Splitting fence palings when nailing them is one of the most common frustrations in DIY fencing — but it's almost entirely preventable. With the right nail choice, a bit of preparation, and some simple technique adjustments, you can nail palings cleanly and confidently every time.
Why Palings Split in the First Place
Wood splits when the force of a nail drives timber fibres apart faster than they can flex. Several factors make this worse:
- Nailing too close to the end or edge of a paling, where there's less timber to absorb the stress
- Using nails that are too thick relative to the paling width
- Dry or seasoned hardwood palings, which are less forgiving than green timber
- Blunt or incorrect nail type that wedges rather than pierces
- Knots in the timber, which create weak points and unpredictable grain
Understanding these causes makes the fixes straightforward.
Choose the Right Nails
Nail selection makes a huge difference. For fence palings in New Zealand, keep these points in mind:
- Use hot-dipped galvanised (HDG) nails — these are the standard for exterior timber work and resist corrosion in our damp climate. Stainless steel nails are worth considering near the coast where salt air accelerates rust.
- Avoid plain bright steel nails outdoors — they'll rust and can stain the timber.
- Nail gauge matters: a thinner shank (for example, a 2.8 mm or 3.15 mm diameter nail) displaces less wood than a thick framing nail. Match the nail to the paling thickness.
- Recommended length: as a general guide, nail length should be 2.5 to 3 times the thickness of the paling being fixed. For a typical 100 × 25 mm paling, a 60–75 mm nail is usually appropriate.
- Ring-shank or twisted-shank nails grip better and can allow a slightly thinner shank, reducing splitting risk while still holding firmly.
You'll find a good range of galvanised nails at Bunnings or Mitre 10.
Nail Placement: Where You Nail Matters
Poor placement is the number-one cause of splits. Follow these rules:
- Keep nails at least 25 mm from the end of a paling — closer than this and splitting is almost guaranteed.
- Stay at least 15 mm from the edge (side) of the paling.
- Stagger nails when fixing to rails — don't line them up in a row along the same grain line.
- Avoid knots wherever possible. If you must nail near a knot, pre-drill (see below).
Pre-Drilling: The Most Reliable Fix
Pre-drilling a pilot hole is the single most effective way to prevent splitting, especially in dry, seasoned, or hardwood palings. Use a drill bit that is slightly smaller in diameter than the nail shank — this lets the nail grip while removing the wedging action that causes splits.
For softwood palings (like treated pine, which is common in NZ), pre-drilling is often optional if your nails are correctly sized and placed. For hardwoods or very dry timber, it's strongly recommended.
Blunting the Nail Point
This old tradesperson's trick works surprisingly well: tap the nail point lightly with your hammer to blunt it slightly before driving it in. A blunt point punches through timber fibres rather than wedging them apart, dramatically reducing the chance of a split. It sounds counterintuitive, but it's been standard practice for generations.
Timber Condition and Storage
The condition of your palings before you even pick up a hammer matters:
- Avoid over-dried timber — if palings have been sitting in the sun for weeks, they'll be more brittle. Store timber in the shade and keep it off the ground.
- Check for the appropriate treatment level — in New Zealand, timber used for fencing should meet the relevant hazard class for ground contact or above-ground use. Confirm the correct hazard class with your timber merchant or refer to NZS 3602. Treated pine palings are widely available and are the standard choice. PlaceMakers and most timber merchants stock treated fence palings.
- Slightly damp or green timber is more forgiving to nail than bone-dry stock, though it may shrink slightly as it dries.
Using a Nail Gun
A pneumatic or battery-powered nail gun can actually reduce splitting compared to hand nailing, because the nail is driven in one fast strike with consistent force — less repeated hammer blows means less vibration and stress on the timber. Make sure you're using the correct nails for your gun and that the pressure is set appropriately. Too much pressure can drive the nail head right through the paling face.
A Quick Reference Table
| Problem | Likely Cause | Fix |
|---|---|---|
| Split at end of paling | Nailing too close to end | Keep 25 mm+ from end, pre-drill |
| Split along the grain | Nail too thick or wrong type | Use thinner shank, blunt the tip |
| Split near a knot | Grain disruption at knot | Pre-drill pilot hole |
| Nail head pulling through | Nail too short or head too small | Use correct length, flat-head nail |
| Rust staining on timber | Wrong nail type | Switch to hot-dipped galvanised |
When to Call a Professional
Most fence paling work is straightforward DIY, but there are times to bring in a qualified fencer:
- If your fence is on or near a boundary, you may need to comply with local council rules around height and setbacks — always check with your council before building.
- Retaining walls over a certain height generally require a building consent — check with your local council or MBIE Building Performance for the current threshold and any conditions that apply — check with MBIE Building Performance for guidance on Schedule 1 exemptions.
- If you're unsure about timber treatment requirements or structural rail spacing, a professional fencer will get it right first time.
You can find qualified local fencers on tradedirectory.co.nz.
