Behind the doors of Passivhaus

As part of London Climate Action Week last month, the UK featured 14 Passivhaus projects in the International Passivhaus Open Days 2024, attracting over 200 visitors eager to experience the comfort of Passivhaus buildings. The tours saw a diverse mix of self-builders, building professionals and students exploring Passivhaus from Hexham to Devon.

Parklands, aiming for EnerPHit Plus. I Image © Eco Design Consultants

The June Passivhaus Open Days offered an opportunity to experience summer comfort and engage directly with the people behind these energy-efficient designs. A range of projects were featured, including certified self-build homes, a new build Passivhaus neighbourhood under construction in Somerset, a phased retrofit in Milton Keynes and a commercial building in Welshpool.

Mumbles Passive House visitor quote

These events allow visitors to experience first-hand the superior comfort and quality of the Passivhaus Standard, helping to dispel common myths. The summer edition also highlights the rigorous Passivhaus requirements designed to prevent summer overheating, demonstrating the year-round comfort of these buildings.

Parklands EnerPHit Plus visitor quote

Modern efficiency meets historic charm

Image credit: Warksburn Old Church

Warksburn Old Church aiming for EnerPHit project. I Image © credit: Warksburn Old Church

Anne and Alan James were delighted with the very strong interest in their Warksburn Old Church project. Over 70 guests booked to see the work in progress, as this complex and painstaking retrofit of an 1875 former church approaches completion. Anne and Alan were particularly pleased that so many visitors were specifically interested in the detail of how 21st Century levels of energy efficiency can be achieved in a retrofit. The project is successfully combining the Passivhaus fabric-first approach with deep integration of renewables and smart energy technologies, whilst also retaining and showcasing the heritage features of an historic building. Anne and Alan will be presenting the project at the UK Passivhaus Conference 2024 and are looking forward to sharing more detail on the techniques they employed, and how the project developed from initial brief to delivered solution.

Suzanne Carr, MGA’s Passivehaus Certified Designer had a great visit to this ‘in progress’ Passivhaus project at Warksburn Old Church as part of the Passivhaus Open Days organised by the @PassivhausTrust. Thanks for Anne and Alan for sharing their project. pic.twitter.com/DkAVb7xiXT
— Mosedale Gillatt Architects (@MosedaleGillatt) July 2, 2024

Passivhaus Q&As

As well as being able to experience the comfort of a completed Passivhaus, several projects under construction offered visitors a unique chance to understand the technical and quality assurance aspects of Passivhaus on site. Visitors were able to ask questions on all aspects of a Passivhaus project, exposed building structures allowed hosts to highlight air tightness and thermal bridging details.

Below are some of the common questions of the event;

1. Are MVHR (mechanical ventilation with heat recovery) and ASHP (air source heat pumps) noisy & how much do they cost to run?

Discover more about looking after your MVHR and when is the right time for heat pumps. Keep an eye out for our upcoming heat pump design guide and heat pump webinars for new builds and retrofits!

2. What are the running costs of a Passivhaus?

This is dependant on several factors such as your building typology, choice of fuel, & occupant use, learn more in our Passivhaus Costs guidance.

3. How difficult is it to deliver Passivhaus & how did you find a builder?

Including Passivhaus at the beginning of your design process assists smooth delivery & acheiving the standard much easier! Discover top tips in the How to build a Passivhaus: Good practice guide. A good place to start when finding the right team for your project is the PHT members directory. Also note who was involved with projects that inspire you - browse the UK Passivhaus Awards or project gallery for more designs.

4. What materials did you use?

Passivhaus is material agnostic. You can build to the Standard with any construction system. Other factors such as embodied carbon choices, availability of skills & materials, and planning restrictions will influence your decisions.

5. What type of heating system did you choose & why?

A Passivhaus provides a high level of occupant comfort using very little energy for heating and cooling. This makes on-site renewable energy generation effective at covering more of your energy demands and therefore you are less reliant on peak loads and have more energy security. Read more about Passivhaus Primers.

6. What are the cost differentials between Passivhaus & a standard new home?

The extra costs of building to the Passivhaus standard in the UK have decreased over time, with best practice costs in 2018 being around 8% higher than standard new homes. Considering the significant long-term savings on energy, reduced carbon emissions, and improved comfort and health, the initial cost differential becomes a minor uplift for a far superior product. Learn more in our Passivhaus Costs & Benefits guides.

Thanks to all participants

The Passivhaus Trust extends our thanks to everyone who generously welcomed visitors into their homes and buildings during the Passivhaus Open Days. We appreciate the projects that participated this year, as well as the owners and building professionals who make these tours possible.

Get involved next time!

These site visits are a fantastic way to share the benefits of Passivhaus living, with a high level of interest from the public. We are very grateful to everyone who took part this year and look forward to the Winter Passivhaus Open Days, running from 8-10 November 2024, can you open your Passivhaus doors? See you there!