Pet sustainability is a topic the industry would rather not talk about too loudly. The UK has around 11 million pet cats. Each one needs a scratching surface. Most households buy one — often more — per year. That adds up to an enormous volume of product moving through homes and into waste streams, and almost none of the companies making those products have said anything meaningful about what happens to them at end of life.
We've spent a lot of time thinking about this, partly because it's relevant to what Culm is trying to do, and partly because we find it genuinely interesting. Here's an honest look at what the environmental cost of a cat scratcher actually is — and where the meaningful improvements are possible.
What's actually in a standard cat scratcher
Before you can assess the environmental impact, you need to know what you're dealing with. Most cat scratchers on the UK market fall into one of a few categories.
Budget sisal-wrapped posts
Core: MDF or low-grade softwood. Surface: sisal rope, wound tightly and bonded with contact adhesive. Base: often MDF or particleboard, sometimes with a rubber non-slip pad. Finish: the whole unit is typically stapled, glued, and assembled as a single piece. At end of life, the sisal, the MDF, the adhesive, and the rubber are all inseparably bonded together. The whole thing goes to landfill.
Cardboard scratchers
Pressed corrugated cardboard in a plastic or cardboard tray. Better end-of-life story than MDF — cardboard can in principle be recycled, though the pressed density of most scratchers makes this unlikely in practice. Wears out fastest of all common types.
Carpet-covered towers
The large floor-to-ceiling towers typically seen in pet shops. Platform boards: MDF or particleboard. Surface: synthetic carpet or polyester plush, stapled and glued. Structure: PVC-coated poles. At end of life, synthetic carpet fibres won't biodegrade, the MDF boards contain formaldehyde-based resins, and the plastic-coated poles are composite materials that can't be recycled. Nearly everything goes to landfill.
Premium natural-material products
The most sustainable end of the market. Solid hardwood or bamboo culm posts, natural sisal or jute surfaces. Better end-of-life options — solid wood can be chipped or composted, natural fibres will biodegrade. The problem is that even the best natural-material products on the market bond the surface to the structure, meaning the whole thing is still discarded when the surface wears out.
"The environmental problem with cat scratchers isn't the materials per se. It's the disposal model — built for single use, discarded whole."
The disposal problem — in numbers
Let's make this concrete. A mid-range sisal scratching post weighs roughly 1.5–2.5kg. A large carpet-covered tower can weigh 8–15kg. A household with one cat buying one replacement post per year is disposing of 1.5–2.5kg of mixed-material waste annually. A household with multiple cats buying larger products more frequently could be disposing of 20–30kg per year.
Across the UK's approximately 11 million cat households, even at the conservative end, the volume of cat furniture going to landfill each year runs into the tens of thousands of tonnes. It's not a catastrophic figure in the context of total municipal waste — but it's also entirely avoidable with a different product design.
The "natural" label — what it actually means
Walk into any pet shop and you'll find products labelled "natural sisal," "eco-friendly," or "sustainable materials." In the UK, none of these terms are regulated for pet products. They can mean almost anything.
"Natural sisal" typically means the rope wound around the post started life as a plant — which is true, and worth something, but says nothing about the adhesive used to bond it, the MDF core it's attached to, or what happens to all of it when the surface wears out. The sisal fibre itself is genuinely natural and would be compostable in isolation. In practice, it's inseparably bonded to a composite structure and goes to landfill as a unit.
This isn't dishonesty exactly — it's selective disclosure. The natural element is highlighted; the problem elements aren't mentioned. The net result is a purchase decision made on incomplete information.
Where the meaningful improvements are
Surface bonded to structure. Whole product discarded when surface wears out. MDF, adhesives, and synthetics go to landfill as a composite unit.
Structural post lasts indefinitely. Only the scratching surface is replaced. Natural fibres composted or returned. No structural waste per replacement cycle.
Resin binders prevent recycling. Synthetic fibres don't biodegrade. Plastic components are mixed-material and low-value for waste streams.
Bamboo: rapid growth, no resin binders, compostable at end of life. Jute: food-grade natural fibre, compostable. No synthetic components.
The two improvements compound each other. Better materials reduce the impact of each unit produced. A replaceable surface system reduces the number of units produced. Together, they represent a genuinely meaningful reduction in the category's environmental footprint — not through offsetting or greenwashing, but through straightforward design decisions.
What we're still figuring out
We try to be honest about where the story isn't clean. Bamboo is typically grown in East Asia, which means transport emissions are part of Culm's footprint. Jute requires water and agricultural land to produce. Packaging for sleeve refills has a footprint. None of this disappears because the end-of-life story is better.
Our long-term ambition includes a freepost returns programme for worn sleeves, compostable packaging, and full published data on the product's lifecycle impact. We're not there yet — Culm is a pre-launch business and these things require scale and capital to do properly. But the architecture of the product is designed to support those ambitions as the business grows.
If you want the full detail on materials, the materials journal article covers the bamboo versus wood versus sisal question in depth. And if you want to understand the refillable product model more broadly, the refill economy article puts Culm in the context of how other categories have solved this problem.
Most cat scratchers are worse for the environment than they need to be — not because the materials are catastrophic, but because they're assembled in a way that makes the whole product disposable when only the surface has worn out. The fix isn't complicated. It's a replaceable surface and better materials. That's what Culm is.