Can a period house be energy efficient?
In the first of two articles, Gillian Livingstone and Richard Williams describe their experience of improving the energy efficiency of their 17th century cottage.
In March 2022, we moved into a 17th century weavers' cottage, a Grade II listed building. As the purchase neared completion, it became clear that listed properties were EPC exempt and we therefore had no opportunity to assess the energy efficiency of our investment. The certificate gives an energy rating (A-G) based on the nature of the building (including walls, roof, floors and glazing) and its services, such as heating, ventilation and lighting.
Historic England justifies the exemption given to listed buildings on the grounds that compliance with specific minimum energy performance could 'unacceptably alter their character or appearance' So, planning permission for double glazing or solar panels would be unlikely. Its website, however, does provide useful information on how to improve the energy performance of older buildings. In keeping with the distinctive nature of historic buildings, it recommends a 'whole building approach' which explores the specific nature of the home, looking at how it has evolved over time and how it works as a living space.
This is what we aim to do in this piece, with the proviso that what works for us may not work for other people. We hope you will enjoy our journey and benefit from our experience.
According to the EPC guidelines, buildings are responsible for almost 40 per cent of the UK's energy consumption and carbon emissions. We have always tried to live sustainably, aiming for minimal impact on the environment. Just after moving, we followed up an offer from the Town Council and Climate Friendly Bradford to assess the efficiency of our home, and as a result were oftered a free thermal imaging survey.
The survey, which involves closing all the openings and drawing cold air through the house, checked for air leaks and poor insulation. The results were encouraging. There was modest heat loss through the window frames and ventilation vents but, overall, the building appeared well insulated. We responded to the feedback by creating a door curtain, placing rugs on the wooden floors and inserting a finer mesh in the vents.
We were not surprised that the building appeared well insulated. The walls are of solid stone construction and the small footprint over three storeys allows heat to circulate throughout the property. Previous owners had laid quarry tiles and flagstones in the ground floor and fitted blinds to most of the windows. The central heating is supplemented by a woodburning stove in the front room. In the kitchen, two Velux windows not only draw light into the extension at the back of the house but also provide solar gain during the day. A Rayburn cooker, now over 25 years old, is our main source of cooking and contains a back boiler which heats our water for domestic use and central heating. If anything, the house is too warm.
The problem mostly lies with the antiquated Rayburn where the gas supply is always switched on. The heat it provides in winter is welcome; in the summer it is too much. It also wastes energy and elevates our heating bills. The system accrues deposits from the local hard water and at a certain temperature creates a phenomenon known as kettling, which sounds like a poltergeist seeking to escape the pipes and is generally unnerving in an older house. To prevent the sound effect, we calibrate the heating temperature to below 60 degrees but the low temperature of the water circulating the heating system is less efficient.
As a result, we use the central heating sparingly in the winter and turn to the wood burning stove. We have swept the chimney and use only kiln dried logs from a local provider, but we are aware burning wood contributes to particulates in the atmosphere, even in a rural setting.
We considered some options.
We first researched replacing the wood-burner with an Eco-stove which would circulate warm air throughout the house, and thus reduce the need for central heating. The Eco-stove company were very helpful and provided detailed recommendations based on information about room sizes and the chimney space which we provided. However, the problem with the hot water remained unresolved and at around £9,000 for the smallest size, we felt it was too expensive.
It is an option we may return to later.
Bombarded on social media by offers of government grants and business recommendations, we considered installing a heat pump. A representative from Transition Bath gave a useful and informative presentation which explained the practicalities. We decided there were too many drawbacks. The appliance needs to be fitted to an outside wall and can be noisy.
Since our house is one of four properties which back onto a shared communal space, this was a serious disadvantage. The heat pump operates at a lower temperature, where the capacity of the radiators is key; in many cases, they will have to be replaced, a further expense. Finally, to apply for a grant, the property needs to have an EPC... In the end, we decided to convert our gas-fired system to one based entirely on electricity. While we realise electricity charges are more expensive, we will now have only one standing charge; we hope in time with greater reliance on renewable sources and as a consequence, better energy security, prices will come down. We have recently switched to Octopus Energy which has a wide offer of flexible tariffs.
The wet central heating system will be replaced by electric radiators, which can be placed sympathetically to reflect how we use the room. The radTherm unit radiates heat from a ceramic core which reaches the required temperature after 12-15 minutes, per hour of usage. Individual thermostats can be adjusted manually (or through an app) to control the temperature room by room. We plan to replace the old water tank with a Sunamp Thermino thermal store/heat battery, which stores heat and will produce hot water on demand. The unit is more compact than the original tank and we look forward to more storage space in the airing cupboard.
In our research we approached two companies, who provided a similar offer: their details are listed below. Both companies sent representatives to our house where they surveyed our current system and gave informed advice on the choice of products available. For example, we learned that radiators in a conservatory do not meet current building regulations because of heat loss. We went with the more local provider, Cotswold Heating Solutions, who at just over £10,000 came out slightly cheaper.
The Rayburn cooker will also be converted to electricity so we can keep our characterful cooker and stay in the kitchen. The conversion kit will be installed by Hampshire Cooker Conversions and will cost around £2,400 including VAT.
We plan to implement these improvements over the summer. We hope we will see a difference in the overall energy efficiency, a more comfortable ambient temperature and lower energy bills. We will report back in the next edition of the Guardian Angel.
