When building work goes wrong: six failure patterns and the control that stops each

Building failures are rarely mysterious. Looking at the defects and disputes that appear again and again in NSW, the same few patterns account for most of them. That is good news, because each pattern has a control that works.

This is a general list drawn from common industry experience and published guidance. It is not a collection of specific cases or a claim about any particular job.

1. The scope was never clear

What happens. The quote says "renovate bathroom" and nobody has written down what that means. The owner expects new waterproofing, the builder priced a re-tile. When the difference emerges, it is a dispute.

The control. A written scope, specific enough to check, with drawings and specifications attached, and an exclusions list. See reading a building quote and fixed-price vs cost-plus contracts.

2. Concealed work was covered before anyone checked it

What happens. Membranes, flashings, tie-downs and reinforcement are hidden within days. If one is wrong, the first sign is a leak or crack months or years later, and by then the cost of finding and fixing it is many times higher.

The control. Hold points: work stops, is inspected and recorded before it is covered. See hold points and the handover record and five envelope checks by stage. The certifier's critical stage inspections are a statutory minimum, not a substitute.

3. Materials or trades that do not work together

What happens. A sealant that does not bond to the substrate, a fixing that corrodes in contact with another metal, a membrane installed before the penetrations were set. Each trade did their own part correctly, and the junction failed.

The control. Specifying the system, not just the products, and sequencing trades so junctions are built in the right order. See material compatibility, order and junctions.

4. Surprises behind the wall

What happens. Renovating older buildings opens up conditions nobody could see: rot, termite damage, old services, non-compliant earlier work. If the contract has no way to deal with them, the first conversation about cost happens in the middle of the job.

The control. Investigation before pricing where possible, realistic provisional sums, and a clear variation process. See renovation hidden defects.

5. Changes made informally

What happens. "Can you just move that?" A change is agreed on site by conversation, nobody writes down the price or time effect, and the final account does not match anyone's memory.

The control. A rule that no variation is done without a written instruction and an agreed price. The record of variations then forms part of the handover.

6. Money ran ahead of the work

What happens. A large deposit, or payments that don't follow progress, leave the owner with little leverage if the quality or the programme slips, and little protection if the builder gets into financial trouble.

The control. For residential building work, NSW rules cap deposits at 10% and require progress payments to match the work done, according to the NSW Government. For jobs over $20,000, HBCF cover must be in place before the builder can take payment. Tie payments to inspected stages.

What to do if it does go wrong

1. Stop and document. Photograph the problem, date it and keep every message and invoice.
2. Check the contract and the record. What was agreed, what was approved, what was inspected.
3. Raise it in writing with the builder. Describe the problem and ask for a fix by a reasonable date.
4. Use the formal path if needed. According to NSW Government guidance, either party can ask Building Commission NSW to help resolve a dispute. An inspector may inspect and, if they find the trader responsible for defective or incomplete work, can issue a rectification order. If the matter is not resolved, the next step is the NSW Civil and Administrative Tribunal (NCAT).
5. Watch the time limits. Statutory warranties run for six years for major defects and two years for other defects, from completion, and a claim must be made within those periods. Our article on statutory warranties explains how.
6. Get independent advice for anything significant: a building consultant or engineer for the technical question, a lawyer for the legal one.

For strata schemes, the owners corporation is the party that deals with common property defects, and strata defects reports have their own timing rules.

What this means when choosing a builder

Ask each builder how they deal with the six patterns above. Specific answers about scope documents, hold points, trade sequencing, variations and payments tell you more than any slogan. The twelve questions to ask a builder turn this into a checklist.

Working with us

These patterns are the reason we work the way we do. See How We Build, or get in touch to discuss your project.

Sources

• Resolving disputes, NSW Government
• Contracts for residential building work, NSW Government
• Home Building Act 1989 (NSW), NSW Legislation

This article is general information, not legal or technical advice. If you have a dispute, get advice on your specific facts and act within the time limits. Full website disclaimer