A review is being launched into the rules around shoddy building products in New Zealand.

The Ministry of Business, Innovation and Employment is due to look over its building product assurance rules after turning up a wave of dodgy materials over the past few years.

Building Industry Federation CEO Bruce Kohn says they have been pushing for the review for years now.

"When you have the plumbers, the electricians, gasfitters as well as the glass people, importers and local producers all saying there are problems we know enough to be able to get on with it."

Kohn says the sketchy parts are mainly coming into the country through cowboys.

"They see that they can make a buck then there's the odd builder who says 'well if I take this cheaper stuff then I can cut some pricing off my bill' then they go for it."