Yes, in most cases you can build a small freestanding brick letterbox yourself in New Zealand — no licence is required for basic bricklaying, and a modest letterbox structure generally falls within the building consent exemptions under Schedule 1 of the Building Act 2004. That said, there are a few important rules around size, foundation, and location that you should understand before you mix your first batch of mortar.
Do You Need a Building Consent?
For a small freestanding letterbox, a building consent is generally not required under Schedule 1 of the Building Act. However, the exemption applies only when the structure is low-risk and of limited size. As a rule of thumb, a single-skin brick letterbox up to around 1 metre tall and not attached to any other structure is unlikely to need consent.
That said, rules can vary between councils and depend on your specific site. Always check with your local council before you start — this is especially important if your property is in a heritage overlay, a special character zone, or subject to a resource consent condition. You can find general guidance on exemptions at MBIE Building Performance.
What You'll Need
Here's a basic materials list for a standard freestanding brick letterbox:
| Item | Notes |
|---|---|
| Bricks | Standard NZ clay or concrete bricks |
| Mortar mix | Pre-mixed or cement + sand (1:4 ratio) |
| Concrete | For the footing/foundation |
| Reinforcing rod (rebar) | Optional but recommended for stability |
| DPC (damp-proof course) | Plastic strip above footing to prevent rising damp |
| Letterbox insert | Galvanised or stainless steel flap/box |
| Trowel, spirit level, string line | Essential hand tools |
| Jointing tool or dowel | For finishing mortar joints |
You can find bricks, mortar, and tools at Bunnings, Mitre 10, or PlaceMakers.
Step-by-Step: Building Your Brick Letterbox
1. Plan Your Design and Location
Decide on the size and position. Your letterbox must comply with NZ Post delivery requirements — it should be accessible from the footpath and at a comfortable height (typically the opening sits around 900–1200 mm above ground). Check your local council's rules on placement near the boundary or road.
2. Dig and Pour the Footing
Excavate a footing hole at least 300 mm deep and wider than your letterbox footprint. Pour a concrete footing and allow it to cure for at least 24–48 hours before laying bricks. A solid footing is critical — without it, your letterbox will crack or lean over time, especially in areas with clay soils that shrink and swell.
3. Lay a Damp-Proof Course
Once the footing has cured, lay a DPC strip (a thin plastic membrane) on top before you start bricklaying. This stops moisture wicking up from the ground into the brickwork — an important step in New Zealand's often wet conditions.
4. Lay Your Bricks
Mix mortar to a smooth, workable consistency. Lay bricks in a running bond pattern (each brick centred over the joint below) for strength. Use a spirit level constantly — both horizontally and vertically. Keep mortar joints consistent at around 10 mm. If you're inserting a rebar for extra stability, set it in the footing and build the brickwork around it.
5. Install the Letterbox Insert
Leave an appropriately sized opening as you build up the courses. Most homeowners use a pre-made galvanised steel letterbox insert, which slots into the opening and is mortared or screwed in place.
6. Finish and Seal
Once the mortar has set (allow at least 24 hours), finish the joints with a jointing tool for a neat, weathertight result. You may choose to apply a masonry sealer to protect the brickwork from NZ's UV and rain exposure, particularly in coastal or high-rainfall areas.
Tips for a Neat, Long-Lasting Result
- Use a string line between corner profiles to keep your courses straight.
- Don't lay bricks in the rain or when temperatures are below 5°C — mortar won't cure properly.
- Keep bricks damp before laying in hot weather to prevent them drawing moisture out of the mortar too quickly.
- Match your brick type and colour to your home's existing brickwork if possible — it looks far more intentional.
- For coastal properties, choose salt-resistant bricks and mortar to prevent spalling and efflorescence.
BRANZ has excellent technical guidance on masonry construction and weathertightness if you want to dig deeper into best practice.
When to Call a Professional
While a simple brick letterbox is a manageable DIY project for a patient homeowner, consider hiring a qualified bricklayer if:
- You want a larger or more complex structure (e.g., with pillars, a gate, or integrated lighting).
- Your site has difficult ground conditions, a slope, or poor drainage.
- You're unsure about footing depth or structural requirements.
- The letterbox is close to a boundary, retaining wall, or underground services.
If your letterbox design includes electrical wiring (e.g., for a light or intercom), that work must be carried out by a registered electrician — this is restricted work under the Electricity Act. Check the Electrical Workers Registration Board for what's permitted.
You can find experienced, local bricklayers and stonemasons on tradedirectory.co.nz who can quote on the job or give you advice before you start.
Sources & Further Reading
- MBIE Building Performance – Building consent exemptions
- BRANZ – Masonry and weathertightness guidance
- Bunnings – Bricks, mortar and masonry tools
- Mitre 10 – DIY materials and project guides
- Electrical Workers Registration Board – Restricted electrical work
- Licensed Building Practitioners – When you need an LBP
Licensed Building Practitioner (LBP)
