Concrete Path Thickness NZ: How Thick Does a Path Actually Need to Be?

A pedestrian-only concrete path is normally laid at 75–100 mm. Once a vehicle can touch it, 100 mm is the minimum: that is the figure the NZ Master Concrete Placers Association sets for a domestic driveway, and thickness has to reflect the use. Heavy vehicles need a designed slab, usually 125–150 mm.

That is the short answer on concrete path thickness in NZ, and most guides stop there. The specifications below come from the NZ Master Concrete Placers Association (NZMCPA) *Code of Practice for Concrete Placement of Domestic Driveways*, current as at 2026, with the clause number against each figure so you can check any of it against a quote.

For a path that only ever carries people, 75–100 mm is established New Zealand trade practice. The code's 100 mm minimum is written for domestic driveways, so 75 mm is not a code figure and should never be treated as one. It is what the trade builds a garden path at when nothing with an engine is going near it.

When 75 mm is fine

A straight garden path, a side access run down the fence line, a bin run, a clothesline path, or the track to a shed door. Foot traffic only, on ground that drains, with control joints at close centres.

Trade guidance supports this at the thinner end: a 75 mm path with joints at 3 m centres or closer carries little cracking risk, and either no mesh or a light 668 mesh is appropriate. Our concrete footpaths work sits in this range for most residential jobs.

When to go to 100 mm

Move up to 100 mm for wheelbarrow and ride-on mower routes, because small wheels concentrate a lot of weight into a very small contact patch. Go to 100 mm over reactive clay, which most of Auckland sits on.

Go to 100 mm for any path a car could conceivably reverse across, including anything inside a driveway's turning arc. If a path will carry a load a person could not carry by hand, it is no longer a path in specification terms.

The Basis column matters. Where a row says trade practice, that is what competent builders do, not a published minimum you can hold anyone to. Where it says NZMCPA, that is the code minimum for domestic work in New Zealand.

Mesh is commonly paired to thickness in the trade as F62 at 100 mm, F72 at 125 mm and F82 at 150 mm. Treat that as typical practice rather than a standard, and let the slab designer confirm it on anything carrying a heavy vehicle.

It comes down to how the weight arrives. A person is a spread load across a wide contact area. A car wheel is a concentrated load pressed into a patch about the size of a dinner plate, applied thousands of times over the life of the slab.

Concrete is very strong in compression and weak in bending. A point load makes the slab bend locally, and bending is what breaks it. The extra 25 mm and the steel mesh both exist to deal with that.

The code sets the principle plainly: the minimum is 100 mm, thickness must reflect the use, and trucks or other heavy vehicles require a designed slab for the additional loading (cl. 2.1). A designed slab means an engineer sets the thickness and the steel for that site and that vehicle. Our new driveway installation work starts from the 100 mm figure and goes up.

Thickness is only one of seven numbers that decide whether a path lasts:

• Base depth and material
• Concrete strength in MPa
• Mesh size
• Mesh position within the slab
• Fall
• Control joint spacing, depth and timing
• Cure duration

Get the thickness right and any one of those wrong, and the path still fails. Here is what each of them should be.

Strip out topsoil, vegetation and any weak or soft material, then replace it with 100 mm of Gap 20 or similar, placed and consolidated (cl. 1.2). That is the single most commonly skipped item on a cheap quote.

It matters more than most people expect, and the reason goes back to bending. A slab over a soft spot has nothing under it to push back, so it bridges the gap and flexes. Most cracked and sunken paths in Auckland are a base problem rather than a thickness problem.

The code also sets a surface tolerance of ±10 mm from an established datum, string lined in several directions (cl. 2.1–2.2). If a quote does not name the basecourse depth and material, that is the first line to ask about.

Specify 20 MPa or stronger (cl. 2.2). Concrete production in New Zealand is governed by NZS 3104:2003, so strength is a property of the mix you order, not something the crew adjusts on site.

Two things you can check on the day:

• Water. The NZS 3104 rule allows 10 litres per m³ on site (cl. 2.3). Water added beyond that to make placing easier weakens the finished slab permanently. If a hose is running into the chute, ask why.
• Vibration. The code is emphatic that all concrete must be vibrated, using immersion vibrators, vibrating screeds, or floats with mini-vibrators (cl. 3.4.1–3.4.3). Unvibrated concrete has voids left inside it.

Larger pumps able to handle 19 mm stone also produce a mix with less shrinkage and fewer cracks than one cut down to suit a small pump (cl. 3.2), which is worth asking about where access is tight.

For a free on-site quote anywhere in Auckland, call 09 977 9966.

Yes at 100 mm. At 75 mm it is optional where the joints are close together. The code specifies 665 or 668 mesh (cl. 5.1–5.2), with sheets overlapped and tied, internal corners reinforced, and no cutting of every second bar.

Polypropylene or cellulose fibre is worth considering alongside the mesh to control plastic cracking in the first hours after the pour (cl. 5.1).

Where the mesh has to sit

Within the top third of the finished slab, on chairs sized to that slab thickness (cl. 5.3). Mesh dropped onto the base and left there is doing nothing at all.

Shrinkage cracks open at the top surface, so that is where the steel has to be to hold them closed. The detail becomes invisible the moment the pour starts, which is a good reason to be on site when the chairs go in.

Steel mesh does not make a thin slab strong

This is the expensive misunderstanding, and the code says it directly: steel mesh does not increase the load capacity of the slab. It is crack control. It holds shrinkage cracks tightly closed so they stay hairline instead of opening into something you notice from the kitchen window.

Mesh does not let anyone pour thinner than the use requires. If a quote offers a thinner slab "but with mesh in it", that is not a trade-off. It is just a thinner slab.

Three more numbers, and all three are things you can watch happen on your own job.

Fall

A minimum of 1:100, which is 10 mm of fall per metre (cl. 2.2, 3.3). Water has to run off the path and away from the house rather than pond on it.

In Auckland this is a working requirement rather than a formality. Where a path has to shed height instead of run flat, concrete steps solve the fall problem better than a steep ramp does.

Control joints

Cut them 24–48 hours after placing, at 3 m centres, to a quarter of the slab depth (cl. 5.2). On a 100 mm slab that is a 25 mm cut.

The quarter-depth cut creates a deliberate weak line through the slab, so the concrete cracks where you chose rather than where it would have chosen. Hand-tooled joints are an alternative, marked out on the formwork before the concrete is confirmed (cl. 5.1).

Curing

Constant water curing for a minimum of four days, or 96 hours, unless another method the code recognises is used (cl. 4.3). Keep pets and people off the slab entirely for the first 12–24 hours (cl. 4.4).

Concrete does not dry, it cures, which is a chemical reaction that needs water to continue. Losing that water early costs strength that never comes back.

Much of Auckland sits on reactive clay that swells when it is wet and shrinks when it dries out. That seasonal movement is exactly the bending load a slab is weakest against, which is why the 100 mm consolidated basecourse matters more here than an extra 25 mm of concrete would.

Auckland's wet winters make the fall specification earn its place too. Water sitting on a path finds the joints, works into the base beneath, and softens the material the slab depends on. Heavier clay is common through West Auckland around Henderson and Te Atatū, sloped sections are the norm across much of the North Shore, and coastal exposure adds its own wear at the Bays.

One planning note before you pour a lot of new hard surface: Auckland Council administers the Auckland Unitary Plan, which sets impervious surface and stormwater rules for a site. Where a path crosses the berm or joins the road, Auckland Transport approves the vehicle crossing, while resource and building consents remain with Auckland Council. The two bodies run separate processes, and one approval does not cover the other. Our guide to West Auckland council requirements for driveways covers the impervious surface and drainage side in detail.

The NZMCPA code is blunt about this, and it is worth quoting. "Concrete can crack. It is not possible to guarantee the absence of concrete cracking, regardless of processes and placing systems employed."

Everything in this article reduces the risk and controls where cracks appear. None of it eliminates them, and anyone promising otherwise is telling you something the industry's own code will not.

Two related points from the code prevent a bad conversation later. Colour consistency, surface texture and flatness will vary across a slab, and those variances are not grounds for rejection. Colour swatches and samples are indicative only.

On finish: hard trowelling produces a smooth surface that is genuinely slippery outdoors when wet, so broom and sponge finishes are almost always the right call on a path. Where an existing path has already cracked, concrete crack repair is often a better first step than replacement.

Plain broom-finish concrete in Auckland runs roughly $90–$160/m², GST inclusive, depending on access, site preparation and how much spoil has to be carted away. Decorative finishes such as exposed aggregate, coloured or stamped concrete sit at roughly $150–$250/m² on the same basis.

Watch the GST basis when you compare quotes. Trade quotes are often written plus GST while consumer quotes are usually GST inclusive, and that difference alone moves a price by 15%. The figures above are GST inclusive.

Base prices normally exclude earthworks and decorative finishes, so check what a quote includes before comparing two of them. Narrow paths also tend to price at or above driveway rates per square metre, because setup, formwork and minimum charges spread across a much smaller area.

On thickness specifically: going from 75 mm to 100 mm is a third more concrete over the same area, before any other change. That is the arithmetic behind a thicker quote, and you can apply it to your own square metreage. For the vehicle side, see what a concrete driveway costs in New Zealand. Every figure here is general Auckland guidance, and a site visit confirms the number for a specific job.

A quote that names all seven is from someone who intends to do all seven.

Measure the area, pick your row from the thickness table based on what will actually travel over the path, then ask for the seven specifications in writing before you sign anything. A contractor who can answer all seven off the top of their head is one who pours to the code.

To have the numbers checked against your own site, call 09 977 9966 or email [email protected] for a free on-site quote anywhere in Auckland.

*Specifications in this guide are drawn from the NZ Master Concrete Placers Association Code of Practice for Concrete Placement of Domestic Driveways, which references NZS 3104:2003, NZS 3114:1987 and NZS 3109:1997. CCANZ Information Bulletin IB80, Residential Concrete Driveways and Paths, covers the same ground in more detail.*