How Much Does an Architect-Designed Home Cost in Melbourne?

For the kinds of homes Borland Architecture designs, I would currently use a broad construction allowance of around $6,500 per square metre including GST for a relatively straightforward home, rising to around $10,000 to $12,000 per square metre including GST for a highly complex, highly specified home.

Those figures are useful for checking whether the ambition and budget are broadly aligned. They are a poor way to price an individual house.

We have a 392-square-metre home currently under construction in Mount Martha, known as Estuary House, with a construction contract of approximately $3 million. It was priced in 2025 and is currently within budget, which puts it at roughly $7,650 per square metre.

Another 392-square-metre home could cost considerably more.

The difference usually comes down to how much house you are building, how complicated it is to build, and what you put into it.

What does $5 million actually buy?

A $5 million construction budget makes the range easier to understand.

At around $6,500 per square metre, it could theoretically deliver about 770 square metres of building.

At $10,000 per square metre, the same budget is closer to 500 square metres.

At $12,000 per square metre, it falls to about 415 square metres.

I would not use those numbers as a pricing formula, but they show why two families with the same construction budget can end up with very different homes.

A relatively simple building can deliver far more floor area. Increase the complexity, glazing, specification, joinery, landscape and craftsmanship and the available floor area reduces quickly.

The important part is deciding which of those things actually matter to the family.

Floor area is only part of the cost

Imagine two 400-square-metre homes.

One is compact, relatively simple in form and perhaps arranged over two levels. The other stretches across the site around courtyards, has long roof edges, large openings, substantial glazing and several changes in geometry.

They have the same floor area, but very different quantities of wall, roof, glazing, structure, foundations and detailing.

Long single-storey homes can be particularly deceptive. They may look simpler because there is no upper floor, but spreading the same area across the ground can add a great deal of slab, roof and external wall.

Curves, large cantilevers, basements, difficult sites and very large areas of glazing can push the cost further.

None of these things are inherently poor decisions. We simply need to understand what they are contributing.

If a curved wall transforms an important room, it may justify the extra cost. If the complexity is doing very little for the people who will live there, I would question it.

Specification then moves the number again.

A kitchen can be beautifully designed and relatively restrained, or it can contain extensive custom joinery, complex stonework, specialist hardware and premium appliances. The same applies across bathrooms, flooring, lighting, windows, doors and the landscape.

On a substantial house, relatively small increases repeated hundreds of times add up quickly.

If the kitchen is genuinely the centre of family life, I am comfortable seeing more of the budget invested there. Another client may care far more about landscape, material quality or a particular level of craftsmanship.

A higher budget does not require every part of the house to become more expensive.

Comfort, health and building performance are already part of the baseline

For Borland Architecture, comfort, health and building performance are part of the basic design brief.

We want the house to remain comfortable through Melbourne's changing seasons, have good indoor air quality, maintain stable internal temperatures and avoid common problems such as overheating, cold internal surfaces, condensation and stale air.

That expectation should not be taken for granted.

These outcomes are not automatic in residential construction, and clients should satisfy themselves that whoever they appoint is designing and documenting the building to an appropriate standard. It is worth asking specifically about insulation, airtightness, thermal bridging, window performance, shading, ventilation and how those elements will be tested and verified once the house is built.

These decisions are difficult and expensive to correct later. If they are poorly resolved, the building will underperform regardless of how beautiful it looks. The occupants feel the consequences every day through uncomfortable temperatures, draughts, poor air quality, condensation or rooms that are difficult to use at certain times of year.

There is a cost to doing this properly, but I would be cautious about assuming building performance is the main reason an architect-designed home becomes expensive.

In our experience, floor area, architectural complexity and specification can move the budget much more dramatically. A complicated roof, excessive glazing or a large amount of bespoke joinery can absorb a significant amount of money without making the home healthier, more comfortable or better performing.

What is included in the construction cost?

This is where comparisons often become unreliable.

When I talk about a broad range of $6,500 to $12,000 per square metre, I am generally referring to the building itself and the components contained within it.

That would typically include the structure, building envelope, internal finishes, windows, doors, bathrooms, kitchens, built-in joinery, fixtures, fittings and the other elements required to complete the house itself.

It does not automatically include the wider project.

Depending on the site and brief, you may also need to allow separately for demolition, landscaping, pools, significant external works, professional fees, consultants, authority charges, finance, loose furniture and temporary accommodation.

Those additional costs can be substantial and vary considerably from one project to another.

So when someone tells me they have a $5 million budget, I want to understand whether they mean $5 million for the house itself or $5 million for the complete project.

That distinction can change the size, complexity and specification the budget can realistically support.

They are very different starting points.

Clients will sometimes also arrive saying something like:

“We have around $4 million and think we need 450 square metres.”

I would want to test both assumptions.

The family may genuinely need 450 square metres, in which case we need to understand what level of complexity and specification that budget can support.

We may also discover that 380 square metres gives them everything they need and leaves more of the budget available for the parts of the house they care about most.

If you are trying to establish a realistic budget for your own home, I would use the square-metre rate as an early sense check and then start looking closely at the complete project you actually want to build.

A compact 400-square-metre home and a highly complex 400-square-metre home may share a floor area and very little else financially.