions. They are the working drawings that are used by the builders and need to be approved by Auckland City Council before we can lift a hammer. In many extensions, there are requirements for engineering and other planning/resource consents – We’ll draw up all the paperwork for you. We have an intimate knowledge of the design & structural issues involved as well as the council requirements. Our task is to make your home extension process as straightforward as possible.

Once you approve the design, we can provide some ideas of provisional pricing and send it to council for your house extension Consent.

When the Council has approved the plans, we provide firm pricing & contract, then we start building!