Roofing in New Zealand

New Zealand is a country of light timber houses built for a temperate, often wet and windy climate and frequent earthquakes. Māori buildings were lashed timber frames thatched with plant materials; colonial settlers moved from raupō thatch and timber shakes to corrugated iron within a few decades; and pre-painted profiled steel is now the most common roof on new houses.

Climate and hazards

Rainfall is high in many regions and winds are strong, especially in places such as Wellington, so fixing schedules and flashings matter. Light roofs are favoured partly because they reduce earthquake forces. Coastal sites expose roofs to salt spray, making coating durability and fastener corrosion resistance important, and southern and alpine areas add snow load.

Roofing history

Māori building. Before European contact Māori had no nails and wove or lashed their buildings together from forest and swamp materials. Timber was used for posts, ridge poles and outer walls, tree-fern slabs for walls, and roofs were thatched with rushes, bark or toetoe tied to battens, often of mānuka. In the whare, the roof and walls extended forward to form a porch, a form still seen in the wharenui, whose ridge beam, rafters and bargeboards represent the body of an ancestor. Framing members were bound with lashings (mīmiro); after steel tools arrived, meeting houses grew larger from the 1840s and nails gradually entered the woodwork.

Raupō and early settler houses. Early settler huts were thatched with raupō, toetoe, flax, fern or tōtara bark. Raupō houses were cheap, quick to build and close to Māori housing, but highly flammable. The Raupo Houses Ordinance of 3 March 1842, New Zealand's first building legislation, allowed the governor to impose an annual £20 tax on thatched or raupō buildings in towns. After a fire starting in a raupō bakehouse destroyed about 57 buildings in Wellington in November 1842, the ordinance was applied there in 1843. Even so, an 1849 census of the Auckland area found raupō made up almost a third of European housing; by 1878 only 0.55% of non-Māori dwellings were raupō.

Shakes, shingles, iron and tile. Many wooden houses were roofed with split shakes and later sawn shingles, and also with fern fronds, bark sheets, bitumen-coated fabric, canvas or long boards. From the mid-1800s until about 1915, roofs were typically pitched at 30-45 degrees, steeper in the south to shed snow. Iron nails were scarce and costly in the 1840s and 1850s, and cheaper nails from the 1860s changed construction. Wooden shingles were eventually outlawed in towns as a fire hazard and replaced by corrugated iron; slate became more common late in the 19th century, and Marseille-pattern clay tiles, imported from 1899, displaced slate between the 1890s and 1920s. Asbestos-cement sheet was widely used until the 1980s.

The leaky building crisis. Many timber-framed homes built between 1988 and 2004 were not weathertight. Contributing factors included face-sealed claddings, untreated radiata pine framing permitted from 1995, and "Mediterranean" designs with flat or complex roofs, minimal eaves, parapets and balconies. A 2009 PwC estimate put repairs at about NZ$11.3 billion for 42,000 buildings. See leaky homes crisis.

Traditional and vernacular roofs

• Wharenui (meeting house): gabled, with a deep porch; tāhuhu (ridge beam) and heke (rafters) as backbone and ribs.
• Whare raupō: houses thatched with raupō, used by Māori and early settlers.
• Colonial cottage: steep gabled roof in shakes, shingles or iron.

Roofing today

The BRANZ New Dwellings Survey for 2022 found that sheet metal covered 64.6% of new houses, tiles (metal and concrete) 25.7% and other materials, mostly shingles and membranes, 9.7%. Common coverings include corrugated and trapezoidal pre-painted steel, stone-coated steel tiles, concrete and clay tiles, and butyl, EPDM, TPO or torch-on bitumen membranes on low-slope roofs.

Codes, standards and regulation

Roofs must meet the New Zealand Building Code, notably Clause B1 (structure, referencing AS/NZS 1170 loadings) and Clause E2 External Moisture, whose Acceptable Solution E2/AS1 reached its fourth edition in July 2025. The leaky building crisis led to the Building Act 2004, a return to treated framing under NZS 3602:2003 and much stricter flashing and junction details. Roofing on homes is restricted building work: it must be done or supervised by a Licensed Building Practitioner, whose roofing licence has classes including profiled metal, metal tile, membrane, shingles, torch-on and liquid roofing.

Industry

New Zealand Metal Roofing Manufacturers (NZMRM) publishes the NZ Metal Roof and Wall Cladding Code of Practice (v26.09, September 2026). The Roofing Association of New Zealand represents contractors, and BRANZ carries out independent building research.

Notable roofs

Carved meeting houses on marae across the country hold special significance in Māori culture; the New Zealand Māori Arts and Crafts Institute, established under a 1963 Act, has built or restored more than 40 marae.

Local roofing terms

• Tāhuhu: ridge beam. Heke: rafters. Maihi: bargeboards.
• Raupō: bulrush used for thatch and walls.
• Toetoe: native grass used for thatch.

Sources and gaps

The national census does not publish roof materials; the BRANZ figures cover new houses only.