Why “Per m² Rates” Don’t Apply to Custom Builds & Renovations. (and why they can be misleading)

 When you start looking for a builder, one of the first questions that comes up is:
“So, what’s your price per square metre?” 

It’s a fair question — you want to know roughly what things cost and where a builder sits in the market. But when it comes to architecturally designed, high-performance homes or major renovations, a single number like $X per m² can be more confusing than helpful.

At Two Hammers Construction, every home we build is one-of-a-kind. We collaborate with architects and clients from the start, focusing on buildability, budget clarity and performance — not cookie-cutter formulas.

Where the “Per m² Rate” Came From

The idea of a per square metre rate started in the world of volume building — production builders repeating the same home design hundreds of times on identical, flat suburban blocks. In that space, costs can be averaged out and neatly packaged into marketing slogans.

But in custom design and renovation, no two homes are the same. Every block, every brief, every material selection brings its own variables. Trying to compare these with a single figure per m² is like trying to value a painting by its size — it tells you nothing about what’s inside the frame.

Why “Per m²” Rates Don’t Stack Up for Custom or High-Performance Homes

There are hundreds (if not thousands) of factors that influence the true cost of a bespoke home. Here are a few of the biggest:

1. Every site tells a different story

Soil, slope, services, access, and bushfire zoning (BAL) all shape the build. A sloping bush block in Yallingup or Margaret River might require retaining walls, deep footings, or special access equipment. A flat suburban block in Busselton? Totally different scenario.

2. Design and detailing drive the build

A raked ceiling, polished concrete floor or large custom window doesn’t add much floor area — but it adds engineering, structure and time. High ceilings, multiple wet areas, outdoor living spaces and passivhaus design elements all influence cost far more than raw size.

3. Performance has its own price — and payoff

High-performance homes are built differently. Continuous insulation, airtight wraps, quality glazing, HRV systems and precision carpentry take extra skill and time — but they deliver a home that’s comfortable, healthy and energy-efficient for life.

4. Renovations are their own beast

Working with existing structures means demolition, tie-ins, re-levelling and problem-solving on the fly. Things like asbestos removal, re-plumbing or upgrading old wiring can quickly shift costs and no “per m²” rate can predict that.

5. Not all square metres are created equal

A square metre of bathroom costs far more than a square metre of hallway. Wet areas demand multiple trades — waterproofing, tiling, plumbing, electrical, painting etc— while a living room might only need a plasterer and painter.

6. Craftsmanship, supervision and labour

Who’s actually building your home? Is your builder on-site, or have they handed it off to juniors? At Two Hammers, Stefan leads every project personally, working alongside skilled local trades. That hands-on approach makes a big difference in quality and accountability.

What We Focus On Instead

We don’t deal in square-metre guesses — we deal in facts, scope and collaboration.

Here’s how we approach costing:

• We start with your goals. We talk about what you want to achieve, your level of finish and what performance or sustainability goals matter to you.

• We build from real data. We show examples of completed projects with detailed breakdowns — site conditions, inclusions and timelines — so you can see exactly what influenced cost.

• We collaborate through design. Our partnership process means we collaborate with our partnered architects early to discuss costs and constructability from concept to contract. This means that we aren’t making decisions about design or construction during the build and we are finding the best solutions to meet your brief and budget before we are onsite. No decision fatigue, budget blow outs or hidden unknowns.

• We focus on long-term value. Our clients build homes they plan to live in for decades — so we prioritise durability, performance and craftsmanship over short-term savings.

• We’re transparent about cost control. We clarify how cost is controlled during your build, the quality of workmanship, the level of supervision and how long it will take 

Why This Matters

Building or renovating isn’t just a transaction — it’s a long-term relationship and an investment in comfort, quality and lifestyle. When you chase the lowest per m² figure, you risk ending up with a build that compromises performance, detailing or longevity.

Our approach keeps you informed from day one. By grounding every decision in real data and open communication, we ensure your home isn’t just built — it’s built right.

Takeaway

If you’re planning an architectural renovation or a high-performance home, a “per m² rate” won’t tell you what you need to know.

Instead, have a real conversation about your design, your site and your expectations. That’s how you get a build that truly reflects your vision — and stands the test of time.

At Two Hammers Construction, we don’t build average homes — we build the best they can be built.