Less money is being spent on residential building alteration work, non-residential work more resilient

The value of building alteration work has fallen for two years in a row and may be in a long term decline.

According to Statistics NZ, the total value of building consents issued for structural alteration work for all types of buildings was $4.842 billion in the 12 months to April this year.

That's down $75 million (-1.5%) compared to the 12 months to April 2025, and down $212m (-4.2%) compared to the April year peak of $5.054 billion in 2024.

The biggest decline is for residential alteration work.

Building consents are only required for structural alterations to a building, such as adding extra rooms, but are not required for mere redecorating or refurbishment that doesn't involve altering the structure of a building.

In the April year $2.243 billion of residential alteration work was consented, up by $56m from the April 2025 year, but down $258m (-10.3%) from the April 2024 year.

The decline in residential alteration work also shows up in Statistics NZ's Value of Building Work survey, which charts the value of project commencements in the building industry.

This shows residential alteration work commencements have declined for two years in a row, down from $3.309 billion in the 12 months to March 2024, to $2.931b in the 12 months to March 2025, to $2.637b in the 12 months to March 2026.

That's a fall of $672 million (-20.3%) over the last two years.

That drop in alteration work may be part of a longer term decline.

The total value of consents issued for residential alteration work amounted just 11.3% by value for all residential building consents issued in the 12 months to April.

That percentage has more than halved from what may be described as the glory days of alteration work from 2009 to 2012, when alteration consents accounted for between 21.6% and 24.1% of the total value of all residential consents.

However, alteration work remains more buoyant for non-residential buildings, which includes commercial buildings such as shops, offices and industrial buildings and other types of buildings such as hospitals and schools.

Consents were issued for $2.599 billion of non-residential alteration work in the 12 months to April this year, down by $131 million (-4.8%) from the April year peak of $2.73b in 2025.

However, the amount of non-residential alteration work consented in the April 2026 year was still the second highest ever in an April year, the data goes back to 1991, and accounted for 29.3% of the value all non-residential building work consented in that period.

While non-residential alteration work may be more resilient than residential work, it may also be in a slow decline.

As a percentage of the value of all non-residential building work, alteration work has steadily declined from a peak of more than 50% in the early 1990s, to under a third in the last few years.