The following information is referenced from the Retrofit options study of a ‘typical’ home in Letchworth report, conducted by People Powered Retrofit for Letchworth Garden City Heritage Foundation (April 2025).
Some of the approaches featured in the Interactive House may at first seem daunting. We know many people want to get moving as soon as they can on making improvements to their home. Here we’ve provided a list of some simple things you can do that will make an immediate difference, though often a relatively small one.
Building maintenance
Check and clean gutters and rainwater downpipes to avoid making your walls wet and cold through leaks. Unblock air-bricks that provide ventilation below suspended timber floors and check ventilation paths in your attic or cold loft space. If you live in an older building, the SPAB provide useful guidance on carrying out better building maintenance, and even have an annual ‘Festival of Maintenance’: spab.org.uk/news/maintenance-win-more-sustainable-homes.
Lighting
Upgrading lighting can make a big difference to energy efficiency but also the look and feel of your home. In most cases you probably don’t have old-style incandescent light bulbs, having replaced them with compact fluorescent lights or halogens – but you can make further improvements by replacing these with highly energy efficient LED lighting. This gives you more light output for every watt used. The light is also often better quality – with a range of colour temperature choices also available – https://energysavingtrust.org.uk/advice/lighting/.
Appliances
Replacing old kitchen and laundry appliances with the most efficient model you can afford when replacement is required will help reduce your energy use. Look for the energy rating when buying new and replacement appliances. The amount of energy needed by appliances is also dependent on your behaviour. The Energy Saving Trust produces useful information on this: energysavingtrust.org.uk/advice/home-appliances/.
Cooking
Straight forward changes like putting lids on pans when cooking and making sure you switch off fully can help cut your electricity bill. If you currently cook using fossil gas, you can replace this with an induction hob and an electric oven. This will improve energy efficiency and remove your reliance on fossil fuels, whilst also improving indoor air quality within your home. If you have switched to a heat pump this may also give you the opportunity to remove your gas supply altogether – and so avoid the standing charge for this fuel in future. You can find a useful article about this here: ethicalconsumer.org/home-garden/shopping-guide/gas-electric-cookers.
Heating system and controls
Spend some time properly checking how you use the controls for your existing heating system, so that you are using it effectively and efficiently. The Centre for Sustainable Energy publish useful video guides on this: cse.org.uk/advice/advice-and-support/central-heating-controls and cse.org.uk/ advice/advice-and-support/night-storage-heaters plus other links in the same place for different systems.
If you have a central heating system with a condensing boiler, you may also be able to adjust some of the settings on this to make it work more efficiently. You can find out more about this in this useful guide published by the Heating Hub: https://www.theheatinghub.co.uk/articles/turn-down-the-boiler-flow-temperature.
If you have an electric shower, but plan to move to a heat pump-based heating system in future, it’s worth considering replacing this with a mains fed shower as part of your plans as this should reduce overall energy use. Check water flow when you do this – low-flow showers that require less water to be heated will always be more energy efficient.
Ventilation
Make sure your home’s existing ventilation system is in good working order. Clean dusty fans and make sure windows are openable and not painted shut. Make sure you use your system, by switching on cooker hoods and bathroom fans when you need to. This should improve the air quality in your home.
Laundry
Clothes should dry in a place that is well ventilated and has some heating. This is so that they dry quickly and the moisture doesn’t stay in your home. Drying clothes outside is best if you have space – though given the climate of the UK that is not always possible. Avoid drying clothes on radiators as this makes your radiators less efficient. If you have a hot water store or cylinder, or plan to add one, the space this sits in is a good place for drying clothes, as it makes use of waste heat. If this is near a ventilation extract to a bathroom or utility space, that’s even better. The University of Glasgow have published a useful guide on clothes drying available here: https://radar.gsa.ac.uk/2700/1/MEARU_Laundry_Design_Guide.pdf.
Using renewable energy
You can maximise your savings from existing renewable energy systems by using more of the energy generated directly in your home, instead of exporting it to the grid. Adapting your habits, for example by using your washing machine when it’s sunny, or using a slow cooker during the day, can all help. Adding storage for the energy you produce is also possible. If you have a hot water cylinder or store, it’s often possible to fit a ‘PV diverter’ for a few hundred pounds that helps you make use of excess energy to create hot water.
Monitoring
Monitor your existing energy use in detail, so that you understand where energy is going and can potentially reduce it through changes in your patterns of use. This can be as easy as checking your smart meter data or taking more frequent meter readings. It can also be useful to monitor the environment in your home, especially its temperature and humidity. This can also be done very simply with a small battery-powered hygrometer/thermometer and a notepad, or you can use more advanced monitoring.
To see an extensive list of retrofit measures, please view the Interactive House.
Note: Since 2022 the Building Regulations have applied to existing homes too – you can find out more about this here: https://www.youtube.com/watch?v=_jQ3ZxOLH1o.