Ten Years of Rubber Mats on a Waikato Dairy Yard

The Gist: Foster and Sam Kalma have fitted out two milking yards with Numat rubber. The mats bought in 2019 are still on the farm, doing a second job.

Most farm infrastructure gets bought once and judged once. Rubber matting is different, because the only honest test is what it looks like after a decade. Amlak Ltd has been a Numat customer since July 2016, and the mats bought in 2019 are still in service today.

Sam Kalma contract milks the family farm at Waitoa, off State Highway 27. The block runs back roughly two kilometres from the road, and Sam checks stock by drone rather than walking every paddock. It is a high input system, which means the cows carry a lot of feed and spend a lot of the day standing on concrete.

"I've been contract milking here for two years. It's the family dairy farm, and I'm just continuing the family tradition of milking cows."
Sam Kalma
Sam Kalma
Amlak Farm, Waitoa

Watch: Sam Kalma on ten years of Numat mats

The lameness problem

Before matting went down, around 15 percent of the herd was walking lame.

“We were facing some lameness issues with the cows. I think we had 15 percent of the herd lame, previously, before we put the mats down.”

There was not much choice about the fix. A high input system keeps cows on concrete for hours at a time, and a concrete yard is a concrete yard.

What lameness actually costs

Sam is honest that he has never put a figure on it, which is the reason the sums rarely get done on any farm.

"It's worth having a research into lameness opportunity cost, and how much you're losing in that area, because theoretically it pays for itself pretty quick."
Sam Kalma
Sam Kalma
Amlak Farm, Waitoa

DairyNZ has done that work. The organisation estimates the average cost of a single case of lameness at between $300 and $800, with the range depending on lesion type, severity, time of season, and the cow’s lameness history. The biggest impact falls on reproductive performance, since cows that go lame soon after calving are less likely to get in calf. DairyNZ Lameness Cost

Run that against your own herd and your own lameness percentage before you look at a single quote.

The first fit-out, 2019

The original call was Foster Kalma’s, made before Sam started contract milking. Sam inherited the mats along with the job, and later put his own name to the same decision.

In November 2019 Numat supplied and installed 430 Legend Interlock mats, 25mm thick, across roughly 423 square metres of yard. Those mats stayed down for close to six years.

How the relationship started

Sam is blunt about how Numat got the business in the first place.

"It probably just comes down to the salesman. These companies usually have pretty aggressive salesmen that come in your gateway and try sell you things, and they were the ones who managed to catch our business."
Sam Kalma
Sam Kalma
Amlak Farm, Waitoa

The rep on that first job was Anthony Garton, and he has been on the account ever since. A decade of knowing a farm, its yard, its concrete and its cows is worth more than any spec sheet. Anthony still looks after rubber matting for Numat across the North Island.

The season that proved it

In 2023 Amlak put in a new yard. The build finished right on calving, which left no window to lay matting before the cows came in. That gave Sam something almost no farm ever gets, which is a clean control season. Same herd, same system, same management, bare concrete underfoot.

“For one season we ran the yard just with bare concrete, and our lameness shot up a fair bit because of that. And with the new concrete surface, it can hurt the cow’s hoof a bit as well.”

He did not wait until the end of the season to make the call. By halfway through, the plan was already made to mat the yard at the next dry off. Having farmed on the old mats, he knew exactly what he was buying.

The second fit-out, 2025

In September 2025 Numat supplied and installed 505 Kura Interlock mats, 25mm thick, covering roughly 511 square metres of the new yard.

The job moved quickly. Deal closed 9 September, mats on site and installed by mid October. Roughly six weeks from a signed deal to a yard the cows could walk on. Numat works to the farm’s calendar, not the other way round, so the milking keeps running while the mats go down.

The part most farms never see

Here is what separates a matting purchase from a matting investment. When the old Legend mats came up off the original yard, they were not scrap.

“When we put the new yard in, we had a whole lot of old rubber matting from Numat that still had a lot of life in it, so we ended up putting it on the feed pad. And that covered about half the feed pad, and we put new stuff down on the yard. And that gives us most of our concrete area covered in mats now.”

Six years on the yard, lifted, relaid, and still working on the feed pad today. One purchase, two locations, seven years of service and counting.

A wet weather option

The first thing Sam mentioned about the mats was not lameness. It was what they let him do with a wet paddock.

"It's given us a bit of an opportunity to stand them off overnight when it's rainy weather."
Sam Kalma
Sam Kalma
Amlak Farm, Waitoa

Cows on rubber overnight are cows that are not pugging pasture. That is a management lever he did not have on bare concrete, and it costs nothing to use.

Day to day on the yard

The mats earn their keep where the yard fights the cows. There is a step up between the feed pad and the yard that has always been a difficult spot, and a cow that goes down on the slippery bit now has somewhere decent to land. A cow that gets herself back up is a cow that stays in the herd.

The most common objection to matting is that it adds work to the morning. Sam has run both setups, hose on the old yard and a dung buster on the new one.

“It’s been pretty effortless, really. On the new yard we put a dung buster in, and that pretty much does the job for us. It’s been easy as.”

On a dung buster yard, the mats add nothing to the job.

Sam's advice to other farmers

He is straight about who should not spend the money.

“A lot of people don’t have a lameness problem. They’ll be down at five percent, or three percent lameness per season. And if you don’t have the problem, then it’s not worth trying to solve the problem.”

But where the problem is real, he does not hedge. When it comes to yards, matting is the answer.

Anthony Garton looks after rubber matting for Numat across the North Island. Call him on 021 824 243 or ring Numat on 0800 686 119. He will walk your yard with you and tell you straight if matting stacks up on your numbers.

Thanks for opening the gate

Our thanks to Sam and the Kalma family for opening the farm to us and giving up time on a working day.

Sam gave us his honest read on the mats, including the parts that are not a sales pitch. He was clear that plenty of farms do not have a lameness problem and should not go spending money solving one. That kind of straight talk, and ten years of knowing what has actually worked on the farm, is worth more to another farmer than anything we could write ourselves.

Turn your yard into a stand-off area

A matted yard is a stand-off area you already own. Somewhere to hold cows overnight through a wet spell, off the paddock and off bare concrete.

Send us your yard details and we will come back with an honest answer on whether matting is worth it for you.