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Think Outside the Square – Why sized-based quotes don’t work

Size doesn’t matter as much as you think it does. Whether you’re building a new house or extending an existing dwelling, the floor space involved is only one factor affecting the price. Other factors – like materials, site location and condition, design, and labour costs – have a huge impact as well.  That’s why you can’t trust a quote based on cost per square metre. These are likely to be very inaccurate and lacking in detail, which means you’re more likely to end up going over budget, or being unhappy with your results.

Here’s why square-metre quotes don’t work:


Renovation plansDifferent designs, different rates

When it comes to price, the details of the design are much more important than the overall size.

A relatively small 25sqm extension can vary wildly in price depending on design. You could require a simple box with one entryway and one window, or a long, narrow L shape that fits around the house. The design might include changes to the existing roofline or simply adding a lean-to. It could have a double-height ceiling or huge picture windows, multiple internal walls or none at all.

All these variations will obviously change the price. More internal walls mean more materials used. Changes to the roofline mean a longer build and higher labour costs. Large windows are more expensive, and trickier to install. Getting a professional builder involved at the design stage, or using a company that has one on board, can help you avoid spending thousands on a design that could end up being way out of your price range.

Renovation selectionsMaterials matter

Even if you choose a very simple design, costs can increase depending on your choice of materials. For example, 25sqm of wooden floorboards will be exponentially more expensive than 25sqm of linoleum or vinyl flooring. For bathrooms or kitchens, the quality and even size of floor tile can have a dramatic impact on your costs. Then there are endless choices of fittings: a single bathroom tap can cost anything from $60 – $1600.

Some material choices will be up to you, which means you can choose to keep the cost down if you need to – although choosing the cheapest possible option often ends up costing you more in the long run. Others will be non-negotiable – for example, you need to use the appropriate wall and flooring materials in a new bathroom to avoid water and/or steam damage.

MyHome BuilderCounting the cost of labour

Labour is one of the biggest costs in any build. The more complicated and detailed your design, the longer it’s likely to take – for example, changing the roofline or adding a new level to your house will both be complex and time consuming. That’s not just for the builders either, the more complex the project the more time involved for any other trades or specialist contractors.

Again, this is where working with builder or building company experienced in your specific type of building project comes in handy. Rather than giving you a simplistic quote based on square metreage, they will have the knowledge and experience to be able to consider things like labour and contractor costs, and factor those in from the beginning.

Feature tilesFancy features

When you’re building a new house, or adding an extension to your current home, it’s very easy to get carried away. You’re spending a lot of money, so you want to get the best possible result – your dream house.

But high-end features – like under floor heating, home automation, walk-in wardrobes, or even a spa bath – can add thousands to your overall cost. It’s important to think carefully about whether you really need them, or you just like the idea of having them. Under floor heating may not be necessary if you live in a warm climate, and a huge spa bath is only worth your while if you know you’ll use it frequently.


Whatever your building dreams, it’s important to have a realistic view of costs right from the start. You really don’t want to spend thousands on plans and then have to scrap or downgrade them later on. Avoid disappointment, and don’t trust simplistic, square-metre based building quotes – the truth is much more complicated.


MyHome Renovations has the experience and the tools to provide you with a fixed price quotation for your renovation project – get in touch today!

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