Is your home ‘ultra-processed’? Why architects are rethinking what we build with

How ultra-processed is the built world around us? The answer, for now at least, is very.

Highly manufactured building materials, many of them chemically engineered, reign supreme in modern construction. From our homes and offices to schools and hospitals, we are surrounded by polymers, sealants, adhesives and synthetic composites.

What is ultra-processed architecture?

The result? Often, a homogeneous, mass-produced design with an unhealthy side of toxicity. 'We are, quite literally, living in a plastic world,' says Gina Ciganik, chief executive of Habitable, an organisation focused on reducing the use of hazardous chemicals in building products. 'We need to start thinking a lot more about what we are surrounding ourselves with and breathing in. With 2.5 trillion sq ft of real estate projected to be built by 2060, the materials we choose going forward really matter.'

Thankfully, a shift is underway. Just as we are becoming more aware of the detrimental effects of ultra-processed food on our bodies and minds, so are we beginning to question our exposure to highly processed – and potentially toxic - materials in our buildings. 'We are starting to understand that making our buildings, spaces and places healthier is the most important thing we can do for our health and the health of our families and children,' says Carrie Denning Jackson, head of innovation and technology at US developer Jamestown and founder of Places as Medicine, an organisation dedicated to creating healthier places and spaces.

Buildings represent 'one of the greatest public health opportunities of this century,' says Harvard University’s Healthy Buildings Program director Joseph Allen. And that opportunity stretches beyond improving our physical health. Many architects believe that a shift towards using more natural, and often less uniform, materials will also lead to longer-lasting, more sustainable spaces where people feel more emotionally connected to the world around them.

For Robert Douge, co-founder of architectural practice Arya Douge, creating low-tox homes and buildings is about more than just reducing exposure to VOCs, the volatile organic compounds found in highly processed building materials. It’s about originality. 'At a time of digital saturation and AI-generated perfection, people want real, natural materials,' he says. 'The market has become saturated with cheap, accessible, ultra-processed fakes. A porcelain tile that has been mass-produced in a factory might look flawless, but it’s not real. A piece of marble straight out of the quarry with a unique imperfection is yours, and yours alone.'

'One of the best tapware suppliers we work with, Studio Ore, specialises in unpatinated finishes. The taps are left to age and patina, so everyone gets a very high-quality tap but, by virtue of how you use it and where it is, six months into owning that tap, it will be different to any other in the world.'

It was this pursuit of the unique that saw homeowners Emma Trachtenberg and Edward Pearse Wheatley turn to reclaimed materials and one-off finishes during the redevelopment of their Victorian terraced house in north-west London. Among their finds were an original butcher’s block, repurposed as a kitchen island, and hand-poured bathroom tiles.

Such a vehement quest for individuality is what Sam McNally, co-founder and director of architectural studio Echlin London, tries to instil in his clients. 'Take kitchen surfaces,' he says. 'People are often warned against marble because it stains. But think of it like a leather wallet. The first mark will bother you the most, but then the stains become part of your story. Do you want your island unit to look box-fresh in ten years? Or do you want those red wine and lemon juice stains to remind you of the life you have lived?'

Not that marble is the only option. At The Dairy, a residential scheme in Notting Hill that has seen the redevelopment of a 19th-century working dairy into eight homes, Echlin used leathered rather than polished Taj Mahal quartzite - a more practical, but still 100% natural, choice of stone.

It’s the replicas, says McNally, the heavy lacquers and high-gloss finishes, that bring chemicals and toxins into a building. That and mass-produced joinery, adds Olga Turner-Baker, managing director and co-founder of Ekkist, a design consultancy specialising in health and well-being in buildings. 'Composite joinery is wood pulp mixed with glue and sealants,' she says. 'Chewed up, wrapped wood products full of chemicals.'

At Pensaer, an architectural practice focused on the process of making, natural materials are used not only for their health benefits but because they age well. 'Rather than introducing unnecessary synthetic layers, we allow materials to weather and develop character over time,' says head of studio Paula Morgan. Internal clay render was used alongside the existing brickwork at Ashbourne Grove, a home in London’s East Dulwich, to naturally regulate humidity and at Casino Avenue in Southwark, the practice used raw materials at touch points, including a salvaged stone countertop.

None of this is easy, of course. 'Natural materials are regularly value engineered out of projects due to higher costs,' says Jamestown’s Denning Jackson. 'And we still don’t know the durability of some of these materials. We used cork in one project that started bubbling, so we had to fix that and then educate the installers on how best to work with the material to avoid it happening again. This is all challenging stuff, but experimentation is at the heart of change and innovation.'

And the use of natural materials is successfully shifting perceptions around what constitutes a healthy building, even in highly regulated spaces. At the New Velindre Cancer Centre in Wales, natural, anti-fungal materials help to improve the health of the building’s end-users. 'The heart of the building is mass timber, and in the patient areas we have made the walls out of hemp and lime render, which are all naturally anti-bacterial,' says Christian Dimbleby, head of sustainability at White Arkitekter. 'They are also breathable, so toxins naturally escape. We came up against standards written for modern materials and had to prove that traditional, natural materials are suitable in healthcare settings. We are pushing boundaries to show that if you use unprocessed materials, you are reducing the risk of unknown chemicals and toxins. We want the general public to know that.'

We have the technology, the machinery and the processes to create flawless replicas at pace. But the tide looks set to finally be turning.