0151 792 6245

Open Mon-Fri 8.30 to 5pm

How to reduce heat loss at home

If you want to be warm and cozy in the winter, whilst keeping your energy bills as low as possible, you need to reduce your heat loss. The last thing you want when you’re paying to generate heat, is to have it escaping out of your home as quickly as you’re producing it. But unfortunately, unless you look at ways to reduce your heat loss, that’s precisely what’s happening! In this blog we’ll give you some simple tips on how you can reduce your heat loss, which will help you to keep your warm air in, and the cold air out. This will not only keep you warm and comfortable but will help you to save money on your energy bills.

Share This Post

A piggy bank next to a pink scarf.Today we’re looking at how to reduce heat loss at home.

If you want to be warm and cozy in the winter; whilst keeping your energy bills as low as possible, you need to think about heat loss.

The last thing you want when you’re paying to generate heat; is to have it escaping out of your home as quickly as you’re producing it.

But unfortunately, unless you look at ways to reduce your heat loss, that’s precisely what’s happening!

In this blog we’ll give you some simple tips on how you can reduce your heat loss. This will help you to keep your warm air in, and the cold air out.

This will not only keep you comfortable, but will help you to save money on your energy bills too.

What is heat loss?

Like it or not, all buildings lose heat – and we’ve got science to thank for that!

It helps to understand the science a bit here. Because it makes all the tips on reducing heat loss make more sense…

The reason your home loses heat is because of the second rule of thermodynamics. Don’t worry – this isn’t as complicated as it sounds!

If you know that your cup of tea will go cold if you leave it for an hour; you’re already aware of this rule!

The second rule of thermodynamics says that energy (in this case heat); spontaneously disperses from being concentrated to becoming spread out if it’s not stopped from doing so.

At its simplest level, heat flows in one direction: from hot towards cold. This can happen through conduction, convection, radiation, or a combination of all three.

So, the reason your rooms heat up is the same reason they’ll also go cold. Warm air moves towards cold air.

This is great for us at first because it means that when our boilers pump hot water into our radiators; the heat will move towards the cold air in our room, making it warm – fantastic!

But once the air in our homes is warm, it will naturally want to move towards the cold air outside. All that lovely warm air that you’ve paid money to create, will ultimately escape out of your building. H

Heat loss is a measure of how quickly this happens.

Obviously, we want to slow this process down so that we can keep our warm air for longer. And not have to spend more money keeping the heating on.

Make sure you read our related blog: What is heat loss, and why is it important?

What are the benefits of reducing your heat loss?

Let’s take a look at what you stand to gain from reducing your heat loss:

1.    A more comfortable home

Nobody likes to be cold. But the more heat that escapes from your home, the colder it gets inside.

So, reducing your heat loss will help to keep you and your family warm and comfortable, whatever the weather.



2.    Reduced energy bills

Nobody likes wasting money, but when you have a lot of heat loss, that’s precisely what you’re doing. All the lovely warm air that you’re paying for, is quite literally running out of the building!

The faster that your heat escapes, the more you’ll have to use your heating to keep warm; and the more it will cost you.

By reducing your heat loss, you’ll be lowering your energy bills; because you won’t need to burn as much fuel to stay warm.

A woman pointing to the symbol for carbon.3.    Reduced carbon footprint

The quicker your heat escapes from your home; the more you’ll need to use your heating; and the more fuel you’ll burn.

When you burn more fuel, you are producing a lot of excessive carbon emissions which is responsible for global warming.

To reduce your carbon footprint, and slow the progression of climate change; you need to make your home as energy efficient as possible by minimising unnecessary heat loss.

How is heat escaping from my home?

To reduce your heat loss, you need to know how heat is escaping from your home. But this isn’t always easy.

Whilst you might notice a draught of cold air in a particular spot, most heat loss isn’t visible. And the amount you lose in different places might surprise you.

According to the Energy Savings Trust (EST), the following estimates indicate the proportionate heat loss from different parts of a badly insulated house: 25% through the roof; 35% through the outside walls; 25% through the doors and indows; and 15% through the ground floor.

The precise amount of heat loss you experience depends on a number of factors; such as the type and age of property you live in; as well as your altitude and exposure.

Generally, the older your building is; the poorer the insulation is likely to be; and the more susceptible it will be to heat loss.

How is heat loss measured?

We measure how effective parts of your building are at insulating against heat-loss by looking at their U-values.

U-values are sometimes called heat transfer coefficients, or thermal transmittances.  They’re measured in Watts per square metre. And they tell you how much energy is lost for every 1°C difference between the two sides of each material used in your building.

In a dilapidated old building with draughty windows and shoddy brickwork; you would see very high U-values, indicating that heat is able to transfer very quickly through the building.

Whereas with a new build with double glazing and plenty of insulation; you would see low U-values, indicating that it takes heat much longer to escape.

How can I reduce heat losses?

Diagram showing low u-values.Heat is lost from your home through your roof, windows, walls, floors and through gaps around windows and doors.

 Air leaks (or draughts) are a double-edged sword. Because as well as heat escaping, cold air can also come in, further increasing your need for more heating.

The good news is that there are lots of simple but effective ways to reduce these heat losses in your home; so that you can be comfortable and minimise your bills and your carbon footprint.

1.    Reduce heat loss by checking your heating controls

A hand operating a smartphone.If your heating system is poorly programmed or has limited to no controls, you’ll be wasting lots of energy.

If you just turn your heating up to full blast in the winter, hoping for the best; this will waste energy because you don’t need the heating to be on full blast 24/7 to be comfortable. And you probably don’t need all your rooms to be at the same temperature at all times.

For example, if you only have one thermostat in your home, which is in a room that is quite cool; it will be telling your boiler to generate more heat, when you’re already warm enough.

If you get too hot, you might then find yourself opening a window – a sort of deliberate heat loss!

Investing in a programmer; room thermostat; and thermostatic radiator valves; could save you £75 per year and 320kg of carbon dioxide, according to the EST.

2.    Reduce heat loss by fitting wall insulation

The biggest source of heat loss from your home (about a third of it) is through your walls, so insulating them is a no-brainer if you want to minimise your heat losses.

The insulation you’ll need will depend on the type of walls you have.

Generally, houses built before 1930 have solid walls, and anything built after this date will have cavity walls.

Cavity walls are the easiest to deal with; because insulating material is simply blown into the cavity between your two walls.

The effect of this is that the material slows the heat from travelling through the walls via conduction. And prevents air moving freely inside the cavity, reducing heat loss by convection.

Solid walls are a bit trickier because there’s no space to fill. So the walls need to be insulated either internally or externally, which can be expensive.

According to the EST, an average semi-detached house can expect to save approximately £225 per year on their energy bills; and reduce their carbon dioxide emissions by 930kg by insulating their walls.

3.    Reduce heat loss by fitting roof (or loft) insulation

Since one quarter of your heat can be lost through your roof through conduction and convection; it’s important to look at your roof insulation in order to minimise these heat losses.

Laying insulation in your loft significantly reduces the amount of heat that can escape through your roof. And the fibres of the insulation can prevent the trapped air from circulating and causing convection currents.

The result is that your lovely warm air is trapped inside the rooms below the insulation; keeping you warmer for longer.

Another bonus is that the insulation will also help to keep out cold air from entering your home.

If you already have roof insulation, it’s worth looking at how thick it is. Just like putting on a big coat, the thicker your insulation is, the better it will perform.

The EST says that where an average semi-detached house goes from having no insulation, to 270mm of insulation, energy bills will be reduced by up to £150 per year. And carbon dioxide emissions will be reduced by up to 610 kg.

4.    Reduce heat loss by adding floor insulation

A dog next to feet in socks.About 15% of all heat loss in your home is through the ground floor. Because the cement slab, which sits underneath the floors of your home; has a high U-value, meaning that it has poor insulation capability.

So, you need to make sure that there is sufficient insulation between the ground and the floor surface.

In new buildings, insulation is installed during the construction. And in older buildings, insulation layers can be laid on existing floor surfaces.

5.    Reduce heat loss by covering bare floorboards

As well as your ground floor being a major source of heat loss; the other floors in your house account for as much as 10% of heat loss if they’re not insulated; according to the National Energy Foundation (NEF).

Carpets and rugs will keep your heat in longer than wooden flooring. And they also have the bonus of keeping your feet nice and warm too.

If you have any cracks or gaps in your flooring, the NEF advises filling these with a silicone-based filler.

6.    Reduce heat loss by investing in double glazing

Heat loss through windows can be reduced by using double or triple glazing. These energy efficient windows have air or a vacuum between two or three panes of glass; which are then sealed in a frame.

Just like how a vacuum flask works for keeping your tea warm, creating a vacuum between the panes of glass, reduces heat loss through conduction and convection.

Where there is a vacuum there will be no conduction or convection because air is a poor conductor, and there is little room for the air to move.

If you’re looking to install double glazing in your home, but are confused by all the choices available, look for the British Federation Rating Council (BFRC) rating.

Similarly, to how boilers are rated for their efficiency, windows are too. Window manufacturers can show the energy efficiency of their products using an energy-rating scale from A++ to E.

Whilst there will be a cost to fitting double glazing, the annual savings on your energy bills for an average semi-detached house, is between £75-80, according to the EST.

7.    Reduce heat loss with your curtains and shutters

Replacing your windows can be expensive, and if this isn’t an option for you right now you can minimise the frustration of your draughty windows in winter months, by installing heavy curtains or shutters.

Although these won’t completely stop air leaks, they will act as a thermal barrier, and will help to reduce heat loss, as well as reducing the amount of cold air coming in.


8.    Reduce heat loss by investing in energy efficient doors

Your doors can also be insulated and draught proofed to prevent heat escaping, and cold air coming in. A properly fitted new external door should include an effective draught-proofing system.

Older doors can be improved by fitting draught-proofing strips around the seals and installing covers on the keyhole and letterbox.

Fitting draught-proofing to the doors and windows will save the typical household around £20 a year.

9.    Reduce heat loss by draught proofing your chimney

If your fireplace is more decorative than functional, it’s probably a source of unnecessary heat loss.

The University of Liverpool calculated that we lose around 4% of household heat out of the chimney.

A chimney balloon is a simple solution to this problem because it is fitted and inflated in your chimney to create a barrier and prevent the transfer of heat.

Draught proofing your chimney when you’re not using it could save you around £15 a year on your energy bills, according to the EST.

10.  Reduce heat loss by getting an insulating jacket for your hot water cylinder

If you have a heating system with a hot water cylinder, check whether it has an insulating jacket. The EST says that just fitting your hot water cylinder with an insulating jacket will save you £20 a year in heating costs and 150kg of carbon dioxide emissions.





11.  Reduce heat loss by investing in a new, energy efficient boiler

A high efficiency installation by The Heating People.How old and inefficient is your boiler? Although not strictly speaking relating to heat loss, the energy efficiency rating of your boiler will still affect your energy bills through lost energy.

Generally older boilers are less efficient than modern ones and cost more to run.

An A-rated boiler has an energy efficiency of 90% or more. The Boiler Plus regulations mean that new combi boilers are at least 92% efficient.

To put this in perspective, an older G-rated boiler has an efficiency of 70% or less which means for every £1 you spend on your heating bill you are wasting 30p on lost energy.

As well as older boilers tending to be less efficient to start with, their efficiency can also deteriorate further with age.

The EST estimates that boilers are responsible for 55% of your household energy bills, so upgrading from a G rated to an A rated boiler could save you up to £200 per year.

Final thoughts…

We hope that these tips will help you to minimise your heat losses and stay warm this winter!

If you want to talk to us about looking at the efficiency of your heating system, contact one of our team at The Heating People, who will be happy to help you.


Useful Links:

The Energy Saving Trust tips on draught proofing.

The Greenage article on draught proofing