Not sure whether that crack in the stucco, that uneven patch in the floor, or the wall with a bow in it are defects in your new home that you can insist get fixed? There's a new guide to help with that.

The Ministry of Business, Innovation and Employment (MBIE) has published a Guide to tolerances, materials and workmanship in new residential construction 2015 to help homeowners decide if there is a problem that should be fixed under the 12-month defect repair period.

Everything from roof to sub-floor is covered. That rusty nail in the guttering that’s left a stain? Yes, it’s a defect. So is the rubbish blocking a sub-floor vent. The guide tells you how much “bend” is allowed in a wall, how wide a crack can be before it’s a defect and much more.

The guide covers aesthetic issues (e.g. what is considered a reasonable slope in a floor, or what is an acceptable appearance for a newly painted wall) in new builds and additions. It does not cover tolerances for repairs, renovations, or alterations within existing buildings, though in some circumstances it could be used for guidance.

It applies at any price, whether or not other consumer protection measures and the $30,000 threshold apply.

The guide was written with advice from industry to support the implied warranties in the new consumer protection measures, which came into law on 1 January 2015.

Builders can use the guide to ensure their clients understand and agree on acceptable levels of tolerances, materials and workmanship for new residential building work. Contractors and clients also have the option of mutually agreeing to their own expectations, preferably within their written contract.