Conversations: Amin Taha

Constructs What are your plans for the Fall semester? What is the studio project, and what are your goals for the students?

Amin Taha Ethical foundations and frameworks to ethical outcomes. For a number of reasons, not many schools of architecture teach material technology anymore—in terms of structural capacity, fire properties, and embodied carbon, the latter being the most urgent at the moment and that which we will focus on. In both practice and teaching, it raises the following questions: If that’s missing at the beginning of your design process, then what are you drawing? What’s the purpose? What is your drawing but beautiful forms, shapes, and atmospheres? If the design’s embodied carbon is dramatically more than it could be with the simple choice of an alternative material, then its ethical measurement is no longer beautiful.

So the core of the program will be a brief teaching module that describes all materials. Most students will hopefully know their strengths to some degree, as well as their visual and poetic allusions; beyond that, it is demonstrating the embodied carbon, and how you could easily swap one material element—a steel frame, reinforced concrete, or fired-clay brick— with another that has dramatically lower or even carbon-negative outcomes.

C That’s a fascinating project. Yale’s Center for Ecosystems in Architecture, founded by Anna Dyson, has been exploring all sorts of materials that help reduce the carbon footprint of buildings. One of the faculty members, Mae-Ling Lokko, was featured this year in the British Pavilion at the Venice Biennale, and her research focuses on biomaterials made from agricultural waste. That could be an interesting crossovers.

AT Hopefully we can make use of this expertise. I’m thinking low-tech: I get a piece of timber and glue or screw a piece of stone to it, for instance, a project with Webb Yates Engineers to replace concrete floors. The central government funds London’s Design Museum to research ways to decarbonize the broad spectrum of design, part of which is obviously the building sector, architecture. We have about half a million pounds, half of which is for building a prototype that’s three or four stories tall as a structural frame to replace reinforced-concrete or steel frames. The other half goes to Professor Wendel Sebastian’s University College London lab to physically test and examine how they meet existing European, British, and U.S. building and engineering codes.

It might be useful for the students to have a go at taking a glulam beam, or even just a normal timber beam, and screwing or gluing stone slabs to it to demonstrate substitution for heavier embodied carbon concrete and steel structures and lowering operational carbon by using the stone for seasonal thermal mass. And then, similarly, what do you do with the column? Take pieces of stone, drill holes in them, insert a metal rod, put two nuts on either end and show how that works as a pretensioned column. Hopefully we can assemble and test this in Yale’s workshops.

C We have fabrication shops inthe basement, including a metal shop with a hydraulic press, in case you want to crush things.

AT That’s exactly what we wantto do. At the Royal College of Art (RCA) we call it a live project, where you make one-to-one models and test themto destruction.

C Is this a line of research you’ve undertaken in previous teaching experiences?

AT At the RCA we started off exactly like that: Let’s find out what the embodied carbon of these materials is. In 2019 we collated and reorganized the 2017 Building Services Research and Information Association (BSRIA) report. The University of Bath Inventory of Carbon and Energy collects the EPDs(Environmental Product Declaration)of all materials. They’re very honest about them; you can see a graph of scattered EPD reporting. We’d take the mean and convert CO2 per kilogram of material into CO2 per cubic meter, as most BIM models already generate volume data.

With engineers from Buro Happoldand Webb Yates we created a spreadsheet based on EN15978, the internationally adopted embodied carbon measure for buildings across their lifespan, where you plug in the material types and their volume from an existing design and then alternative materials that perform the same structure. That was the first year. We ran it for about three years to keep building that knowledge and then expanded it into operational carbon; it was like a PhD project being undertaken by fourteen students. After four years we set most of it aside to allow space for broader design ethics. The RCA is publishing the research in book form in late 2025.

C Did this train of investigation start before or after your experiment in structural limestone?

AT After. From the lens of truth to materials, letting materials and their assembly speak, we wondered that if you really want to follow what Edward R. Ford calls the “articulated joint,” which with the “autonomous detail” he defines as the only two types of detail that are legitimate— everything else is evil—where does that lead? We found it’s the same argument that Semper and Bötticher would have made a hundred and fifty years ago: the tectonic assembly of Kernform. Its joining and binding drives and completes the emblematic Kunstform.

Another way of getting that message across is to define it as “lazy architecture.” Draw or specify a single piece of limestone to act as column or beam, instead of a steel or concrete column with fire and waterproofing applications, insulation, and vapor barrier needing to be penetrated with galvanized cladding and support clamps before being resealed, then more clamps bonded to glass fiber–reinforced stone veneer tiles. All of that detailed and coordinated and changed multiple times with every repositioning of a window and door location. That’s a lot of materials to coordinate, assemble on site, pay for, and warranty. Lots of time and cost and opportunity for failure. Hence the single material defined as lazy, if not ethically greener, faster, and cheaper for our clients, if not “materially true.” Within our practice? The satisfaction, the architecture, is almost driven by the skill of the quarry master extracting the stone with and against sedimentary layers, the stonemason who prepares it, and the structural engineer who sizes everything and helps with the joints. As architects, we’re guiding that process as opposed to beautifully drawing it and demanding that it follow an abstraction based on little knowledge of the beautifully simple process of extraction, preparation, and assembly, a beauty that is defined by that ethical outcome as well as the visual and poetic allusions of the material.

It was only after our sustainability engineer undertook his final assessments once Clerkenwell was completed that we realized there was a 98 percent drop in embodied carbon compared to a steel-frame cladding. That’s absurd! Had we understood that earlier, we would have done a number of other things differently throughout the building, not just the exoskeleton. As we had too few and not particularly varied scales of projects in the office, we thought, Let’s get fourteen brains at the RCA school of architecture and another twenty or so at UCL’s engineering faculty to accelerate and spread that learning.

C Another angle on saving carbonis reusing old buildings. We often talk about historic preservation or adaptive reuse. Your work has a strong point of view toward history, but it doesn’t quite fit within the remit of these two concepts because you’re making new buildings in the form of old buildings. How would you frame your attitude toward history and interest in using new materials to create old forms, or old materials to make new forms?

AT Up until the 1970s in this country, conservation preservation hadn’t become mainstream. Most architects and planners were still happy to demolish whole swathes of Georgian and Victorian London, despite the fact that no bombing had occurred in those areas. It was that postwar period: two generations had brought upon us two world wars, so let’s reject their outlook and take on Modernism as emblematic of a new future.

Then there was a sort of crisis that coincided roughly with the first oil shock. People began to ask, Why are we demolishing beautiful parts of London for these Modernist visions? The language of planning began to change beginning with a social vision of respecting functioning neighborhoods. This language struggled to be articulated as planning guidelines, settling on visual conformity, mimicry to be policed by conservation officers, legislated at a local level initially before becoming national planning policy. This wasn’t going to be applied everywhere, but in certain redlined areas deemed, often by a single conservation officer, to be of historical interest needing respect and conformity. The language has recently changed. Yet the meaning is still there; it’s still read and interpreted the same way by conservation officers.

Since the 1970s these areas have suffered a sort of self-fulfilling prophecy, with whole streets mimicking stretcher bond with the cheapest brick they could get that year—all in cement mortar, not lime, with window patterns that barely have any relation to the neighbors, and all suspended from a concrete or steel frame. This is evidently not conservation but a poor representation of the past that does the authentic material and social structures no service. What else does it do? If instead of building with load-bearing brick and stone, you’re suspending these pseudo historic materials from the same frame that in another area might be hanging lighter weight glass, then around 30 percent extra material, cost, and carbon is used.

What kind of intellectual conversation are you having with your historic neighbor? One that’s wholly superficial, with little respect, arguably insulting by mimicking their external clothing but in cheaper materials to say you are the same. It is easy enough to suggest to conservation officers that if you’re going to work in these areas, you need to dig a bit deeper and go beyond the skin of your neighboring building.

For example, in an area where whole districts are pattern-book housing— three rooms downstairs and three rooms upstairs—by eighteenth- and nineteenth-century builder-architects, you might have the following argument with the conservation officer: How can we do that today? If we had to build streets and streets of it, how do we make structures that provide a pleasing aesthetic outcome at a cost that accommodates affordable housing? The outcome might be that if you squint your eyes, bricks of the same module as the historic structures are used. But today’s necessarily different structural system is viably repeatable. Philosophically, it follows the same idea as pattern-book mass housing from the past, without having to look exactly the same.

C Is that how you approach your projects?

AT Barrett’s Grove and Clerkenwell Close don’t look anything like theirneighbors, but they draw from and have a better understanding of that context than buildings of the 1980s nearby. If you had a conversation with an architect or builder from two hundred years ago—or a thousand years ago, as in Clerkenwell with the Normans—they’d understand what you’re doing: using brick and stone for structural purposes, using the least amount of material necessary, before molding these for “delight.”

The other end of working with existing buildings—retrofit and historic buildings—is something like Bleeding Heart Yard and Upper Street. One is a retrofit, an extension to an existing 1970s building; the other is just a new building. But they have similar arguments because they’re both in very well-regarded, sensitive conservation areas.

A WWII bomb site that had laid empty till now, Upper Street had to be new. We got early feedback from conservation officers and councilors, who have their town hall directly opposite, almost demanding we reinstate the original pre-war building. We said, Well, obviously we can’t because we can’t meet modern building regulations. However, we can recreate it in another way. When we initially explained it to the councilors, some were very receptive. When we described it at the planning presentation, where they would give us approval, they all stood up and gave a standing ovation, though I’m still not convinced the conservation officer understood what the result would be.

We said, Look, we’re going to make abuilding that’s a sort of polemic on society’s preference for nostalgia. Everybody was pretty much telling us, Let’s try to rebuild this past era. Architecture was better; the times were better. Even if flawed, it’s a universal feeling that the past somehow had fewer of the issues we deal with today, and a building is emblematic of that. Like monuments that we put on pedestals, we edit it, strip it of its nuances, and turn it into an ideal. So why not rebuild it as a monument, as a hollow monolithic casting? It’s a structural double skin tied with insulation in between, an external and internal cast that becomes this fictional fond memory that we’re all seeking.

The material choice had to immediately tell that story: reassuringly firm, but flawed. Terracotta cement mix was poured into formwork on-site, not quite settling in all areas. The formwork is taken from a point cloud survey of the symmetrical building on the other end of this terrace, reversed, and remodeled yet is inevitably imprecise. Then there’s human error in translating that survey into a CAD model and then the routing tools unable to fully follow the model. The formwork arrives upside down or is installed in the wrong location. The contractor didn’t believe our explanations and remained determined to correct it to the end. Then the interior—our contemporary modern habitant—is housed in warm, sequestrating timber rudely punching through and out of this memory to ensure light falls where it is needed.

C What about a project like Bleeding Heart Yard?

AT The client for Bleeding HeartYard was a commercial developer, andhe really hired us to raise the value of the building. We looked at the planning history and saw that a series of previous application designs had been refused on the grounds that the already ugly building was being made uglier. This was the skin-deep argument once more.

We noticed that you could probably go up two floors, but you could also go out the back where older buildings had been cleared for an executive car park. Donald Insall Associates, a conservation-oriented firm, had access to all sorts of archival files that most architects can’t get their hands on, and we found surveys of the eight buildings that were demolished in the late 1960s.Using these to map a three-dimensional ghost across the site, we drew an additional two stories up and out over the car park in a mass timber superstructure, doubling the net lettable area for our happy client. Better still, in improving the thermal performance of the building we placed a layer of super insulation on the outside. This left us with millimeters for the facade finish.

If the ghost of those eight buildings helped us find the original boundary lines and roofline so critical to the conservation area, why not reanimate them in one and a half millimeters of perforated, fabricated skin, with its two-hundred-year-old details? From a distance, in your peripheral vision, you perceive it as part of the established context. As you get closer, you see that it’s not brownstone firmly rooted in its setting but that there are bolt positions everywhere, belying a skin-deep curtain suspended off the ground. You get closer still, and you see daylight coming through the perforations. Reassuring permanence melts into air

C We’ve been talking about exteriors quite a bit, but your interiors are very poetic. You’ve also lived in your buildings. Do you approach interior architecture differently from exteriors?

AT In short, yes. The virtue of choosing irreducible materials as structure is that the same structure can be exterior or interior finish, sometimes both. If that is the start, any following layering is there for the interior narrative.

Barrett’s Grove, for instance, is fairly inexpensive housing, and it made sense to have a wall-floor-roof structure in cross laminated timber (CLT) with insulation on the outside and a self-supporting wall acting as a rain screen beyond that. Then internally, because it’s CLT, you’re not having to layer it with battens, plasterboard, skim coats, skirtings, and cornices—all those materials, all that labor, and the time on site are gone. Clerkenwell, for instance, uses its superstructure as external finish.

Once you’ve made that structure material decision, most of the work is done. Going back to Ford, Semper, and Bötticher, from a distance you have the general tectonics of the architecture, which might be enough on occasion. As you get closer, the “autonomous detail” can literally and figuratively layer that narrative, not necessarily dependent on the tectonics of the building, but revealing a certain poetry. For us, these become narrative details, especially at eye level, and tactile moments, certainly within, that expand the overall theme, so that the ethical drivers in the architectural program—affordability and low embodied carbon—become invisible.