"It's Within Tolerance": What That Actually Means When Your Builder Says It

Somewhere on the Central Coast right now, a homeowner is standing in a half finished hallway looking at a doorway that is visibly out of square, and a builder is telling them not to worry because "it's within tolerance". Maybe the builder is right. Maybe he is not. The problem is that the homeowner usually has no way of knowing, because "within tolerance" gets said as though it were a legal ruling, when most of the time nobody on site could tell you where the tolerance is written down or what the number actually is.

I am an architect, and I have sat on both sides of this conversation. So here is the honest version: what the phrase really refers to in NSW, the actual numbers, the situations where the builder has a point, and the situations where the phrase is doing the work of a shrug.

There is no law called "tolerance"

Start with the thing that surprises people. "Within tolerance" has no statutory definition in NSW. No act of parliament defines it. It is not a magic phrase that ends an argument, and a builder saying it does not shift any legal ground at all. What the phrase gestures at is a real and reasonable idea, which is that buildings are made by hand, from natural materials, on real sites, and perfect is not the standard. The standard is acceptable, and somebody has to say what acceptable means in millimetres.

In NSW, the document that does that job is the Guide to Standards and Tolerances 2017, published by NSW Fair Trading. It is a guide, not legislation. It does not override the National Construction Code or the Australian Standards, and it says so itself. But it is the reference that Building Commission NSW inspectors, private building inspectors and the experts who appear at NCAT all reach for when someone asks whether a piece of work is defective. When your builder says "within tolerance", this is the book they are implicitly citing, whether they have read it or not.

And that is the part worth knowing, because the guide cuts both ways. Builders quote it as a shield. It is also full of hard numbers that classify plenty of "she'll be right" workmanship as defective. Most owners have never opened it. More than a few builders are counting on that.

The numbers that actually matter

The guide runs to well over a hundred items. These are the ones that come up in almost every dispute I see, with the figures as the guide states them.

Walls and frames out of plumb. Frames are defective if they deviate from plane, meaning horizontal or vertical bow, by more than 4 mm in any 2 m length of wall. The same 4 mm in 2 m test applies to deviations across finished wall surfaces. A spirit level and a straight edge from any hardware store will tell you in five minutes whether a wall passes.

Floors that are not level. New floors are defective if, within the first 24 months of handover, they differ in level by more than 10 mm in any room, or by more than 4 mm in any 2 m length. Note both halves of that sentence. There is a number, and there is a clock.

Doors and windows. Doors and windows are defective if they bind or jam as a result of the builder's work, and defective if they let water in when closed. There is no tolerance for a door that will not operate properly. A doorway that is visibly out of square is measurable against the framing and lining tolerances above, and "you'll never notice it once the furniture is in" is not one of the published tests.

Plasterboard. Nail popping in plasterboard is a defect if it appears within the first 24 months. Joints, trowel marks and other finish blemishes are assessed from what the guide calls a normal viewing position, which I will come back to, because it is the strongest genuine card the builder holds.

Architraves and trim. The faces of architraves and skirtings are defective if they are not aligned and flush at mitres and butt joints and the misalignment can be seen from a normal viewing position.

Cracking. Some hairline cracking as a new building dries out and settles is normal and expected, and the guide says so. But it is not open ended: cracking is assessed against width limits, and as a working rule cracks wider than about 2 mm after the first 12 months are beyond what the guide treats as acceptable shrinkage. Anything that wide, or any crack that keeps growing, deserves a proper look rather than a paint over.

Notice the pattern in the time limits. Many items are only classed as defects if they appear within 12 or 24 months of handover. That is fair to builders, because buildings move most in their first two years. It is brutal to owners who wait politely. If something looks wrong, measure it, photograph it with a date, and put it in writing now. The clock is part of the test.

When the builder is actually right

Credit where it is due, because this phrase is not always a dodge.

The guide assesses surface and finish complaints from a defined normal viewing position: standing 1.5 m away or more, or 600 mm for appliances and fixtures, in ordinary diffused light rather than harsh glancing light. A plasterboard joint you can only find with your cheek against the wall and a torch held flat against it is, genuinely, not a defect. Late afternoon sun raking down a hallway wall will expose shadowing in even excellent stopping work, and standard plasterboard finishes are not required to survive that test. If a dead flat wall under critical light matters to you, that is a level 5 finish, and it has to be written into your contract, because it will not be implied.

Timber moves, concrete shrinks, brickwork grows, and the guide's allowances exist because a handmade object on a reactive clay site cannot be machined to furniture tolerances. An owner with a laser level hunting millimetres that sit comfortably inside the published figures is not building a case, they are burning goodwill they may need for the defects that matter.

What "within tolerance" can never excuse

Here is the boundary that matters most, and the one the phrase is most often used to blur.

Tolerances describe acceptable variation in work that was otherwise done properly. They do not excuse the wrong work. The guide's own introduction makes the point with an example: a builder who installs untreated pine in an external deck, where a durable timber was required, is likely to have to replace it. No viewing distance, no millimetre allowance and no amount of confident delivery makes non compliant work acceptable.

Above the guide sits the Home Building Act. Every residential building contract in NSW automatically includes the statutory warranties in section 18B: work done with due care and skill, in accordance with the plans and specifications, with suitable materials, compliant with the law, and resulting in a dwelling reasonably fit to live in. These cannot be signed away, and no contract clause or tolerance argument sits above them. They run for 6 years from completion for a major defect and 2 years for everything else, and you must give the builder written notice within 6 months of a defect becoming apparent. I have covered the warranties in detail in my guide to the questions to ask before signing a building contract in NSW.

So when you hear "within tolerance", the real question is simply: which published figure, in which document, and does the work actually sit inside it? A builder who is right will happily answer. Evasion on that question tells you a lot, and I have written about the other warning signs worth taking seriously.

The gyprock or the frame

A version of this argument I hear constantly, and the one that prompted this article: doorways out of alignment, and a builder insisting the problem is "just the gyprock, not the frame". Sometimes true. Also, mostly beside the point. You did not contract the frame carpenter and the plasterer separately. You contracted a builder to deliver a finished, compliant house, and the statutory warranties attach to the whole of the work. Whether the wonky opening lives in the lining or the studs is the builder's problem to diagnose, not yours. Your job is only to establish that the finished surface is outside the published figures, and a straight edge across the opening will settle that without anyone's opinion.

What to do when you disagree, in order

Measure and document first. Straight edge, level, tape, camera, dates. Tie each item to a number in the guide where you can. A defect list with millimetres in it reads completely differently from a list of feelings.

Put it in writing to the builder. Calm, specific, itemised, and keep a copy. This starts the statutory notice clock properly and gives a good builder the chance most of them will take, which is to fix it.

Get an independent inspection if it stalls. A private building inspector's report, written against the guide, the NCC and the standards, converts the argument from your word against theirs into evidence. On anything structural, an engineer's opinion is worth every dollar.

Lodge a complaint with Building Commission NSW. It is free. An inspector attends, typically within about 22 working days, and can issue a rectification order that is a breach of the Home Building Act to ignore. Roughly seven disputes in ten resolve at this stage without going further.

NCAT is the backstop. The tribunal hears home building claims up to $500,000 and can order rectification or payment. By the time you are there, the case usually turns on competing expert reports, which is exactly why the measuring and documenting at step one matters so much.

Where I fit

The cheapest version of this whole argument is the one that never happens. Tolerance disputes thrive on vague documentation, because when the drawings do not say what standard was required, "within tolerance" fills the silence. A properly detailed set of drawings and specifications, and independent eyes on the build at key stages, is how you close that gap before it opens. That is a large part of what I do for clients on the Central Coast, and it starts with a free site assessment. If you are earlier in the journey, start with before you build on the Central Coast.