Ask five builders the cost to build a house in Sydney and you’ll get five different answers. That’s because the real number depends on your block, your design and the inclusions you choose, not a single figure that applies to every home. This guide walks through the parts of your build that actually move the price, so you can budget properly before you request a quote.
What Actually Drives the Cost of a Custom Build
Site costs come first. Your block’s slope, soil and access all affect what is needed before a single wall goes up. From there, your floorplan, storey count and chosen inclusions shape the rest of the price. A simple rectangular layout with a straightforward roofline generally costs less to build than one with multiple wings, changes in roof height or a long run of glazing, even at the same floor area. It’s why the costs of building a custom home can vary so much between two homes of a similar size.
Build costs are also shaped by things outside your control. Material and labour prices move with the broader construction market, and council contributions differ from one local government area to the next. A quote is only accurate for the block and design it was written against.
Site Costs: The Variable Most Buyers Underestimate
Before your build cost even starts, your site needs preparing. Depending on your block, this can include:
- A site survey and soil test, to confirm what footings and slab your home needs
- Demolition, if you are on a knockdown rebuild
- Earthworks, if your block slopes or needs levelling
- Connecting power, water and sewer to the new home
- Council contributions, which vary by local government area
None of this is optional, and it rarely shows up in a per-square-metre figure quoted online. Two blocks in the same suburb can carry very different site costs, depending on soil type and slope alone. This is one reason we walk your specific block before we put a number in front of you.
Where Our Inclusion Tiers Fit In
Every BuildTec home starts with our Classic Collection as standard. From there, moving to Prestige adds $12,000 for a single storey home or $15,000 for a double storey or acreage home, and moving to Platinum adds $35,000 or $45,000 respectively.
Knowing these figures upfront means you can budget properly before you fall in love with a finish you haven’t priced in. Each tier lifts the standard of finish across the whole home, not just one room, so the jump in price reflects a jump across your kitchen, bathrooms and fixtures together. Upgrades across the tiers can include things like ducted air conditioning, stone benchtops or a wider front entry, on top of what is already included as standard.
Single Storey, Double Storey and Acreage: Why Build Type Changes the Number
A double storey or acreage home costs more to build than a single storey home of the same floor area. Extra levels need stronger footings and staircases, along with more complex site access during construction. Acreage builds often carry their own site costs too, from longer driveways to on-site wastewater systems where town sewer is not available. Our guide to designing a home for acreage living covers these in more depth.
This is why the same floorplan can carry two different price tags depending on the block it sits on and the storey count you choose.
The Paperwork That Locks In Your Price
Two documents do the real work of confirming your final figure. The HIA Preliminary Agreement sets out the scope and price before you commit to a full contract, and the HIA Contract that follows sets out your inclusions, your price and your estimated timeline in writing. A BASIX certificate is also required for NSW builds, confirming your home meets energy and water efficiency requirements before construction can proceed.
Getting these steps right upfront is what stops a quote turning into a moving target once construction starts.
Comparing Builder Quotes Properly
Two quotes for a similar looking home can differ by tens of thousands of dollars, and the gap is usually in what is included, not in the builder’s margin. When you compare quotes, look past the headline number and check:
- The level of finishes included as standard
- What site costs are allowed for, and whether they are capped
- Which appliances and electrical inclusions are included
- Whether any items are listed as a provisional sum, and what that sum actually covers
- Whether the figure is a confirmed price or an early estimate
A lower number on paper does not always mean a lower final cost once these are accounted for.
Budgeting for the Unexpected
Even with a confirmed price, most builds carry some allowance for the unexpected. Weather delays, longer lead times on certain materials, or a site condition that only shows up once earthworks begin can all affect a build. Before you sign, ask your builder what happens if one of these comes up, and whether it is already covered in your contract or treated as a separate variation. A clear answer here tells you a lot about how a builder actually prices their homes.
Why We Price the Way We Do
We agree your price, your inclusions and your timeline before you sign anything, so the figure in your contract is the figure you pay. There’s no estimate designed to win the job and increase later.
FAQs
Frequently Asked Questions
Straight answers to the questions we hear most before a build begins.
What is included in the price BuildTec quotes?
Every BuildTec home starts with our Classic Collection as standard, covering the base inclusions across the home. Site costs, council contributions and your chosen finish level are confirmed before you sign, so the figure in your contract reflects what you will actually pay.
How much more do Prestige or Platinum inclusions cost?
Moving from Classic to Prestige adds $12,000 on a single storey home or $15,000 on a double storey or acreage home. Moving to Platinum adds $35,000 or $45,000 respectively. These figures are confirmed upfront, before you commit to a design.
Can I compare quotes from different Sydney builders fairly?
Only if you compare the same things. Check the level of finishes, what site costs are allowed for, which appliances and electrical inclusions are included, and whether any items sit outside the quoted figure as a provisional sum. Two quotes with the same total can still leave you with very different homes.
