Your home. Your rights. Know the standards.
Defend My Build equips Australian homeowners and independent building inspectors to understand technical building standards, document defects, and take decisive action against substandard building work.
Defend My Build is strictly reserved for consumers and independent inspectors. Building companies, volume builder representatives, and industry lobby associations (HIA/MBA) are strictly prohibited.
Tools
Everything you need to defend your build
From first defects notice to final resolution — free and open to all Australians.
Diagnostic Tools
Interactive cutaway house navigator, slab deviation calculator, crack classifier, and EOT delay auditor.
OpenStandards Library
61 standards (21 free to read) — NCC chapters, WA legislation, AS references. Know what your builder had to deliver.
OpenYour Rights
What builders must do, cannot do, and the timeframes they must meet. WA & national legislation explained.
OpenLegal Templates
33 ready-to-use templates — defect notices, final demands, DEMIRS complaints, EOT disputes, and more.
OpenCommunity
Real accounts from Australian homeowners. Search by builder, state, or defect type.
OpenThe Rules That Bind Them
Key standards that protect you
These are the government and industry standards that define what a builder must deliver. Not opinions — binding obligations.
WA Guide to Standards & Tolerances 2019
DEMIRS — WA Government
- →Clause 2.11: Slab finish is defective if not suitable for documented applied finishes (inc. decorative/polished concrete)
- →Clause 2.08: Floor defective if >4mm in any 2m length within 24 months
- →Clause 2.12: Repairs must match existing work — if not possible, entire surface replaced
PCCA Position Statements
Polished Concrete Council of Australia
- →Slab protection is the builder's responsibility — not the polisher's
- →Polishing contractor cannot fix concretor defects without grinding deeper (changes the finish)
- →Boothole marks, screed marks, rough edges at internal corners cannot be rectified by polishing
Diagrind DPC2021 Specification
Industry specification — ACI 300-R, AS 3610.1
- →Minimum S32 (32 MPa) to AS1379 — mandatory
- →Max 3mm deviation under 3m straight edge
- →Max 1mm undulation over 300mm
- →Hydrocarbon resin curing agent not permitted
AS 2870-2011
Australian Standard — Referenced in NCC 2022
- →Residential slabs and footings
- →Defines crack damage categories 0–4
- →Category 3 & 4 cracks are defective and require rectification
- →Deviation >1:150 overall is undesirable
AS 3600-2018
Australian Standard — Referenced in NCC 2022
- →Concrete structures
- →Floor tolerance requirements
- →32 MPa minimum for pneumatic-tyred traffic / polished floor surfaces
- →Abrasion resistance requirements by use
CCAA — Finishing Concrete Flatwork
Cement Concrete & Aggregates Australia
- →Smooth surface finish is NOT evidence of good compaction underneath
- →Dry-shake toppings must not be used to mask defective concrete
- →Incorrect finishing causes crazing and delamination
How It Works
From defect to resolution
From identifying your defect to submitting evidence to DEMIRS or the Building Commission.
Identify your defect
Use our standards library to understand what the builder was required to deliver — and what they failed to do.
Build your evidence
Templates for evidence submissions to DEMIRS, the Building Commission, and your legal representative. Based on real standards.
Take action
Know which authority to contact, what to say, and what supporting documents to attach. We map the complaint pathway for WA residential builds.
Why This Exists
Built by someone who lived it
Defend My Build was created by a Perth homeowner who spent four years fighting a national building company over defective work — including a polished concrete slab poured with the wrong product, inadequate reinforcement cover, and backdated engineering documents.
The process is designed to exhaust you financially and emotionally. Builders have institutional legal resources. Homeowners have a contract they can barely read. This platform exists to level that playing field — with the actual standards, the actual tolerances, and the actual complaint pathways that apply.
This is not legal advice. It is industry knowledge — the same references that expert witnesses, building consultants, and quantity surveyors use — made accessible to the people who need it most.
Industry bodies & standards referenced
Get In Touch
Ready to defend your build?
Have a building dispute question, or want to contribute a case study or industry document to the standards library? Reach out — or jump straight in.