1. Initial complaint: The homeowner will need to contact the builder and raise the issue, in an effort to resolve the dispute informally.
2. Mediation: If the dispute cannot be resolved informally, the Building Commission will provide mediation services to try to bring the parties to a resolution. The mediation will be conducted by a neutral third-party mediator who will help the parties communicate and find a mutually acceptable solution.
3. Adjudication: If the dispute cannot be resolved through mediation, the homeowner can apply to the Building Commissioner for Adjudication. This is a fast-track and cost-effective process where an independent Adjudicator will make a decision on the dispute.
4. Legal action: If the dispute is not resolved through the above steps, the homeowner may consider taking legal action against the builder. This can include filing a lawsuit in court or taking the matter to the State Administrative Tribunal.

It’s worth noting that the Building Commission in Western Australia provides a free service for resolving disputes between homeowners and builders and it’s highly recommended to take advantage of it before pursuing legal action.