For most homes the answer is no. As a general rule, replacing your ageing windows or upgrading to new windows does not require a building consent if there are no structural changes. That covers the great majority of the replacement work we do: the old window comes out, the new one goes into the same opening, and nothing about the structure of the wall changes.
What Counts as No Structural Changes
On a typical window and door replacement the opening stays exactly as it is. We measure the existing opening, make the new joinery to fit it, remove the old window, fit the new one, and flash and seal it. The framing around the opening and the lintel above it are not touched. Swapping tired timber or aluminium windows for new aluminium ones in the same openings is work of that kind.
When to Ask First
If your project does involve structural changes, talk to us and your builder before work starts, and check with your council if you are unsure. The usual examples are a new opening where there was none, or an existing one made wider for a bifold door or a bifold servery window, which needs a properly sized lintel. The official guidance on window and door work is on building.govt.nz under windows and exterior doorways in existing dwellings and outbuildings, and your council's building team can tell you where your own job sits.
The Work Still Has to Be Done Properly
Consent or no consent, all building work has to comply with the Building Code. For new windows and doors that is our job, and in practice it means:
- Weathertightness. The flashings and seals around the new joinery have to keep water out of the wall.
- Safety glass. Glass in doors, beside doors and in low windows must be safety glass, and we specify it wherever the glazing standard requires it.
- Ventilation and light. Habitable rooms must still meet the Building Code for ventilation and natural light, which we take into account when we lay out the opening sashes.
- Pool fencing. If the wall of the house forms part of the barrier around a swimming pool, any change to its doors or windows must still meet the pool barrier rules.
Other Rules Worth Knowing About
Building consent is also separate from planning rules. A heritage overlay, a body corporate or a covenant on a subdivision can each restrict what joinery you fit or what colour it is, even where no building consent is needed. If you live in a character area, a unit title development or a newer subdivision, it is worth a quick check before you choose a colour.
What We Do at the Measure
When we measure for a replacement we look at the existing joinery, the flashings and the sills, and we tell you what the job involves. Where an opening is being widened we work with your builder on the lintel and the programme. OMEGA, whose systems we fabricate, publishes technical documents and building product information for its systems, and as an authorised OMEGA fabricator we can supply them if your council or designer asks.
The Short Version
- Replacing ageing windows, or upgrading to new ones, in the same openings: as a general rule, no building consent.
- Changing the structure, such as a new or bigger opening: talk to us and your builder first, and check with your council if you are unsure.
- Either way, the work must meet the Building Code, and any heritage, body corporate or covenant rules still apply.
Contact Us
Send us a few photos of the windows and the suburb, and we will arrange a free measure and tell you what your job involves. Call 09 278 4089 or use the form below.
