Projects: Frongoch


Keywords: retrophit

A renovation and extension project of a courtyard of derelict stone buildings; outside Aberdovey, Gwynedd. The building work was completed in 2006, and the project subsequently won an award for its quality as a tourism facility in the Snowdonia National Park.

The focus of the renovation was not towards a specific energy standard; but to focus on good quality energy efficiency ( Internal Wall Insulation was required, due to need to maintain the stone exterior) ; improving comfort, air quality, and avoiding damp / condensation problems.

All our portfolio projects


A garden outbuilding in Hereford, designed by Andy Simmonds, built by Fraser Williams with apprentice, Raimi Wye. Complete Summer 2022. Brief description from Fraser ‘ We built this garden room in the summer of 2022. I was the main carpenter working alongside apprentice Raimi Wye. Andy Simmonds provided a lot of practical support during the build – such as input on building details and construction techniques – and drew up all...


Retrofit of 1960’s bungalow in the Malvern area. Completed towards the end of Summer 2022. Design to AECB Retrofit Standard – see Project management and specialist contractor – Main Contractor Oneport Building Ltd. This was the second retrofit scheme that we’ve worked on a ‘better building model’ – lockdown meant progress on some of these jobs was very slow – good builders even harder to come by than...


The Chestnuts featured in a ‘Passive House Accelerator’ webinar in May ’22 See links to Youtube recordings here : Partel: Accelerator: It also features on pg. 98 of their Summer magazine. See this link This is a near-Enerphit standard retrofit of a 1950’s detached house in Chepstow. After months of waiting through the lockdowns of 2020, a contractor from Newport was selected to work alongside The...


Our clients here had a small cottage with extremely narrow stairs to a limited head height loft area. It quickly became clear that a replacement dwelling was the best option. We designed a timber frame flat roof house; this has achieved Passivhaus target for energy efficiency. The completed project is not yet certified, but that is the clients’ intention. The house was built by local passivhaus / timber frame specialists,...

Tanzanian Eco-Village

The images here are from our stay at the Eco-Village in November 2018; Alan Clarke, Adele Mills and Andy Simmonds joined our clients for a memorable few days on site. Key purpose for the visit was to study the test building built that year; install monitoring equipment in this building and existing orphanage houses; carry out site survey and investigate ground water level; determine specific site for future projects. Next...

Hereford retrofit


A new replacement dwelling in Oswestry was complete in January 2020. A draughty 1970’s bungalow with subsidence issues on the site would have been expensive and difficult to improve to near Passivhaus standards of energy efficiency. After debate on pros and cons, it was decided to demolish the bungalow and build a near-Passivhaus two storey dwelling. This choice gave the chance to place the house to allow increased solar access...

Garway Community Centre

The rural Herefordshire village of Garway finally has its new Passivhaus certified community centre. It has taken many years’ development, but a successful bid to Big Lottery Fund in 2016 made the project a reality.The building was completed with a grand opening in April 2018.  The centre provides many functions for the village, including a large multi-functional hall with full stage / green room etc; an outreach medical centre; a cafe/bar, part-time...

Harold Street

A high-quality deep retrofit. Work carried out by Tom Straker, AECB member. Completed 2015. The clients are committed environmentalists, and were keen to demonstrate best practice in this modest town house.

Church Cottage

Part retrofit, part new-build extension to a small-holding cottage on the Welsh borders. Building work carried out by Mike Whitfield builders, AECB members.