Building a basic post-and-rail fence is one of the more achievable DIY projects for a NZ homeowner. With the right tools, decent timber, and a bit of patience, you can have a tidy boundary or paddock fence up over a weekend. Here's a rundown of everything you'll need before you start digging.
Planning Before You Pick Up a Tool
Before you buy or hire anything, take a moment to plan your fence line. Measure the total length, note any slopes or changes in ground level, and mark out your post positions — typically 1.8 m to 2.4 m apart for a standard post-and-rail fence, though this varies with timber size and rail span. Check with your local council whether a building consent is required; most residential boundary fences under 2 m high are exempt under Schedule 1 of the Building Act, but it's always worth confirming. You can find guidance on consent exemptions at MBIE Building Performance.
Also check for underground services (power, gas, water, telecoms) before you dig. Call Dial Before You Dig (0800 248 344) — it's free and could save your life.
Essential Tools for the Job
Marking Out and Measuring
- Tape measure (at least 10 m) — for spacing posts accurately
- Builder's line and line pins — to keep your fence line straight
- Spray paint or pegs — to mark post hole positions
- Spirit level (1.2 m or longer) — critical for plumb posts
- String line — helps set consistent post heights across uneven ground
Digging Post Holes
This is the most labour-intensive part. Your options:
- Manual post-hole digger (clamshell digger) — fine for a few holes in soft ground
- Crowbar or digging bar — essential for breaking up hard or rocky NZ soils
- Petrol or electric post-hole auger — strongly recommended for longer runs; available for hire from most tool hire shops and from Bunnings or Mitre 10
As a general rule, posts should be set to a depth of at least one-third of their total length — so a 1.8 m post needs roughly 600 mm in the ground. In areas with loose or sandy soil, go deeper.
Setting Posts
- Wheelbarrow and mixing hoe — for mixing concrete (or use rapid-set bags)
- Bucket — for water
- Tamping rod or offcut timber — to consolidate concrete around the post
- Temporary bracing timber and clamps — to hold posts plumb while concrete sets
Most fencers use a bagged rapid-set concrete (available from PlaceMakers, Bunnings, or Mitre 10) for post setting — it's straightforward and sets firm within an hour or two.
Cutting Timber
- Circular saw or drop saw (mitre saw) — for cutting rails to length cleanly and safely
- Hand saw — useful for trimming in tight spots
- Pencil and square — for marking accurate cut lines
Always wear eye protection and hearing protection when using power saws. Follow the safety guidelines at WorkSafe NZ.
Fixing Rails to Posts
- Hammer (a 750 g to 1 kg framing hammer works well) — for nailing rails
- Cordless drill/driver — for screwing rails if you prefer screws over nails
- Galvanised framing nails or structural screws — essential in NZ's variable climate; plain steel fixings will rust quickly, especially near the coast
- Nail punch — for setting nail heads flush
| Fixing Method | Pros | Cons |
|---|---|---|
| Galvanised nails | Fast, traditional, cheap | Harder to remove if you make a mistake |
| Structural screws | Strong, removable, neat | Slower, costs more |
Safety Gear
Don't skip this. At minimum you'll need:
- Safety glasses or goggles
- Steel-capped boots
- Work gloves
- Hearing protection (when using power tools)
- Sunscreen and a hat — NZ UV is no joke
Choosing the Right Timber
For ground contact (posts), always use H5-treated timber — this is the NZ standard for timber in direct ground contact. For rails above ground, H3.2-treated is the minimum. Untreated or under-treated timber will rot quickly in NZ conditions. Look for the treatment mark on the timber or ask your supplier. BRANZ has useful guidance on timber durability and treatment classes.
Hiring vs Buying Tools
If this is a one-off project, hiring a post-hole auger makes a lot of sense — buying one is expensive and you may never use it again. Most tool hire centres stock them, and both Bunnings and Mitre 10 offer tool hire services at many locations. For hand tools like hammers, levels, and tape measures, it's worth owning good quality ones as you'll use them on future projects.
When to Call a Professional
Post-and-rail fencing is generally DIY-friendly and doesn't involve restricted building work. However, consider hiring a qualified fencer if:
- Your site has significant slope, rock, or very hard ground
- You're fencing a long boundary and need it done efficiently
- The fence is on a shared boundary (neighbour disputes can get complicated)
- You're unsure about consent requirements or boundary locations — always get a survey if in doubt
A professional fencer will have the right machinery, experience with NZ soils, and can get the job done faster than most DIYers. You can find qualified local fencers on tradedirectory.co.nz.
