1935 EnerPHit extension and retrofit - Oakington

1935 EnerPHit extension and retrofit – Oakington

Sat 15 Oct 2022, Various

Meet your hosts, Philip and Rachel

When Philip and Rachel decided to renovate their home, they did so with the environment front of mind. They purchased their home in 2018 and quickly got to work with EcoDesign Consultants to devise a plan to add a two storey extension and retrofit their house to the highly insulated and airtight PassivHaus building standard. They started the work in 2020, and hope it will be completed by autumn this year. Already they’re feeling the benefits, with their home now keeping a steady temperature year round with only minimal heating needed in the winter. Their energy use has dropped by nearly 90%.

Rachel says:

 “We’ve always been environmentally conscious and we knew when we bought the house that it would need substantial work to make it a 3 bedroomed family home. We kept trying to work out a way to do it in stages but there was always a ‘chicken and egg’ issue, which meant it made more sense to try and do everything at once. We realised that we needed to treat the house as a whole system to get the full benefits of making it energy efficient. Having a warm roof didn’t make sense if we were losing large amounts of energy through the windows, for example. We also picked suppliers and manufacturers that fitted with our ethics and where possible, used recycled materials. 

It was also important to us that the job was done well and would last, as it’s not eco to be re-doing the work 5 years down the line.”

Case Study  with lots of useful links to suppliers and Contractors that Philip and Rachel used

Key Features of this home

  • Replaced a single storey extension with a 2 storey extension to passivHaus standard
  • Replaced roof, now a warm roof with 100mm of phenolic board and 100mm of rockwool
  • Insulation underneath the concrete floor slab with 200mm of phenolic board
  • External wall insulation
  • Cavity wall insulation in the new extension
  • House has been made air-tight with a mixture of membranes and renders
  • Mechanical ventilation and heat recovery (MVHR)
  • Air source heat pump with underfloor heating downstairs and oversized radiators upstairs
  • Solar PV array
  • Airtight PassivHaus rated triple glazing throughout
  • Soakaway for surface run-off water
  • A rated efficiency appliances and LED lighting throughout.
  • Wildflower meadow in the garden

Tour details

1 hour in-person tour with a maximum of 8 people per tour, running:

  • Sat 15 Oct, 11.00am
  • Sat 15 Oct, 1.30pm
  • Sat 15 Oct, 3.30pm

This is an in-person tour. Location details will be sent in a confirmation email upon booking. Tour spaces are very limited. Babes in arms and young people (14+) are welcome.

Book your in-person tour

Standard entry is £5/person to help us cover our costs and help us run more Open Eco Homes tours in the future. Please email bookings@openecohomes.org if you’d like unpaid entry for this event.

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Thanks to our 2022 Open Eco Homes funders and supporters

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