Applying Passivhaus principles make sense: Josef Horner, LHC’s Passivhaus Designer

Buildings are a significant culprit in carbon emissions, and some of the responsibility for addressing this falls to architects, engineers and our clients.

Upskilling in this area is critical and some time ago LHC decided to invest in Passivhaus training for its architectural team, not only to enable us to design to this benchmark, but also to inform architectural design across the practice.

The Passivhaus ‘fabric first’ approach should underpin the basis of any building project which strives to perform well.   Jo Horner, LHC’s Passivhaus Designer

Passivhaus explained

The ultra-low-energy Passivhaus approach sets a gold standard for building performance that’s recognised globally. Design elements include high levels of insulation, an airtight building fabric, thermal bridge-free construction, high performance windows, and mechanical ventilation and heat recovery.

Passivhaus is the fastest growing energy performance standard in the world. It slashes energy use from buildings and delivers high standards of comfort and health. The design principles are increasingly being adopted by architects, including LHC, to deliver low energy buildings.

How does having a Passivhaus Designer on our team benefit our clients?

The principles of Passivhaus design are relevant to a variety of building typologies. They’re applicable to both new-build and retrofit, across residential, education and commercial sectors. The design elements that contribute to a Passivhaus building must be considered holistically and interrogated early. They ultimately result in a thermally robust building which – whether certified or not – will maintain high levels of comfort for occupants and a reduction in operational energy and costs. In fact many UK buildings adopt the principles but never seek certification.

Architectural Associate Josef Horner, based in LHC’s Plymouth studio, completed the rigorous training and qualified as a Certified Passivhaus Designer last year.

Investing in my training underlines LHC’s commitment to addressing wider issues relating to building carbon footprints. It’s a clear demonstration of the company’s commitment to energy efficiency and to taking action on climate change.

A qualified Passivhaus Designer has a solid understanding of the fundamentals of M+E systems, airtightness and thermal performance and the principles necessary to reduce space-heating demands. This understanding allows for meaningful interaction between the architect and the wider design team, and effective co-ordination and design decisions on site.

Stronger sustainability regulation must surely be on the horizon with the climate crisis becoming ever more urgent, fuel poverty growing and regular new commitments to Net Zero. In 2021 LHC became a signatory to UK Architects & Landscape Architects Declare movements and to the RIBA’s 2030 Climate Challenge and established its own Environmental & Sustainability Working Action Group. This draws expertise from across the practice to develop LHC’s Sustainability Road Map. The Road Map is a live document; we’re constantly exploring ways of delivering sustainable design approaches within our projects and regularly reviewing ways to reduce our carbon and environmental footprint.

We offer a wide range of sustainable design services to our clients and Passivhaus Design is an important ingredient in this mix.



Low energy home in the Green Belt
Jo is currently Project Architect on a new build house which incorporates low energy principles such as super-insulated envelope, airtight contruction, high performance glazing, heat recovery ventilation and a highly insulated timber frame.