Construction companies will face additional liability for completed residential buildings that do not comply with building code requirements around cladding or other items under consumer protection reforms proposed by state and territory building minsters on Friday.

COAG building ministers meeting in the week that combustible cladding spread fire up the face of Melbourne's Neo200 residential tower said in a communique that they would legislate, if necessary, to ensure builders owed an ongoing duty of care to apartment owners to supply a building that met required standards.