Late Regency home in Conservation Area

CONSTRUCTION – A 4 bedroom end terrace Regency house located within a conservation area of Cheltenham. Built in 1840 with thick solid brick walls, it was extended very soon after at the gable end to create an additional 3 storey area that has a wall that curves from the front to the new gable end. This wall is much thinner than the original walls which made this part of the home colder than the rest of the house. When the current owners moved in they found that the house was very energy inefficient generally with an old heating system, single glazed windows and a large number of energy hungry halogen down lighters.


Internal wall insulation – improved thermal comfort and heat retention

Double glazing and window shutters – improved comfort and elimination of draughts

Condensing boiler & heating controls – bills reduced by an estimated 40%

1.57Kwp solar PV – around £580 a year saving

Low Energy & LED lighting – up to £200 a year saving

Energy Rating improved from F to C

With a keen interest in the environment, and a determination to live more frugally in regard to energy, the owners took on a number of home improvements that they hoped would improve the energy performance of their home as well as making it a warmer and more comfortable place to live.

They have transformed the home, reducing energy costs and carbon emissions by up to a half and increasing the EPC rating to a C. This investment, at a cost of around £38,000 has provided them with a home that is ‘much nicer to live in’ as well as being much cheaper to run. There are still a few challenges, such as insulating the floor in the basement, but the owners now feel that they have got to the stage where they have done most of what they can and are enjoying the benefits.

If we could offer one piece of advice, it would be to make any big capital improvements before, or soon after you move in If possible. This will  reduce the disruption that work such as glazing and internal insulation can make.

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Glazing solutions

The biggest investment made by far was to replace all but two of the original, draughty single glazed windows. New individual bespoke double glazed units were made and fitted that were sympathetic to the original windows, and in keeping with the conservation characteristics of the area. These not only made the house feel warmer but also reduced noise levels from outside. The two remaining windows, one of which was curved and so difficult to replace had shutters built for them that can be closed in the colder winter months helping to keep the warmth in.

Improving the heating

The old inefficient heating system was unable able to heat the house sufficiently so a new condensing boiler with a programmer and thermostat was fitted alongside a wood burning stove sited in the main living room. Adding doors from the living room to the rest of the house was a huge help in allowing the owners to quickly heat the living room when necessary by keeping the doors closed, and then opening the doors to allow the heat to escape and heat the rest of the house when it became too warm!

The new boiler has ‘paid for itself’ within a few years the owners commented.

Solar PV

The householders had three distinct reasons for considering the addition of solar PV panels. Not only were they hoping to reduce their carbon footprint, but the investment should also reduce their energy bills and provide them with a good return on their money. A 1.57 Kwp system was installed in 2010 on their rear east, to south east facing roof space. With the benefit of a partial grant toward the cost and generous payments from the ‘Feed In Tariff’ scheme the owners are expecting a 12% return on their investment, typically earning over £500 a year in feed in tariffs and saving around £80 a year on their electricity bills by using the generated electricity. The owners also commented that cost should not be the only consideration when selecting your installer. They obtained three quotes and chose the installer they felt had the right knowledge and experience to best help them.

Interior wall insulation

As well as being thermally poor, the curving extension wall is on the north facing side of the house which made this part of the home very cold in winter. Even with a newly insulated loft, heating system and double glazing, improving this area was now a priority. External insulation was not possible due to planning constraints and typical solid board internal insulation not practical due to the curving wall and limited room in the kitchen.

‘Warm a wall’ which is a flexible, thermal and acoustic wall lining made from recycled polyurethane was chosen to insulate these north facing walls as an alternative. This was applied over the existing wall and then re-plastered and decorated. Although this was a time consuming and disruptive job, the rooms are ‘noticeably better’, bringing ‘big benefits in comfort’.

Low Energy lighting

At the time of moving into the house there was not a single low energy lightbulb to be seen, even though there were 75, 50watt downlighter halogen bulbs! The owners estimated that the lighting costs alone would amount to over £200 a year. They set about replacing the bulbs with traditional low energy versions and replacing all the downlighters with LED versions that use a fraction of the energy of halogens and last a lot longer. Even though most of this work is now complete and they are using far less electricity to light their home the owners highlighted that ‘they only use what they need, and switch lights off after use!’