Passivhaus at Morrow + Lorraine


Unperturbed by the pandemic, in June last year our Head of Sustainability, Stephanie Crombie, completed one of the first online Passivhaus courses run by WARM consultancy. Here she reflects on the principles she learnt, and the opportunities Passivhaus brings to add significant long-term value to buildings, while contributing to net-zero targets.


2020 was the year that sustainability rose to the top of our agenda. Becoming a Passivhaus certified designer allowed us to see the benefits of how scientific principles and evidence-based metrics could improve our architecture. Passivhaus is the first of a number of new environmental skills we are adding to our repertoire that will allow us to build a more sustainable future.

Broadly speaking, if we want to become a net-zero nation our buildings will all have to use less energy; around 40% of the UK emissions come from construction. What Passivhaus offers is a performance-based certification, anchored in rigorous dynamic modelling that promotes a fabric first approach to design. Passivhaus adds a level of scrutiny right through to construction, with targets required for both airtightness and operational energy to reduce a building’s carbon emissions and create long-term value.


Our Passivhaus certified designer and Head of Sustainability, Stephanie Crombie

We are yet to complete a Passivhaus project at Morrow + Lorraine, but we are keen to push for this route towards a net-zero built-environment. There are many other elements to consider, such as building typology, retrofit, and conservation, however we are finding that applying Passivhaus principles to our projects has already made a significant difference to our design ethos.

Today, more of our clients are asking, ‘what can we do to make our buildings more sustainable?’. There are many motivations to this question, particularly in the light of the pandemic; from changing occupation patterns and greater consideration of health and wellbeing, to long-term goals about cost, durability and value. Passivhaus is part of the answer. By prioritising performance, reducing our operational carbon emissions, and creating comfortable and healthy environments, Passivhaus offers one of the most significant solutions to sustainability.

“Applying Passivhaus principles to our projects has already made a significant difference to our design ethos.”

The knock-on effects of undertaking the Passivhaus course is that it has paved the way for other sustainable design concepts at Morrow + Lorraine. We are exploring low embodied carbon and mass timber construction, how we can better integrate landscaping into our architecture, and how we can reduce our ecological footprint by harnessing materials from the circular economy.

What’s most positive is that we are finding the more we talk about these topics, the more action we are seeing. Passivhaus has been our awakening and we are really excited about the scope it offers to create a more sustainable, resilient, and ultimately regenerative practice for the future.


Contact Stephanie at or carry on the conversation with us here.