The supplier, Symonite, said it has "simply lost faith in [the] ability and decision making" of Codemark, which the Ministry of Business, Innovation and Employment markets as the gold-standard of building product assurance schemes.

"In recent months, we have had cause to question the veracity of this scheme," Symonite director John Cobb said in an email to customers.

Last week MBIE suspended six certificates covering 13 types of panel, saying they lacked evidence of compliance with the Building Code. . . . . . .