An owner-builder is someone who is the owner of the land and chooses to undertake the building project as the “builder”. Building Services Board (BSB)
Under the Building Services (Regulations) Act 2011, any person undertaking building work where the value exceeds $20,000 is required to be registered with the Building Services Board (BSB). As the landowner you may apply to the BSB to be approved as an owner-builder. The application for this is in the form of a statutory declaration. Conditions apply when approval is granted. See the Building Commission's website for application forms and information relating to owner-builders: http://www.buildingcommission.wa.gov.au/
You may be an owner-builder for any project without approval if the value of works is less than $20,000.
Value of works includes all materials and labour. The cost of labour must be calculated even if you are providing the labour component yourself. To assist in estimating the value of work, the approximate cost of construction as of June 2010 is $1000 per square metre of building. Up-to-date costs can be obtained from the Housing Industry Association or the Master Builders Association.