Mcmullen builders

Extensions from $10K and up!


✓ Conventional Construction
✓ Energy Proud designs
✓ Council Approval Support
✓ And much more!

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trusted supplier
Quality #1

House Extensions in Whyalla

Extending Your Home in Whyalla

The ability to extend and add on to your home is closer than you think. McMullen Builders will help you design and build the answer to your needs. Work with a team who has decades of experience building a long list of various custom designed extensions in Whyalla.

Let us help you through this journey for any extension in Whyalla with:

Project Management
Council Approval Support

Whyalla Home Extensions

Quality Assured from the beginning to the end

Using McMullen Builders to take care of the ordering, storage of materials off site, tracking the build and giving you constant build up-dates; allows you to stay constantly informed, while helping you to remove unnecessary steps in the building process. McMullen Builders are a 3rd Party Quality Assured Company to ISO 9001:2015

Old & New Houses
All Extensions
Council Approvals Support
All Building Work
ISO 45001 Certified
Creating a bridge from problem to solution for:

Council Approval Support
No Idea of Costs? - Ask us for help

Why our customers choose us

The quote is the price

We invest the time when quoting and in the follow-up communication to ensure that the quote you receive is the price you pay.

Making your space, yours, sooner

As the technology used in building continues to evolve and improve, by embracing these new advancements, we’re able to complete most projects in half the time frame compared to others in the industry.

The small touches

Making your house still feel like your home during the project is paramount to us. Taking that extra time at the end of the day to tidy and minimise our space in your home, is time well spent.

In-house expertise

Extensions can come in all shapes and sizes, by having a large team of fully qualified trades-people and engineers, it means we can quote and build to perfectly match what you have in mind.

Post-build care

At McMullen Builders, we believe that although you can’t predict an emergency issue, you can be prepared for it. We offer a 24 hour on-call service to provide fully qualified experts when you need them most.


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Our Customers

“Everything went smoothly through the entire process. Well done team.”

John Starsy

“Everything went smoothly through the entire process. Well done team.”

John Starsy

“Everything went smoothly through the entire process. Well done team.”

John Starsy

We can add that much needed extension to give you the space you need.

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Why McMullen Builders?

Everything in one place

McMullen Builders pride themselves on having the ability to source a large majority of the necessary supplies from our own in-house facilities and local suppliers. Locally made quality Assured to ISO 9001:2015

A solid foundation to grow on

With over 30 years of experience and a respected member of the Housing Industry Association, that solid foundation allows us to continue to embrace new technology and systems. We strive to find new ways to help us achieve your goals, while maintaining the quality, speed and accuracy that we are synonymous with.

A team you can rely on

The combined selection of business that we have under one roof means that we have teams of experts working on jobs together, over seen by the same business. By stream lining the process it allows us to maintain fast builds for you, by being accountable and contactable during the whole process.

ISO 9001:2015
AS/NZS 4801:2001
ISO 45001:2018
ISO 14001:2015.

Get in touch today

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Browse below with some of our answers to the Frequently asked Questions. or give us a call anytime.

Can’t find what you’re looking for?

If you can’t find the answer to your question below, please let us know.

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Which Design is right for me?
How do I choose the right builder for me?
What’s the difference between extensions and renovations?
What Guarantees do we get?
How long will the work take to complete?
What is a Building Contract and a progress claim?