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CAT conversations: Janna Laan Lomas – Founding Director of Grain Architecture

CAT conversations: Janna Laan Lomas – Founding Director of Grain Architecture

Home » CAT conversations: Janna Laan Lomas – Founding Director of Grain Architecture

Janna Laan Lomas graduated from a CAT postgraduate course in architecture in 2014. She now runs Grain Architecture, a design practice specialising in the use of natural low-carbon materials. Alis Rees caught up with Janna when she visited CAT to share her knowledge and journey with current students on our MArch Sustainable Architecture course.

Janna Laan Lomas
Janna Laan Lomas

Alis: What were the best things about studying at CAT?

Janna: There were so many great things. If you’d asked me this in the first few years after finishing the course, I think I would have said the people. The community that you become part of is amazing, and the inspiration you get from other enthusiastic people is infectious.

But I’m also becoming more appreciative now of the content of the course and the integrated approach to a broad range of topics, not just on sustainable architecture but the whole built environment. I particularly value that we learnt to understand buildings more holistically, thinking about energy-efficient design and building performance, but also how buildings impact all the different systems that support them and their inhabitants, from health to ecology. That kind of holistic and integrated teaching was really valuable. It definitely influenced everything I do and the way that I think.

AR: How did your experience studying at CAT influence your journey after graduating?

JL: I’ve always been interested in the environment, but I think more from an ecological point of view, so although some of the building techniques and materials were completely new to me, other sustainability concepts weren’t. I’ve always loved nature and had a desire to be self-sufficient, since I was a child. But going to CAT opened my eyes to a lot more. My understanding of sustainability broadened massively, thinking about energy, carbon, pollution, resource depletion, water, soil, air, and material circularity.

After CAT, I desperately wanted to use what I’d learned and have maximum impact on the world, especially with the urgent need to act on the climate and biodiversity crisis. So I set up a business!

AR: What is Grain Architecture?

JL: Before I set up Grain, I’d been speaking to people, including other architects, and realised that not many architecture projects or practices were using natural materials. I had all this knowledge from CAT and thought I can surely apply this and offer it to clients. So I started working on small projects, which became larger projects, and that turned into me setting up my own practice. At the time I started Grain it was just me and occasionally freelance architects helping out. There have been some challenging times such as during covid, but we’ve generally been steadily growing and are now a team of four, including fellow CAT graduates Andy Hales and Jen Rawlings.

We’re a small ethical design practice, specialising in the use of natural low-carbon materials. We aim to create healthy, breathable, beautiful spaces supporting land and ecological regeneration, carbon sequestration, using safe materials, high-performance design, cradle-to-cradle analysis, retrofit, and Passivhaus techniques. We’re quite niche (sadly) and there are still very few other practices doing what we do, but I definitely see our dedication as our strength, and the specialism helps us focus on having a positive impact on both the environment and the people we work with.

AR: Why is it so important to you that we educate students, architects, builders and designers about using natural materials?

JL: It’s so important. Our natural ecosystems are in severe decline and the impact our building sector has on the environment is huge. We have so much work to do as an industry; using sustainable building techniques in newbuilds is essential, and there’s an awful lot of retrofit that needs to happen. But it’s key that this is done without using carbon-intensive materials and methods, otherwise the carbon footprints could outweigh the carbon savings of improved performance. It’s absurd that embodied carbon is still not regulated.

So we need everyone in the industry to understand a whole range of materials that are different to the conventional materials currently used. Upskilling builders to use natural low-carbon materials – timber, wood fibre board, hemp, straw, clay, lime and so on – and grasping the physics that goes with that, i.e. understanding moisture and condensation, would actually help tackle the health crisis too.

Ultimately I want other architects to know and do what Grain does. Sustainability should be embedded in training and education so that it becomes the norm.

What CAT is doing is great. With my employer hat on, I look at a student who has studied at CAT and instantly know they’re going to have good holistic knowledge of environmental issues and sustainable architecture broadly, which is such a positive thing. What I learned at CAT is what everyone should be taught. The teaching gives you not just the background information about materials, but also teaches you how all things link together, which is what makes it so incredibly valuable.

About the author

Alis is CAT’s Graduate School of the Environment Marketing and Communications Officer. You can get in touch with her at or click here to discover more about our postgraduate degree programmes 

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About our Masters in Architecture (Part 2)

CAT has taught Sustainable Architecture course (part 2) for ten years. Our course encourages students to combine design-based academic study with hands-on learning and to explore how doing architecture differently can help in creating a better and more sustainable future.



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