With the move towards trade self certification, the onus for cerficates of compliance is on tradespeople themselves and there is reduced scrutiny by authorities.
This means that you should:
• Choose professionals to do any electrical wiring. Any work suspected to have been carried out by amateurs should be checked by a licensed contractor.
• Ensure that electrical and plumbing work is only undertaken by contractors registered with the relevant authority (usually indicated by a registration number)
• Request a compliance certificate when work is completed.
• Select contractors who are insured against accident and negligence.
Builders - guarantees
In many states, builders need to provide "guarantees" on their work. This broadly means the builder takes out insurance, on behalf of their client so that if any defects are discovered several years after completion, they can be fixed at no extra cost to the homeowner.
The work must be of significant value to invoke this guarantee (eg, a minimum of $12,000 in Victoria), and in some states, work like plumbing is excluded. When you engage a builder, check that he is registered with the appropriate authorities and the work is insured.
Each state’s requirements for building guarantees are different so it’s best to check with your building surveyor, your Building Services Authority or similar authority. Generally, owner-builders don't need to guarantee themselves that their building work is up to standard (although in Queensland, for example, they need a Building Services Authority owner-builder permit).
In some states, owner-builders need to provide insurance if selling within seven years of the building permit or similar regulation, to protect subsequent owners. In such states, it is necessary for the vendor to firstly arrange an inspection and report on the building work, by a building professional such as Archicentre, after which the relevant insurance may be obtained.
Protect yourself against illegal constructions
By law, illegal existing extensions, renovations, home improvements and repairs become the responsibility of the home buyer. They may be dangerous, and if substandard, they may have to be demolished prior to further building work.
Check with the vendor or your solicitor that all works have been done with local council building approval or make an enquiry at your local council's building department.