Many people believe that heat only ever flows upwards – this is actually not the case! Heat is capable of flowing in any direction – upwards, sideways, and downwards, although generally, it flows from higher temperature areas to those places where temperatures are lower. This explains why warmth from inside a heated home, whether fuelled by heating oil, LPG, mains gas, or any other energy source, will flow to the cold outdoors. And any part of your home that is not properly insulated will result in heat loss, leading to higher fuel bills – something we all want to avoid, and especially important in these current times with the cost of living crisis. And of course, a cold house can also be bad for your health!
There are several common myths surrounding the topic of heat loss and energy saving in the home. For instance, many people believe that cranking up the thermostat will warm up your home quicker which is simply not true - it only wastes energy. So here we’re going to look at the 4 main sources of heat loss in the home, and what you can do to address them, as well as some other common myths.
The four main causes of heat loss
Your walls:
The Energy Savings Trust has been encouraging homeowners to insulate their homes for many years. And for good reason! According to the Trust, about a third of all heat lost in an uninsulated home escapes through the walls.
Our walls are often the largest surface area exposed to the outside of our properties and without insulation, a significant amount of heat escapes through our walls in the winter months and allows cold air to seep in, creating drafts and unevenly heated rooms. This can cause condensation to form as the indoor warm air meets the cold air from outside, leading to damp and the growth of mould, and potential damage to paint and wallpaper.
If your property was built after the 1920’s. it is likely to have cavity walls, whereas older properties are more likely to have solid walls with no cavity.
If you have cavity walls that have not previously been insulated, by installing cavity wall insulation the Energy Savings Trust say you should be able to make back the cost of installation in five years or less due the savings you’ll make on your energy bills. The Trust recommends you choose an installer that is a member of National Insulation Association (NIA), Cavity Insulation Guarantee Agency (CIGA), or British Board of Agrément (BBA). You should also check the insulation is covered by an appropriate 25-year guarantee.
Your installer will drill small holes at intervals around the outside wall of your home then blow insulation into the wall cavity using specialist equipment, filling the holes once done.
If you have solid walls, these can still be insulated either from the inside or from outside by applying insulation boards to provide a continuous thermal barrier – although for external insulation you should check local building regulations for any rules or restrictions.
Your roof and loft space:
Again roof and loft insulation reduces heat loss and helps to lower fuel bills. According to The Energy Savings Trust, a quarter of heat is lost through the roof of an uninsulated home.
Obviously if you live in a flat with neighbours upstairs, you will not lose any heat through your ceiling. If your loft is easily accessible, it should be easy to insulate and possible to do yourself with rolls of mineral wool insulation which can be purchased from your local DIY store. However, you do need to bear in mind condensation with will probably need increasing to avoid damp problems.
There are different materials that can be used, such as sheep wool, spray foam, and reflective foil insulation, which is often combined with other insulation materials. Whatever materials you choose must be fire-resistant and comply with safety standards, and we would always advise you to follow local building regulations for recommended thickness.
Windows and doors:
Contrary to popular belief, windows and doors actually account for the least amount of heat loss in the home. It is true that draughts are more noticeable when they are coming through windows and doors. However, these points of entry actually account for very little of the surface area of your home’s exterior. As most of this surface is taken up by the walls and the roof, it is here that most of the heat is lost.
Gaps around window and door frames allow cold air to get in and warm air to escape, and even your letterbox can allow significant heat to escape. The good news is that draught-proofing is inexpensive, and yet extremely efficient and can make a real difference. Weather-stripping tape is cheap to buy from your local DIY and when applied, creates a seal to prevent draughts, and caulking any gaps and hanging thick curtains can also have a big effect. A letterbox flap will help prevent heat loss, and a home-made draught excluder stuffed with spare material or old clothes will block any gaps at the bottom of your doors.
Floors:
Losing heat through the floor of your home is a common problem, with the amount of heat lost being dependent on the age and the construction of your home – older homes with uninsulated solid floors are particularly vulnerable. Also, gaps and cracks between floorboards and around skirting boards will let warm air escape and cold air creep in. Adding a layer of cost-effective rigid foam insulation or underlay between the floor and carpet can make a big difference and deliver long-term energy savings, and adding thick carpets, rugs, and draught excluders can further prevent draughts and improve your home's comfort, although it’s important to take care not to block air bricks or vents when insulating.
Whilst some forms of insulation need a professional and can be expensive, and older homes may need more work than newer ones, as we have seen, there are also steps you can take yourself to make your home warm and cosy. It’s also worth checking to see if there are any government incentives for which you may be eligible under The Great British Insulation Scheme.
Let's do some myth-busting!
We all want to do what we can to keep our energy usage and costs down, so here we look at some of the most common myths:
It's cheaper to leave the heating on all day
Although this is not conclusive, it's thought that leaving the heating on all day leads to greater heat loss - and bigger bills. Of course, the amount of heat lost depends on how well insulated your property is. Modern heating systems have programmable thermostats so heating can be set to come on before you get up in the morning, or before you come home from work so you get back to a lovely, warm and cosy home. And with a smart thermostat, you can adjust your heating wherever you are using your smartphone.
A bigger boiler means better efficiency
It's true to say that bigger isn't always better - your boiler should be the correct size for your home and your family's requirements for heating and hot water. An oversized boiler can short-cycle, preventing it from operating efficiently, which would waste energy, lead to higher fuel costs and potentially lead to wear and tear. The best way to keep your boiler running at maximum efficiency, whether it's a domestic heating oil boiler, a mains gas boiler, an LPG boiler or any other type, is to have it serviced annually by a qualified engineer.
Leaving lights on uses less energy than switching them on and off
It's often thought that when you turn on lights they need an extra boost of energy to power up. Modern LED bulbs use very little power so they don't require that extra energy to power up. Lights consume energy whenever they're on, so turning them off stops energy consumption and saves money.
Unplugging appliances doesn't save money
There's a common misconception that devices left in standby mode use very little power, but unplugging appliances could save you more money than you think. The power they use on standby is known as 'vampire power' and unplugging devices like your phone charger or games consoles when not in use could save as much as £45 or more over a year according to The Energy Savings Trust.
Painting radiators black improves heat output
The colour of your radiators won't make any difference to the heat output. However, adding reflective panels behind your radiators does. They can be purchased from your local DIY or you can use strong kitchen foil, both of which will reflect the heat into your room and prevent it escaping through your walls.
Insulating your home and reducing heat loss has significant benefits. Well-insulated homes always use less fuel as insulation helps to retain heat so your boiler doesn’t have to work as hard – resulting in lower energy consumption, and savings on fuel costs, whether you use heating oil, mains gas, LPG, electric, or any other energy source. Plus there’s the comfort factor too, as good insulation helps to create a more consistent and less draughty indoor temperature throughout the year, reducing draughts and the need for excessive heating, and eliminating cold spots.
Plus sing less fuel means fewer carbon emissions, helping to create a more sustainable home too, so insulating really is a win-win – cutting both costs and your environmental impact and carbon footprint.