Improving the energy efficiency of your home

Save money on bills and help prevent climate change through more efficient use of energy and by reducing waste.

Energy bills are rising steeply, so making your home more energy efficient is a good long-term investment. What’s more, almost half of the UK’s carbon dioxide emissions come from energy we use every day, much of it in the home. You can make a huge difference by being more energy efficient.

In June 2022, the government brought into effect new building regulations to ensure carbon dioxide emissions are kept to a minimum. These rules affect new-build homes and self builds, as well as anyone undertaking certain renovations, conversions or extensions of existing properties. 

To get you started, here are some things to consider...

Small, easy ways to be more energy efficient

Little changes can add up to make a big difference. A jacket for your hot water cylinder costs about £15 and will cut heat loss by more than 75%. If you already have a jacket fitted, check it’s at least 75 mm thick. You can also insulate radiators and pipes to help stop them losing heat. 

Another option is to switch to electricity from renewable resources and/or generate your own energy such as from solar panels (see below for more about eco-technologies). When you need to replace an appliance such as a fridge or kettle, look for the most energy-efficient models. And remember to turn off lights and appliances when not using them.


When you need to replace bulbs, choose energy efficient lighting that will save you money on bills. LED bulbs are the best option as they’re highly energy efficient. LEDs produce a negligible amount of heat, consume a fraction of the energy used by conventional bulbs and last up to 20 times longer – about 50,000 hours.

Draught proofing 

This is another simple way to make a difference. If you ever feel cold air getting in around your windows or doors, warm air is also escaping. In fact, some 20% of all heat loss from a typical home is through poor ventilation and draughts. 

A range of materials can be used to close up these gaps, from brushes, foams and sealants to strips and shaped rubber or plastic. You can also use a regular tube sealant such as silicon to fill gaps between floorboards and skirting boards. 

Warning: don’t block underfloor airbricks in your outside walls, as floorboards will rot without adequate ventilation.

Double glazing 

You can halve the heat lost through old or poor-quality double glazing by fitting new, high-performance windows. Always look for the energy label: A++ as these windows are the highest rating currently available, and installers must not now fit windows rated lower than B. For more information see the Energy Saving Trust’s guide to reducing home heat loss through windows and doors. 

Note that to comply with building regulations, new windows are usually fitted by a member of a relevant competent person scheme. If windows are replaced as part of a bigger refurbishment, your builder may be able fit them and include the work as part of the building regulations application so that your local authority building control team can inspect them and approve the installation.  However, if you are replacing windows you must ensure that either a competent person installs them or you make a building notice application to building control before you start the work.

Loft insulation 

This is a simple, effective way to stop heat loss and reduce bills. The insulation acts like a blanket, trapping heat as it rises from the home below and ensuring it doesn’t escape. 

It’s a fairly straightforward job to insulate a standard loft if you are confident of your DIY skills, but there are professional companies who will also do the work for you. 

Insulation of an existing property is carried out with mineral wool or other flexible materials that meet minimum energy efficiency values as set out in building regulations. This is laid between the joists (the horizontal beams that make up the floor of the loft), and then a second layer of insulation is added at right angles, to cover the joists themselves. This should result in the recommended 270 mm depth of insulation. 

If you have a flat roof or a converted loft, it may be more difficult to add insulation. A standard loft with limited access or headroom may also present challenges, but a specialist company should be able to help you. 

Cavity wall insulation 

Another of the most cost-effective improvement to the energy efficiency of your home is to fill the gap between the two layers of exterior wall. This can reduce heat loss - and costs - by more than a third. 

Note that not all homes have these “cavity walls”, and some have cavity walls that don’t suit this kind of insulation. In some cases, work may be needed before a cavity wall can be insulated, and/or a particular insulation material must be used. A certified installer can advise you on this.

Under building regulations, you need to notify your local authority building control team in advance of such work. If your installer is registered with the Cavity Insulation Guarantee Agency (CIGA), they will in most cases submit the building notice on your behalf — but always check they have done this on your behalf.

If your walls are not suitable for cavity insulation, you could consider “solid wall insulation” - see below. In fact, this can sometimes be the most appropriate option even if you have a cavity wall. 

Solid wall insulation

Solid walls lose more heat than cavity walls and the only way to reduce this loss is to insulate them on the inside or outside. This is more expensive than cavity wall insulation but you’ll save money on heating bills, it will help protect the fabric of your home and can even enhance the look of it. 

There are two types of solid wall insulation:

  • External insulation involves adding a decorative, weather-proof insulating treatment to the outside of your wall. This should be between 50 mm and 100 mm in thickness. External insulation is usually installed where there are severe heating problems or the exterior of the building requires some other repair work, too. You should check if you need planning permission and you will need to submit a building regulations application before you start this type of work.
  • Internal insulation involves lining the rooms of your home with material such as plasterboard laminates or wooden battens in-filled with insulation. These should typically be of total thickness up to 90 mm. Solid walls upgraded by the installation of insulation must meet minimum energy efficiency values set out in building regulations. Bear in mind that your walls will no longer be flush with your window and door openings which can leave cold spots where heat can escape. Consideration will also need to be given to how you will overcome this, either by adjusting the fixtures or adding further insulation around these areas.

Floor insulation 

Heat loss through suspended timber floor draughts can be substantial. They can be insulated by lifting the floorboards and laying mineral wool insulation supported by netting between the joists. 

Heating and hot water 

Boilers account for some 60% of all domestic CO2 emissions. A high-efficiency condensing boiler with heating controls could save you a substantial amount each year in bills, and significantly cut your home’s carbon emissions. As the current lifespan of a boiler is around 15 years, this can result in huge savings over time. 

Choosing the right heating system for your home can be complex. Design, location, orientation, shading and the fabric of your home all have an impact on any mechanical heating/cooling system. 


A range of options allow you to supplement the traditional energy supply from more renewable sources and are increasingly popular. 

These include solar panels (which either produce hot water or generate electricity), air and ground source heat pumps or generators, wood pellet/biomass boilers, log burners, wind and water turbines, and mini domestic combined heat and power generators. There are also mechanical ventilation and heat recovery systems (MVHR), and the latest generation of efficient gas boilers and smart control systems.

Some of these options are expensive, so you’ll need to consider the long-term return on investment. Other eco-technologies are very affordable, such as energy efficient domestic appliances and low energy lighting. So make sure you take time to do some thorough research before you go ahead.

For more advice on improving energy efficiency in your home and other home improvement projects, click here

Contact your local authority building control team here