A warning changes to insulation codes could result in low confidence from the business sector

Building and Construction Minister Chris Penk is looking at changing the H1 Energy Efficiency Building Code introduced last year, which aims to reduce energy for heating homes by 40 percent.

Certified Builders Chief Executive Malcolm Fleming says the industry has adapted the code.

He says manufacturers have also invested heavily in new plants and machinery, and so removing H1 undoes much of that business investment.

Fleming adds the requirements costs are small for significant long term gain.