Re-roofing a villaKeep the look. Upgrade everything you can't see.

What villa roofs are usually made of

Villas were the common house in early 20th century Auckland, before Californian bungalows and Spanish mission homes took over in the 1920s, Auckland Council's history of the city's housing says. In Dunedin, Heritage New Zealand says most of the historic housing stock is villas from the 1870s on.

Most of them wear sheet metal. In BRANZ's survey of Christchurch houses, the pre-1930 homes were almost all sheet roofed: 37 sheet roofs against 2 heavy tile. A typical listed Dunedin villa has a steeply pitched gable roof of corrugated iron and brick chimneys with corbelled tops.

Keeping the look: profile, curves and details

Corrugate is the obvious choice. Dimond calls it a firm favourite with Kiwis because of its classic look. If you want something closer to the old iron, Roofing Industries describes its True Oak corrugate as a return to the original, deeper, rounder corrugate profile.

Curved verandah roofs can be matched. Metalcraft Roofing, for example, offers bullnose, drape and spring curving for its corrugate. Ask the roofer how they'll handle the curve and the junction with the main roof.

Watch the pitch on shallow verandahs and lean-tos. Standard corrugate generally needs at least 8 degrees, or 10 when sheets are end-lapped, while True Oak is rated down to 4. If part of your roof is flatter than the profile allows, the roofer needs to say how they'll deal with it.

Photograph the ridge, barge flashings, finials and spouting (gutters) before work starts, so anything that's replaced can be matched rather than simplified.

Upgrading what you can't see

Underlay is the big one. E2/AS1, the Building Code's acceptable solution for weathertightness, says all profiled metal longrun roofing must have a roof underlay, and that metal roofs need paper-based underlays. Kingspan Thermakraft says that since 1 July 2025 its synthetic absorbent underlays are for lined buildings only, and cites the metal roofing Code of Practice as saying underlay isn't required on unlined structures such as many verandahs.

Near the coast, the metal and fixings matter more. Homes within 500 m of the coast, including harbours, are in exposure zone D, where structural fixings other than nails and screws must be grade 304 stainless steel or better. E2/AS1 only accepts unpainted AZ150 coated steel on exposed roofs in zones B and C, and New Zealand Steel asks owners within 100 metres of salt water to contact it to confirm their COLORSTEEL warranty. That covers plenty of villas in places like Devonport, Stanley Point and Herne Bay.

With the roof off, it's also the easiest time to look at ceiling insulation and ventilation. Our guide to roof insulation and underlay covers what's worth doing.

Character areas, heritage and consent

For the building consent, a straight swap is the easy path. Wairoa District Council's example of work that doesn't need consent is new corrugated iron replacing old corrugated iron with no change to the purlins, unless the cladding failed within 15 years. Changing the purlins does need consent. Going heavier, from corrugated iron to concrete tiles, needs consent in MBIE's guidance too.

The district plan is a separate question. In Auckland's Special Character Areas Overlay (Residential), restoration and repair is a permitted activity, external alterations need resource consent, and in areas such as Isthmus A demolishing 30% or more of wall elevations and roof areas needs resource consent as well. In the Historic Heritage Overlay, maintenance and repair is only permitted with the same materials (or the closest equivalent), the same design, texture and form, and no sand or water-blasting or scaffolding fixed to the building.

Wellington has its own character precincts, which make it hard to demolish pre-1930s homes, now trimmed to 86 hectares of the best-preserved streets. If your villa was built before 1900, Heritage New Zealand says works that may modify or destroy a pre-1900 structure need an archaeological authority, even when other consents are granted. Our building consent guide goes through the consent side in detail.

Deal with the chimney while the scaffold is up

Most villas are well before 1970, and the Natural Hazards Commission says homes built before then most likely have unreinforced brick or masonry chimneys. Its safest option is removing the chimney from the top all the way down to floor level, or, if you still use the fire, replacing the part above the roof with a lighter metal flue.

A re-roof is the sensible moment to do it, because the access is already there. In a character area, check whether taking it off counts as an external alteration first. Our chimney guide has the detail.