SuperHome Database

Winchester, Colden Common, Piping Close

House Summary

Rob Veck

House Type:
1979 Modern four bed house

Carbon saving:
86% - SuperHomes Assessed  

Reported saving on bills:

Total invested:
£62 000 (in 3 phases)

  • IMG_1503

Measures installed:

  • Ceiling insulation
  • Condensing boiler
  • External Wall Insulation
  • Floor Insulation
  • Loft Insulation
  • Low Energy Lighting
  • Mechanical Ventilation Heat Recovery
  • Rainwater Harvesting
  • Reclaimed Materials
  • Solar PV Panels
  • Solar Water Heating
  • Triple Glazing
  • Water Saving Devices
  • Wood Stove

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.

What visitors are saying

"We are already very concious of the impact we have on the planet. We were looking for the true 'next steps' and this house has certainly shown us them."

"Good insight into what sort of payback could be expected from the various projects."

"Very informative host who shared the motivation for the work then detail of how the work was done."

"A very informative talk with lots of facts about how they improved their home backed up with many visual aids and diagrams."

"It was excellent - I learnt so much! I discovered how to do things better than I had planned, to save money on my projects and new ideas - amazing experience!"

Personal story:

My name is Rob Veck, and I am a qualified project manager by profession. At the beginning of 2008, I had finished a major project at my company, and more of the same was on the horizon. A number of key personal events impact our lives and I asked the question “What is the compelling reason to give another year of my life at work?”  The pension fund was still in good shape, and at that time I finished Richard Heinberg’s book “The Party’s Over” (a scary book relating energy to human population growth – what goes up…). It was time for a change, so I took early retirement. I decided to undertake a new challenge to reduce the carbon emissions and energy footprint of our house as close to zero as possible, and document the whole experience (which is still ongoing). Additionally, I joined the village Greening Campaign and Winchester Action on Climate Change. Hopefully, we have succeeded in significantly reducing our CO2 footprint and energy consumption of the house – the journey continues!

In 2018 we suffered a major leak from our water tank located on the second floor, which required the inside to be completely gutted, dried and rebuild. We suspect the leak was due to the solar hot water providing too much heat to the tank causing the cold water feed to come off.

The water tank is now on the ground floor.


Our goal was to reduce our CO2 and Energy consumption by 80% and our motivation comes from the following:

The Kyoto agreement is to reduce emissions by 80% in 2050.

Heating accounts for 47% of the UK’s CO2 emissions and 60% of average domestic energy bills

The Heat and Energy Saving Strategy consultation document proposed the following goals :-

2015 – all lofts and cavity walls insulated
2020 – seven million homes to take up a “whole house” package going beyond simple insulation.
2030 – all buildings to have received such a package

Property background:

I purchased this 1979 modern 4 bed house in 1984.

Key changes made:

• Loft Extension 1989.
• Refurbished kitchen 2000.
• Refurbished toilets and bathrooms + condensing boiler 2006.
• Ground floor extension 2009.
• New drive with rain water harvesting tank 2013.
• Kitchen upgraded to include under floor insulation 2013.
• Internal completely refurbished in 2018/2019.

Measures installed in detail:

  • Ceiling insulation – Energain panels in 2 rooms to enhance thermal mass for loft extension.
  • Condensing gas boiler – all radiators with smart TRVs
  • External wall insulation (Celotex) based on rain screen cladding with a U value of 0.14 W/m2K.
  • External wall insulation on extension – 200mm celotex onto solid wall 212mm thick concrete blocks. Use of 10mm of Spacetherm (aerogel) on window edges and lintles. Rest of house: 110mm insulation (note: cavity wall insulation already in place)
  • Floor insulation – 165mm Celotex under floor (except down stairs WC). Polystyrene panels for extension to achieve a U value of 0.10 W/m2K
  • Loft insulation – 290mm Celotex on sloping roof and additional 150mm celotex on flat roof of dormer. Additional 200mm on dormer walls (with 100mm glass fiber insulation already in place).
  • Low energy lighting – 80% of lights replaced with LED 1watt GU10 bulbs
  • Mechanical Ventilation heat recovery – Villavent system
  • 3.85kWp PV System; 22 BP 4175YT panels wire in 4 strings
  • Solar hot water – Navitron SCM15-58/1800
  • Triple glazing installed in dormer windows and extension. New front & back door from Green Building Store with a 0.8 U value
  • Water saving devices – dual flush toilets, rain water harvesting
  • Contura Wood burning Stove
  • Excess heat convected from stove to master bedroom
  • Recycled flooring & decking for back garden
  • Halstead 3500 litre rainwater harvesting system supplying washing machine, 2 toilets and gardens
  • Charging point installed for electric vehicle. Electric vehicle in combination with a low carbon source of electricity (Ecotricity claim 0g/kWhr as all their electricity is from renewables) is a contributing factor to lowering CO2 footprint
  • Allotment: Requires an investment of time. Using “no dig” approach to nurture the soil, reduce time in weeding and general maintenance. Aiming to become self sufficient in vegetables, and hence reduce / eliminate food miles
  • Buying local
Benefits of work carried out:

Heating is provided by wood burning stove and is sufficient to fully heat the whole house.
Only requires 1 delivery of wood per year (£150).
Central heating was on for 1 day in 2012/13 winter.
Low energy costs (surplus income when taking into account feed in tariff.)
Approx 5% ROI index link.
Carbon footprint significantly reduce (80%+) and even lower with renewable energy supplier (all energy produced is at 0g per kWhr).

Favourite feature:

Wood burning stove.
Extension that opens onto the back garden.

Project update:

Due to a large leak, the house was extensively refurbished over 12 months. The key changes were to relocate and install a new boiler to the ground floor, upgrade the heat recovery system with more efficient pipework, and the replacement of the wood burning stove to is also a heat store.

The previous Hwam wood burner was also quite efficient and in hind site, we should have simply replaced it and improve the quantity of concrete in which it was embedded.

We now have 10 years (2010 to 2020) of weekly data on and as of 17/11/20, CO2 emissions for 2020 is 986kg (not including what has been burnt with wood). Total of 4077 kWh.

Common questions and answers for this SuperHome

Is there a risk of interstitial condensation with external wall insulation of a U value better than 0.5 on a home with cavity walls?+

Rob’s Building & Environmental Consultant, Ken Neal, answers this question thus.

Interstitial condensation occurs where the dew point falls within the construction thickness.  This will almost always be the case in cold weather.  Where this occurs and in what material is where the problem can lie.  With a badly insulated structure the dew point will form close to or at the inside face of the construction causing damp and this then causes harmful mould growth.  With a well insulated structure the dew point is well into the construction depth and so there is less of a problem with dampness and mould growth at the inner surface.

This can cause a different problem, though.  If the outer surface is a soft porous material such as old brick and the weather is freezing the interstitial condensation occurring in the outer layer of brick can freeze and spall off the face of the brick.  This can happen with cavity insulated structures or with internally insulated structures.

With the external insulation system that I specified for Rob’s improvements the dew point falls well within the outer layer of insulation.  Because of the make up of the insulation material the moisture vapour cannot move through the insulation to the dew point so it stays warm and in the form of vapour.  Where the vapour moves through the joints between the boards there can be condensation but it is harmless and drains away eventually.  Any other excess vapour is removed from the house by the ventilation system accompanied by the low level of heating required by the highly insulated structure.

Internal insulation systems commonly used in older and listed properties have to be very carefully specified and detailed to prevent the occurrence of cold bridging and moisture movement through the insulation.  This is to prevent the build up of moisture in the outer layers of the construction and possible freezing damage.  These insulation systems, while being possible to construct on a DIY basis, need to be properly designed and detailed by an “experienced” professional to avoid the many pitfalls that can occur in a badly designed and detailed  job.  A DIYer has as much experience as many builders in this type of construction and are more likely to follow the plans and get it right than many builders who will do it the way that they have always done it and get it horrendously wrong.  There needs to be a huge educational push in the building industry to show most builders how to work with modern insulation materials.

I have not read the ‘Breaking the Mould’ report and if it cautions against U-values of less than 0.5 I am not going to bother.  U-values of around 0.1 are commonly used on the continent and occasionally used here, as was the case with Rob’s house, without any problems.  Where problems can arise are when systems are not properly designed, detailed and built.  That is not a problem with high levels of insulation but with bad building.  We need to address bad building not the required high levels of insulation.

A house with a best insulation value of 0.5 is more likely to suffer damp problems than one with a better U value because the cost of heating such a structure will mean that it is often colder than it should be, inviting surface condensation and mould growth.  It will often be kept more airtight to avoid cold draughts and hence build up a higher level of water vapour within the structure.  Such a property would commonly have double glazed windows which will prevent condensation on the glass.  This will, however, throw more water vapour onto the cooler walls exacerbating the mould problems.

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.