Site visits to the E=0 pilot in Maldon, Essex, are allowing potential stakeholders to get a touch and feel experience of an Energiesprong retrofit whilst works are still in progress. On 7 March some 40 international Energiesprong participants visited the pilot where five Moat Homes Limited (“Moat”) properties are being retrofitted to the Energiesprong standard by ENGIE. Over 20 UK stakeholders also joined a site visit on 23 May to find out more.
From draughty, hard to heat houses to comfortable, warm homes
To meet the required standard, an Energiesprong retrofit must deliver 21°C year-round temperature in the living room, 40 minutes of hot water a day, plus adequate clean electricity to run appliances. In Maldon, a super-insulated shell is being wrapped around the existing structures which will dramatically reduce heat loss and will also reduce noise from the road.
In March the roof insulation panels were being dropped into place by a crane. However, windy weather on the day of the visit meant that this particular job would need to wait for calmer conditions.
Windy weather is common in Maldon and one of the particular challenges faced by the Maldon pilot customers. Their homes are highly exposed with wide open land front and back and the coastline within walking distance. This exposed rural location is one reason that households had found themselves paying high energy bills, despite the homes having cavity wall insulation.
As a measure to block the through-draughts, glued polybead insulation has been blown into the 300mm void below the floors of the pilot property. This means it is now closer to a solid insulated floor. Insulated wall panels have also been installed and insulation extends below the damp proof course in order to block the wind and heat loss originally picked up by a thermal imaging camera.
When the retrofit is done, Moat customers will find themselves in a comfortably warm, net zero energy home.
Offsite panel manufacture to speed up installation
Matt Ratcliff from insulation specialist Mauer was on site on 7 March to explain that 200mm insulated wall panels of one-storey height and half elevation width had been manufactured offsite to ensure their integrity and would be craned into place.
Mass customisation and industrialisation is needed to bring down the cost of retrofit if retrofit is to scale to respond to the challenge to reduce carbon emissions. In particular, offsite manufacture and assembly of insulated wall and roof panels will be a must to ensure faster retrofits with minimal disruption to occupants. By brokering large volume deals with social housing providers, Energiesprong teams in the UK, France and Germany aim to create the momentum needed for stakeholders to act and for solution providers to invest in offsite manufacturing.
Planning department requires unchanged street scene
In Maldon the solution provider has had to meet an additional requirement from the local planning department to keep the exterior facade of the properties unchanged apart from the solar PV. The chimney and dormer windows to the front have therefore been retained.
Jason Amos of Moat explained “Because both of those overshadow the solar PV, they have an impact on performance… so, from a solution point of view you’d want to lose both, but, from an architectural and street scene point of view, we needed to retain them.”
To keep the looks the same, solution provider ENGIE opted for acrylic brick-effect external insulation panels from Mauer. These have been colour-matched to the brickwork they cover. ENGIE also replaced the dormer windows to the front (Velux to the rear) which are highly insulated, triple glazed, and (being slightly larger) let in plenty of light.
Stuart Moore of ENGIE said that he was impressed with the durability of the insulated wall panels compared to brick slips. He explained how the insulated corner panels integrate seamlessly and how great care has been taken to avoid any cold bridges within the design and fitting of the 200mm roof and wall insulation and the 300mm underfloor insulation.
Site visits are an opportunity to share progress and experiences
Site visits have played a vital role in convincing potential stakeholders of the merits of net zero energy retrofit. These are an opportunity for hosts to share their progress, plus the challenges of delivering retrofit to this exceptionally high standard. Coach trips to the site took place on 7 March and 23 May, with a further visit booked for 27 June.
The Maldon site visits have been hosted by leading housing association Moat, solution provider ENGIE, insulation panel manufacturer Mauer and the Energiesprong UK team.
During the Maldon site visit on 23 May there were formal presentations and further Q&As by Jason Amos of Moat and Stuart Moore of ENGIE. This was an opportunity for knowledge sharing and more detailed answers, including helpful figures and statistics.
Besides Maldon, there have been over a dozen formal visits to the UK’s first Energiesprong pilot in Nottingham supported by E=0. In December work began on a new 17-home E=0 supported pilot in Nottingham as part of the Energiesprong rollout there to 155 homes.
Watch a short video of the first Maldon Visit here.