SuperHome Database

Bristol, Carnarvon Road

House Summary

Chris and Ilsa Preist
House Type:
6 Bed Victorian semi detached
Carbon saving:
61% - SuperHomes Assessed  
Bristol Green Doors

Measures installed:

  • Condensing boiler
  • Double Glazing
  • Draught-proofing
  • Floor Insulation
  • Internal Wall Insulation
  • Loft Insulation
  • Low Energy Appliances
  • Low Energy Lighting
  • Mechanical Ventilation Heat Recovery
  • Roof Insulation
  • Solar Water Heating
  • Water Saving Devices
  • Wood Stove

  • Front Facade_Carnarvon Road
  • Internal wall insulation_Carnarvon Road
  • Kitchen_Carnarvon Road
  • Chris

Upcoming events

Early interest in Open Days encourages SuperHome owners to host more events. If you'd like to visit this property please contact the owner and let them know. SuperHomers are often happy to respond to questions about their refurbishment project by email between times. Please read ‘more on contacting this SuperHomer’ before you make contact.

Personal story:

I live with my wife Ilsa, our son Jed and daughter Mira in this house in Redland. We moved here in 2011, and had the work carried out prior to moving in. Ilsa is a glass bead and beadwork artist, working from her workshop at home. I am an academic at the University of Bristol.


We were primarily motivated by the desire to reduce the environmental footprint of the family by saving energy in the home, with a secondary desire to protect against raising energy prices.

Property background:

Before the refurbishments this Victorian semi-dethatched house was prone to drafts and damp. There was certainly a temperature gradient in the house and it was difficult to keep warm and would have been expensive to heat. However, we were attracted to the property due to its size and location, as well as its garden.

Key changes made:

Combination of solid wall insulation, good airtightness and mechanical ventilation heat recovery system means a good even temperature and good air quality through the house.

Measures installed in detail:

  • Vaillant EcoTech Plus 624 condensing gas boiler (91.2% efficient). Time and temperature zone control, weather compensation
  • Double glazed timber framed sash windows, 20mm gap and argon filled (U = 1.70)
  • Air pressure test 5.05m3/hr/m2@50Pa after renovations
  • 200mm Knauf Roll44 floor insulation in most of main house (U = 0.17). 100mm Quintherm in extension solid floor (U = 0.17)
  • 70mm Quintherm internal wall insulation applied internally to all external walls (U = 0.25)
  • 300mm mineral wool loft insulation
  • Low energy appliances include A++ fridge freezer
  • Low energy lighting includes CFL and LED lighting throughout
  • Villavent Whole House Mechanical Ventilation Heat recovery system (VR 700 DC)
  • 70mm Quintherm (PIR) rigid insulation boards (U = 0.13) in loft, boarded over. This is equivalent to >300mm mineral wool. Equivalent in roof of loft conversion. Stud walls here insulated with 80mm Quintherm (U = 0.26)
  • Vaillant AuroTherm evacuated tube solar water heating panels (4.6m2 flat plate) with solar powered pump linked to 300 litre combined solar cylinder with full pipe insulation
  • Water saving measures include a low flush toilet
  • Wood burning stove (closed log burner for secondary room heating)
Benefits of work carried out:

We were pleasantly surprised by the improved comfort level of the house due to a more even temperature throughout, with no hot or cold spots. The house is easier to heat as all the drafts are taken care of. There are lower humidity levels in the house which has taken care of the damp problem and improved the air quality which probably has a positive effect on our health.

The double glazing has reduced the amount of noise from the street and has increased the value of our house. The LED lights are very good – as good as the halogen lights and there has definitely been a change in our energy bills.

Another aspect of the refurbishment that worked particularly well was the preservation of the interior features despite the fact that we had internal wall insulation – we put it down to good contractors!

Other people around here complain like mad in the winter whereas we don’t. Other houses like this one suffer from a lot of problems. We definitely prefer our home now due to a combination of the fact that it is more comfortable to live in and that warm fuzzy green eco feeling.

Favourite feature:

The feature from which we get the most satisfaction is probably the insulation because the house now feels a lot warmer.

Common questions and answers for this SuperHome

Should we double glaze or draught proof our sash windows or do a mixture of both?+

We considered draught proofing and replacing just the panes with thin double glazing, but in the end went for full replacement of them with period style windows made by our contractor. They did a very good job.

Of all the things we did, this was the least cost-effective from an energy saving perspective. We estimated a 40 year payback time from fuel bill savings… However, it is the most easily understandable for buyers, so is likely to increase the value of the house, and also reduce noise a bit.

As it was, the wood of the original windows was suffering a bit, so full replacement had other benefits. But if this wasnt the case, then I think really well draught proofing it would have been the best from a cost-benefit perspective.

What contractor did you use for your eco-retrofit?+

Unfortunately, our contractor no longer exists as a business, even though they did a very good job for us.

Contact this homeowner

Assessment types

SuperHomes Assessed

A home that has been visited and assessed by us and confirmed as reaching the SuperHome standard, which demonstrates a 60% carbon saving.

Homeowner Reported

Information has been provided by the homeowner about their home and energy use prior to the installation of measures and following their installation which demonstrates a carbon saving. This information has not been verified.

Remote Assessed

The homeowner has provided information on their home including what measures have been installed which has enables an assessor working on our behalf to assess their carbon savings. This home has not been visited to verify the measures installed.


This home has not been assessed, but the homeowner has reported what measures have been installed. It may be that this home is awaiting assessment.