Latest / The Manufacturing Podcast with Fexingo: Factories, Supply Chains, and Industrial Business / How a UK Factory Is Making Bricks from Construction Waste
Transcript
- Lucas: Last month I drove past a building site in central London where they were demolishing a 1970s office block. Steel skeleton, concrete floors, brick cladding. And I thought — every single one of those bricks is going to a landfill or, best case, being crushed into low-grade aggregate for a road base. That's the standard ending for most demolition material. Luna: Right, downcycling. You're not making a new brick out of that old brick. Lucas: Exactly. But there's a factory in the UK that's proving you can. It's a brick manufacturer called Kenoteq — based near Edinburgh — and they've developed a process where 95 percent of the raw material comes from construction and demolition waste. We're talking crushed bricks, concrete, plasterboard, even old glass. They press it all into a new brick that's almost indistinguishable from a traditional clay brick, but with a fraction of the carbon footprint. Luna: How does the process actually work? Because clay bricks are fired at over a thousand degrees. That's where most of the emissions come from. Lucas: That's the key difference. Kenoteq's brick doesn't get fired. It uses a binder — they're tight-lipped on the exact composition, but it's a combination of industrial byproducts and a small amount of cement-like material — and then the brick is cured at low temperature using waste heat from a nearby data centre. So you skip the kiln entirely. The curing temperature is around 60 to 80 degrees Celsius, compared to over 1000 degrees for a clay brick. That cuts the carbon emissions per brick by about 80 percent. Luna: And the raw material is basically free? They're getting paid to take waste off demolition contractors' hands? Lucas: More or less. They charge a gate fee for accepting the waste — standard practice at recycling facilities — so their raw material cost is actually negative. They're getting revenue on both ends: inbound from waste disposal, and outbound from selling the finished bricks. That's the economic moat. They told me their profit margin is healthy even without any carbon credits or green premiums. Luna: So it's not a subsidy play. That's rare in circular economy stories. Lucas: Very rare. The founder, a professor of civil engineering at Heriot-Watt University, started the company in 2017. It took them six years to get the product certified for structural use in the UK — building regulations are understandably conservative about new materials. They got full certification in 2023, and now they're producing about 30 million bricks a year. That's still a drop in the bucket compared to the UK's total brick demand, which is roughly two billion a year, but the trajectory is interesting. Luna: Thirty million out of two billion is 1.5 percent. But if they can scale to even 10 percent of the market, that's 200 million bricks a year — and a huge amount of waste diverted. Lucas: Right. And they're not the only ones trying. There's a company in the Netherlands called StoneCycling that makes 'WasteBasedBricks' — similar concept, but their recipe includes things like discarded ceramic tiles and even old glass. They're targeting the architectural market, selling to high-end projects that want a story. Kenoteq is more utilitarian: they're going for volume, selling to large housebuilders like Barratt and Persimmon. They want to be the default brick for new housing estates. Luna: And the housebuilders care about cost, not just carbon. So if Kenoteq's brick is cheaper or comparable to a clay brick, that's the real engine of adoption. Lucas: Exactly. They claim their brick is price-competitive with standard clay facing bricks — within a few percent. And now there's a new regulatory tailwind. The UK government passed an embodied carbon tax on construction materials late last year — it takes effect in 2027 — so every tonne of CO2 embedded in a building's materials will carry a cost. For a typical brick-clad house, that tax could add something like 500 to 1000 pounds to the material cost. Using Kenoteq's bricks would slash that tax bill by 80 percent. That's a direct financial incentive for builders. Luna: So the tax essentially creates a price gap that makes the low-carbon brick cheaper overall, even if the sticker price is slightly higher. Lucas: That's the thesis. And if the tax is high enough — it's currently set at around 50 pounds per tonne of CO2 — it flips the economics decisively. Kenoteq is already at capacity and they're raising capital now to build a second factory. They're targeting six factories by 2030, which would bring total capacity to around 200 million bricks a year. Luna: That's a big jump. But the waste supply is there — the UK generates about 60 million tonnes of construction and demolition waste every year. So the raw material is abundant. The challenge is logistics: waste is heavy and expensive to transport. Each factory needs to be close to both demolition sites and building sites. Lucas: Exactly. Kenoteq's first factory is near Edinburgh, but they're looking at sites in the Midlands and the South East for the next ones — closer to London, where demolition is constant and housing demand is highest. The model is local loops: each factory serves a radius of maybe 50 miles for waste intake and 100 miles for brick delivery. That keeps transport costs down. Luna: And the data centre waste heat — that's a clever piece of pairing. Is that replicable? Not every location has a data centre nearby. Lucas: It's a nice to have, not a requirement. They can also use natural gas boilers for curing and still be far cleaner than a clay kiln. But the data centre partnership is a neat example of industrial symbiosis: the data centre needs to dump heat, and the factory needs low-grade heat. Both win. They've got a memorandum of understanding with a large data centre operator in the UK, so future factories may be co-located. Luna: So you've got cheap feedstock, low energy input, a product that's certified and price-competitive, and a regulatory push coming. What's the catch? Why hasn't this scaled faster globally? Lucas: The biggest barrier is certification. Every country has its own building standards, and getting a new brick approved for structural use takes years and costs millions. Kenoteq spent six years and roughly three million pounds on testing and certification in the UK alone. Expanding to Europe or the US would mean repeating that process in each jurisdiction. That's a huge capital outlay for a relatively small company. Luna: So regulatory fragmentation is the real bottleneck, not the technology or the economics. Lucas: That's the story across most circular construction materials. The technology works; the unit economics work. But the path to market is long and expensive because building codes were written for virgin materials. There's no fast track for recycled-content products, even if they perform identically. Some countries are starting to change that — the EU's revised Construction Products Regulation includes provisions for 'circularity assessment' — but it's slow. Luna: It's a classic first-mover disadvantage. Kenoteq spent the time and money, and now they have a lead. But the clock is ticking on the carbon tax implementation — 2027 in the UK. Other companies are watching. Lucas: And there's another angle: the aesthetics question. Architects and developers often choose bricks for their colour and texture. A recycled brick looks slightly different — it's more uniform, less variegated. Some people love that; some say it lacks character. Kenoteq has addressed this by offering a range of pigments, but it's still not a perfect match for traditional handmade bricks. For housing estates that's fine, but for heritage projects it's a non-starter. Luna: So they're going after the volume market, not the boutique market. That's probably the right strategy for carbon impact. Lucas: Yeah. If you're building 500 houses on a greenfield site, you don't need a bespoke brick. You need something consistent, strong, and affordable. Kenoteq's brick meets all three. And with the carbon tax coming, it'll also be the cheapest option on a total-cost basis. That's the inflection point they're betting on. Luna: It reminds me of the early days of recycled steel. For decades, steel mills used virgin ore because it was the established process. Then electric arc furnaces got efficient, scrap became abundant, and now recycled steel is the default in many markets. Bricks might follow the same curve. Lucas: That's exactly the analogy. Recycled steel took about 30 years to go from niche to mainstream. If bricks follow a similar path, we're in year seven or eight. The next decade will tell us whether the regulatory push and the cost advantage are enough to overcome the inertia of a centuries-old industry. Luna: And if it does work, it's not just bricks. The same logic applies to concrete blocks, roof tiles, pavement slabs. The entire built environment could shift toward a circular model. Lucas: Exactly. Kenoteq is one factory doing one product, but the blueprint is there. And that's what I find most hopeful about this story: it's not a moonshot technology. It's clever recycling of existing processes, with a business model that works today, not in some hypothetical future. It's worth a closer look.