Recent news articles have suggested that by 2025 we may not be able to buy a new gas boiler to replace a failing one. So the question all homeowners need to be thinking about is, “How will we heat our homes when mains gas is no longer an option?”
Homes built in more recent years have sufficient insulation and draught proofing for homeowners to switch to electrical heating systems, like heat pumps. Eventually building standards must be altered to deliver zero carbon homes (the UK government’s target date for this has been pushed back to 2025). Once this occurs, homes are expected to be built with Mechanical Heat Recovery Ventilation (MHRV), allowing ventilation with little heat loss in a well-sealed house. Zero carbon, Passivhaus type homes typically require only 3 kilowatts of heating!
For older housing stock, for example a three bed house, currently a plumber will typically recommend a 20 to 30 kilowatt gas boiler. Switching this sort of home to electric heating, utilising the existing radiators, is likely to require so much electricity that the house would need a 3 phase power supply, particularly if you will also want to quickly charge an electric car!
The reality is we need to substantially improve the insulation and draught proofing of the majority of homes before we can install affordable electrical heating systems. MHRV systems are difficult to retrofit, as air ducting systems are needed linking all the main rooms including kitchens and bathrooms. So once you’ve got high quality double glazed doors and windows, it’s almost impossible to further improve the draught proofing of typical brick and block built housing. It is currently difficult to retrospectively improve the insulation of existing housing stock. Internal cladding uses up internal space and condensation can be a problem as the dew point moves to a point inside the brickwork. External cladding affects the appearance of properties, and in Letchworth, the Letchworth Heritage Foundation design principles have proved to be so restrictive that, to date, Transition Town Letchworth members interested in improving their homes have been unable to identify external insulation solutions that would meet the design standards.
If the government is aiming for a zero carbon economy, it has to close down coal fired power stations and turn off mains natural gas. To be able to do this it needs to raise the quality of housing stock across the whole country in order to reduce energy demand. The government strategy is likely to take a ‘carrot and stick’ approach. A ‘carrot’ may consist of energy saving grants. A ‘stick’ could for example be legislation stopping the sale or rent of homes that aren’t up to standard. What will this do to the demand for, and hence value of the older housing stock?
Transition Town Letchworth have persistently lobbied the Heritage Foundation … to find and agree affordable, acceptable external insulation solutions, but with no success to date. Our hope is that the message that gas boilers may be banned by 2025 may be the wake-up call … to prioritise finding external insulation solutions. If this doesn’t happen soon, then we expect that many homes will fall into ‘housing delinquency’ with owners unable to cost effectively update and heat their homes.
Given that the vast majority of homes are presently heated by gas, we are hopeful that the urgency around tackling climate change, an urgency accepted by most councils, housing associations, developers, landlords, tenants and home owners, will drive the delivery of lower cost insulation and renewable heating solutions alongside changes to building regulations. This would allow us all to embrace the demise of the gas boiler.