SuperHome Database

London, Hackney, Culford Road

House Summary

Robert Cohen and Bronwen Manby

House Type:
1830 mid terrace 3/4-storey house

Carbon saving:
84% - SuperHomes Assessed  

  • London, Hackney SuperHome
  • Back View of Culford Road
  • UK Passivhaus Conf visit 11Oct10

Measures installed:

  • Condensing boiler
  • Double Glazing
  • Floor Insulation
  • Internal Wall Insulation
  • Low Energy Appliances
  • Low Energy Lighting
  • Mechanical Ventilation Heat Recovery
  • Roof Insulation
  • Solar PV Panels
  • Triple Glazing
  • Underfloor Heating

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

"This was very interesting and impressive to learn about energy conservation and efficiency and see how we can apply this in India. Robert and Bronwen were wonderful hosts and took the time to explain everything."

Personal story:

I am in the business as an energy consultant and my partner, Bronwen, is in the NGO sector.

I have co-authored two papers about the design and operational performance of the house which were presented at the International Passive House conferences in 2010 and 2012 respectively.


My motivation stemmed from a professional interest and from environmental drivers. I also wanted to see exactly what was possible to do to such a property in terms of increasing its comfort and reducing energy consumption. I’m obsessed about how much energy we actually are using, so I do keep track of that and obviously this is affected a lot by behaviour.

 When we bought the property it had central heating but apart from that it hadn’t been upgraded for a family to live in. It needed rewiring and re-plumbing as well as a new bathroom, kitchen and roof.

We set out to cut energy use by 80%. Our aim was to demonstrate that future generations can live in such homes without guzzling fossil fuels and that a hard to treat house can be transformed into a low energy dwelling as well as a delightful home.

Property background:

This mid terrace, 4 storey, 3 bedroom property was built in 1830. We bought the property in May 2007 and upgraded it in 2009, moving in to the house in January 2010. Due to the properties age and location it is subject to certain conservation laws and building restrictions, particularly on the front façade.

Key changes made:

The main changes made during the refurbishment included installing a lot of insulation and double and triple glazing helping to make the property airtight. We also installed underfloor heating in the basement and PV panels on the roof.

Measures installed in detail:

• 12kW Gas condensing boiler with 180 litres of hot water storage, controlled by a 7 day programmer, zone and cylinder thermostats
• Double glazed front windows using Slimlite in remade sashes, draught sealed, (U value 1.8)
• Floor insulation using 100mm of Polystyrene (U value 0.18)
• Internal wall insulation in the front of the property using 130mm of Knauf mineral wool  (U value 0.20)
• Rebuilding rear of property as a fully-filled cavity wall, with reused original stock bricks on the outside, 200mm thick glass wool and medium density thermal block inside, connected by low conductivity boronite cavity wall ties (U value 0.15)
• Low energy appliances include an A+ rated fridge freezer and an A rated oven
• Low energy lights include a mix of LED downlighters, fluorescent tubes, CFL pendants and CFL table lamps
• Whole house Mechanical Ventilation Heat Recovery system is 90% efficient
• Roof insulated ( U value 0.15)
• 1.32 kWp Solar PV (with feed in tariff) fixed to an unshaded flat roof, orientated  south east and tilted 10 degrees to ensure self cleaning
• Triple glazed rear windows with low E glass and double argon filled ( U value 0.9)
• Underfloor heating in the basement
• Insulated front door

Benefits of work carried out:

The house is very airtight so when the windows are closed there are certainly no draughts. I would say that about 90% of the time the temperature in the house is absolutely right. Except in very cold conditions, internal temperatures remain stable at around 20°C.  Even areas with no direct heating only fall below 18°C when external conditions fall below 0°C. The lowest recorded temperature in the upper ground area was 17.4°C during a week long sub-zero spell, due to the large spatial area and glazing. But even then it remains toasty warm in the kitchen and bathrooms.

The air quality is much better, the house is much more sound proof and there is a lot more natural daylight throughout. Our home security has also been improved by the refurbishments, which we realised when we managed to lock ourselves out one day.

Another benefit is the reduction in our energy bills.  In fact, we now have negative energy bills as we use so little energy and benefit from a feed-in tariff for our small PV system. Gas use in 2011 was 4,660 kWh (39 kWh/m2) of which 3,500 kWh (29 kWh/m2) was for space heating and the rest for hot water and cooking.  Electricity use in 2011 was 1,550 kWh (13 kWh/m2) of which 1,225 kWh (79%) was generated by our PV system. Total emissions for 2011 were 1.1 tonnes of CO2, an 84% reduction.

Favourite feature:

A combination of all the measures working together means that the house is very comfortable to live in. It’s only by doing everything that we’ve done, as a holistic approach, that we are now in a position where conditions in the house are so good. But if I have to say one thing that stands out, it is the daylight and sunshine that pours into all the rooms.

Business name:


Business overview:

Verco works on the eco- refurbishment of existing properties and the development of major new-builds. SuperHomer Robert Cohen is Technical Director. Verco (formerly Camco) has acquired considerable experience from the projects it has helped deliver:

  • helped set up The Existing Homes Alliance in 2008
  • produced a report  into Whole House Low Carbon Refurb to achieve 80% carbon reduction
  • advised public sector agencies associated with the exemplar low carbon development in Northstowe, Cambridgeshire
  • Ran award winning retrofit programmes in the South East (Retrofit for the Future and Retrofit for Reality)

Verco also provides software to help organisations monitor energy use (Carbon Desktop™) and manage their Display Energy Certificate (EPLabel).

For more information, see

Common questions and answers for this SuperHome

How long you have had your Slimlite double glazing units installed and have any of them have failed (misting up etc.)?+

We installed our Slimlite double glazing in 2009, after much research and debate. They are on the front façade only, six over six Georgian style, and had to satisfy Conservation Area scrutiny from the planners –  ie. no change in appearance from the front street. We tried to use the existing sash frames but our builder found they were not reusable – they were poor quality replacements of the originals anyway. Replacing the whole sash enabled us to get a much better overall result in terms of insulating the sash box and aligning it with the internal wall insulation to avoid cold bridging. Equally critical, we achieved air tightness with double seals on each sash (ie. inside and outside).

At the time we were making the decision, doubts were raised as to the long term argon gas retention capabilities of the Slimlite glazing units. Slimlite did not yet have the appropriate certification in relation to this aspect of their product although they believed that a loss of 1% per annum is likely. Their units had a guarantee for 5 years at that time, although some time before that their guarantee was 1 year only.

We went ahead realising the risk would be that at some point in the future we may need to replace all or some of the glazed units. That might be with Slimlite again, a future higher performing version of the Slimlite or another type of glass such the evacuated type.  So far, no failures, but we’re only at about the 4 year mark. I wonder if their guarantee remains at 5 years? And I have a gut feeling that smaller Georgian style panes might be less prone to failure, but that might just be optimism.

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.