Building a brick fire pit is a rewarding weekend project that can transform your backyard into a year-round gathering spot. Done correctly, it's safe, durable, and compliant with NZ rules — but there are a few important steps to get right before you light your first fire.
Check Local Rules Before You Start
This is the most important step. In New Zealand, open-air fires are regulated at both national and local council level. Before building anything, you need to:
- Check with your local council about whether open fires are permitted in your area. Many urban and suburban zones have restrictions or outright bans on open burning, particularly in areas with air quality management plans (such as parts of Auckland, Christchurch, and the Waikato).
- Check for fire season restrictions with your regional council or Fire and Emergency New Zealand (FENZ). During dry summer months, open fires may be prohibited entirely.
- Confirm whether a building consent is required. A standalone fire pit is generally a minor garden structure, but if you're building a permanent raised structure over a certain size or attaching it to a deck or dwelling, consent may be needed. Always confirm with your council — don't assume Schedule 1 exemptions apply to your specific situation. See MBIE Building Performance for general guidance on consent exemptions.
Choose the Right Location
Siting your fire pit correctly is critical for safety and neighbourly relations:
- Position the pit at least 3 metres from any structure, fence, overhanging tree, or combustible material. More distance is always better.
- Avoid low-lying spots where wind can swirl unpredictably. A sheltered but open area is ideal.
- Keep the pit away from dry grass or garden mulch, which can catch embers easily — especially relevant in NZ's dry summer conditions.
- Consider prevailing wind direction so smoke doesn't blow toward your home or neighbours.
- Place the pit on a non-combustible surface such as compacted gravel, concrete, or pavers. Never build directly on a timber deck.
Materials: What to Use (and What to Avoid)
Not all bricks are suitable for a fire pit. This is where many DIY projects go wrong.
| Material | Suitable? | Notes |
|---|---|---|
| Fire bricks (refractory bricks) | ✅ Yes — best choice | Designed to withstand repeated high heat cycles |
| Dense engineering bricks | ⚠️ Sometimes | Check manufacturer specs; some tolerate heat reasonably well |
| Standard clay house bricks | ⚠️ Use with caution | Can crack or spall with intense, repeated heat |
| Concrete blocks / pavers | ❌ Avoid for inner lining | Can crack or explode when exposed to high heat |
| Reclaimed bricks (unknown origin) | ❌ Avoid | Unknown composition; unpredictable heat performance |
Fire bricks are available from masonry suppliers and some larger hardware stores. Pair them with refractory mortar (also called fire cement or high-temperature mortar) rather than standard cement mortar, which will crack under heat. Brands like Sika offer high-temperature construction products — check with your local supplier for what's available in NZ.
For the outer decorative wall, standard clay bricks are fine, as they won't be exposed to direct flame.
Step-by-Step Build Guide
1. Prepare the Base
Excavate the area to about 150–200 mm depth. Fill with compacted gravel for drainage, then lay a concrete slab or a double layer of fire bricks as the floor. Good drainage is especially important in NZ's wet winters — a waterlogged base can cause frost heave and cracking.
2. Lay the Inner Fire Brick Ring
Using refractory mortar, lay fire bricks in a circular or square pattern to form the inner lining. A typical backyard fire pit is 600–900 mm in internal diameter. Keep mortar joints tight and consistent — around 10 mm.
3. Build the Outer Wall
Once the inner lining is set, build your decorative outer wall using standard bricks and general-purpose mortar. Leave a small gap (an expansion gap) between the inner and outer walls to allow for heat expansion — this prevents cracking.
4. Allow Full Cure Time
Let all mortar cure for at least 48–72 hours before lighting any fire. For refractory mortar, follow the manufacturer's instructions — some products require a gradual curing burn (a series of small fires) before full use.
5. First Use
Start with a small fire to allow the structure to settle. Check for any cracking after it cools, and repoint with refractory mortar if needed.
Ongoing Safety Tips for NZ Conditions
- Never leave a fire unattended and always have water or a fire extinguisher nearby.
- Check FENZ fire restrictions before every use, especially in summer. Conditions can change quickly in NZ.
- Keep a spark screen or mesh cover on hand to contain embers on windy days.
- Only burn dry, untreated timber. Never burn treated timber, painted wood, rubbish, or green wood — these produce toxic smoke and are illegal to burn in many NZ areas.
- Cover the fire pit when not in use to prevent water pooling, which degrades mortar over time.
When to Call a Professional
If you're planning anything beyond a simple freestanding fire pit — such as a built-in outdoor fireplace, a chimney structure, or a fire feature attached to a pergola or outdoor kitchen — you should engage a qualified bricklayer or stonemason. Complex structures may require building consent and the work of a Licensed Building Practitioner (LBP). A professional will also know your local council's specific requirements.
You can find experienced local bricklayers and stonemasons on tradedirectory.co.nz.
Sources & Further Reading
- MBIE Building Performance — Building Consent Exemptions
- Fire and Emergency New Zealand — Fire Safety
- BRANZ — Building and Construction Research
- Sika NZ — Construction Products
- Licensed Building Practitioners
Licensed Building Practitioner (LBP)
