Usually you do not need a full building consent. But across most of Wellington the structural fixings that hold the array to your roof have to be designed or approved by a Chartered Professional Engineer, and that is a wind zone question rather than a solar one. On the council’s own maps, roughly four addresses in five sit above the line where the simple exemption stops.
Where the exemption actually stops
Schedule 1 of the Building Act carries an exemption, 28D, that lets a roof-mounted array go up with no building consent at all. It has two conditions, and both have to hold:
- Size. The array, or all the arrays together on each independent roof structure, must not exceed 40 square metres.
- Wind. Either the design wind speed does not exceed 44 metres per second, calculated using Verification Method B1/VM1, or the site is in a wind zone no greater than high under Acceptable Solution B1/AS1.
Meet both and no building consent is needed. The same guidance also asks for the array to sit at least 600 millimetres clear of roof edges and gutters, and not to extend past the roofline.
The size condition is rarely the binding one on a house. The wind condition usually is.
Why most of Wellington sits above that line
Wellington City Council publishes its wind zone maps as open data. Summing the mapped areas by zone gives this:
| Wind zone | Share | Exemption 28D? |
|---|---|---|
| Extra High | 33.8% | No |
| Very High | 31.4% | No |
| Specific Engineering Design | 17.5% | No |
| High | 11.3% | Yes |
| Medium | 6.0% | Yes |
82.7 percent sits above “high”. Only about one address in six is in the zone where the straightforward path applies. Specific Engineering Design is the strictest of these: it means the site falls outside the scope of the standard tables altogether.
Two caveats. That share covers the land the council classifies and excludes a large area its dataset leaves unlabelled, and it is Wellington City only. The Kāpiti Coast, Porirua and the Hutt are separate councils with their own maps, so check the one that covers your address.
What applies above the threshold
Above 40 square metres, or above the wind threshold, the work falls under exemption 48A instead. That is still an exemption rather than an automatic consent, but it comes with a condition. MBIE’s guidance puts it plainly: the structural fixings attaching the array to the roof have to be designed or approved by a Chartered Professional Engineer, or use a pre-engineered kitset carrying a Chartered Professional Engineer’s sign-off.
If neither of those covers the job, a building consent is required. MBIE’s own worked example is a 30 square metre array in a zone greater than high, where the owner has no engineered design and no signed-off kitset: consent needed.
In practice this is routine work for an installer who does it every week. It is not a reason to avoid solar and it is not usually a delay. It is simply a step that exists here and does not exist in a low wind zone.
Building consent is not the same as electrical sign-off
These get confused constantly, so it is worth separating them.
- The building side is structural. It is about the fixings, the roof and the wind, and it is what exemptions 28D and 48A deal with.
- The electrical side is separate and applies no matter what your wind zone is. The array is installed to AS/NZS 5033, the inverter is connected to the grid under AS/NZS 4777, the work is done by EWRB registered electricians, and the job is issued with an electrical certificate of compliance. Your lines company also has to approve the connection before the system can export.
A quote that is silent on either side is incomplete. Ours covers both.
What to ask whoever quotes you
Five questions that will tell you quickly whether an installer has actually assessed your address rather than assumed it:
- Which wind zone have you assessed this address as, and from whose map?
- Will the array exceed 40 square metres on any one roof structure?
- Are the fixings engineered for this site, or a pre-engineered kitset with a Chartered Professional Engineer’s sign-off?
- If a building consent is needed, who lodges it and who pays for it?
- Will I get an electrical certificate of compliance, and who arranges the lines company connection?
Common questions
Do I need a building consent for solar panels in New Zealand?
Often not. A roof array under 40 square metres in a wind zone no greater than high is exempt under Schedule 1. Above either threshold the fixings need a Chartered Professional Engineer’s design or sign-off, and without that a consent is required.
How do I find out my wind zone?
Your territorial authority publishes wind zone maps. Wellington City Council’s are open data. Neighbouring councils publish their own, and an installer should be checking the map for your specific address rather than applying a citywide assumption.
Does this apply on the Kāpiti Coast?
The same national rules apply everywhere in New Zealand. The wind zone itself is local, and Kāpiti is assessed against Kāpiti Coast District Council’s maps rather than Wellington City’s, so the answer for an exposed coastal site and a sheltered inland one can differ.
What if my array is under 40 square metres?
Size alone is not enough. Both conditions have to hold, so a small array on an Extra High wind zone site still falls outside exemption 28D.
Does the wind reduce how much power I generate?
No. Wind affects how the array is fixed down, not its output. For what the region actually generates, see how much sun Wellington gets for solar.
We assess the wind zone for your address as part of quoting, and the quote sets out how the fixings are covered before you commit. Site visits and quotes are free.
Sources: consent rules from MBIE, building work that does not require a building consent, edition 6, January 2026, sections 14.3 and 14.4. Wind zones from Wellington City Council open data. Rules and maps change, and this is general information rather than advice on your property. Confirm your own address with your council before relying on it.