How to insulate a home to keep heat from escaping this winter

A few fixes can make all the difference in helping to keep your home toasty warm and your energy bills down

Loft bathroom with wooden flooring and ceiling panelling
(Image credit: Future PLC/Simon Whitmore)

As the colder months take hold and the energy bills start to rise, we start to think more than ever before about how to keep our spaces warm. Knowing how to insulate a home can make all the difference, saving you chills and pennies.

Working out how to keep your house warm in winter can seem tricky, so we've broken down how to keep things as cosy and as snug as can be be - whatever the weather.

'A badly uninsulated home will feel colder quicker and retain less heat, resulting in the boiler working harder and costing more in energy bills,' says Jenny Turner, Property Manager, Insulation Express. 'Many older homes in the UK often have insulation that is poorly installed or is under the latest recommended regulation amount, making the property less energy efficient.'

How to insulate a home

When planning to insulate a home, first be aware of where you're losing heat the most. 'You can lose around a third (35%) of your home’s heat through your walls and it’s estimated another quarter (25%) is lost through your attic, so, these areas are where you’ll lose the most heat in your home,' says Joshua Hammonds, Marketing Manager, Hammonds Furniture.

'However, windows are also a key area of heat loss, with about 18% of a home’s heat loss occurring heres. It is estimated that you also lose another 10% of your home’s heat through your floors.'

With this in mind you can make sure you're protecting the areas losing the most heat in your home.

1. Check if your home is insulated properly

Blue living room with blinds and curtains on wall behind sofa

(Image credit: Future PLC)

When working out how you're going to insulate a home, a good starting point is finding out where your house currently stands with its insulation. 

'There are some tell-tale signs that your home’s insulation could be improved upon,' advises Stephen Hankinson, Managing Director, Electric Radiators Direct. 'If you feel lots of cold draughts and breezes in your home, this is a sign that your home needs better draught proofing. If your house immediately gets colder after you’d turned the heating off, then this could indicate that heat is escaping too quickly.'

'Insulation may be patchier in some areas of your home than others. If certain rooms are colder, this could help you work out what type of insulation you should invest in. A draughty top floor for example, could indicate you’d benefit from roof insulation. Cold outward facing rooms may benefit from wall insulation.'

Additionally, if you're already trying to work out how to stop dampness coming through walls, note that one of the causes of the damp can be linked to poor insulation. 

2. Insulate your floors

Country style kitchen with wooden floors and blue cabinetry

(Image credit: Future PLC/Rachael Smith)

'An uninsulated floor is relatively easy to spot, as you’ll be able to feel a subtle draft when up close allowing cold air in and for warm air to escape, which in the cooler months will become increasingly obvious,' explains Caroline Hansson, Head of Design, Luxury Flooring & Furnishings. And since heat rises, floor insulation can make a big difference in your home.

'If you’re looking for a floor that in itself is a great insulator of heat, an engineered floor is perfect. Engineered wood is made up from layers of either plywood or MDF and finished off with a surface layer of solid wood, which retains the heat better than laminate or vinyl flooring.'

'Particularly if you have older solid wood floors, you may find that they have shifted and there are some gaps in between planks,' continues Caroline, 'I’d advise filling these in where possible, as they can result in drafts and affect the efficiency of your heating.' To insulate a home here, you can fill these with wood filler or wood glue, available on Amazon, relatively easily.

3. Cover up your windows

Neutral living room with rug, fireplace, coffee table, sofa and blind on window

(Image credit: Future PLC/Simon Whitmore)

'One of the most affordable and easiest ways to insulate your home is to install thermal blinds,' explains Sophie Moore, Content Editor, Unbeatable Blinds. 'Thermal blinds use a special lining or thermal technology to prevent heat loss, keeping the cold out and the heat in, especially in the winter months.'

'Cellular or Honeycomb blinds are the best option on the market for insulating your home,' continues Sophie. 'These innovative blinds feature honeycomb shaped blind pockets that trap air, insulating your room, draught proofing, and reducing your energy costs. If you want to take it a step further, you can pair your blinds with some thermal curtains for further heat retention.'

As well as window dressings, there are other ways to insulate a home and stop losing heat through windows. 'Draught excluders along windowsills can provide a barrier against draughts coming from windows,' suggests Jenny from Insulation Express. Additionally, resealing the edges of window frames with self-adhesive foam tape, from £7.99, Amazon, can also stop cold air from entering the room'

4. Protect your doorways

Entryway area with draught blocker in front of door

(Image credit: Future PLC/David Brittain)

Fit self-adhesive foam strips around windows, or metal or plastic strips with brushes attached to insulate a home. External doors can be a major source of draughts, so cover your keyhole; fit a letterbox flap or brush and use a brush draught excluder at the bottom. Gaps at the sides can be dealt with in the same way as windows to stop draughts from doors.

'Draught excluders can also help trap heat in your home by blocking any draughts,' adds Joshua from Hammonds. 'You should close doors to stop most of the air following from room to room, and then invest in a draught excluder to sit at the bottom of the door and block any gaps.'

5. Insulate your loft

Loft bathroom with wooden flooring and ceiling panelling

(Image credit: Future PLC/Alistair Nicholls)

'Good loft insulation is essential for those looking to save money on their energy bills,' advises Jenny from Insulation Express. 'Depending on the material, loft insulation should last between 80 - 100 years, so it is worth the initial investment. If you are using glass wool, sheep’s wool or loose fill, then the depth should be 300mm, and rock wool should be 250 millimetres.'

'Spray foam increases in volume, so you don’t have to use as much to get the same effect as other materials. Cellulose should have a depth of 220 millimetres.'

'There are two types of insulation for lofts - warm loft insulation is installed under a pitched roof beneath tiles. Space should be left under the roof tiles free from insulation material to allow for adequate ventilation so that you don’t get condensation coming through the tiles. This kind of insulation is ideal for when the loft is used as a room or for storage, though it does come with a higher cost.'

'Cold loft insulation is the most popular method and involves material being placed over the top of and in between all of the wooden joists above the ceiling of the top floor of your home.'

6. Fill cavity walls

Neutral living room with wooden walls and stove

(Image credit: Future PLC)

If your home was built between 1920 and 1990 it probably has cavity walls and knowing if you have this or not will affect how you insulate a home.

'Wall insulation is highly advantageous to keep costs low on your energy bills. Cavity wall insulation may already be in place in your property, and you can usually check the brick pattern to ascertain this,' advises Jenny from Insulation Express.

'If you have cavity walls and require polyurethane foam insulation, this will need to be installed by a professional who will drill holes into the external walls and inject the material before sealing with cement. Solid wall insulation however can be done by fitting rigid insulation boards to either the internal or external walls before covering with plaster or cladding.'

6. Wrap cylinders and pipes

Boiler in white kitchen cabinet

(Image credit: Future PLC)

Hot water pipes exposed? You’re wasting money and hot water by not giving them ‘jackets’ – foam tubes that cover the exposed pipes between your hot water cylinder and boiler. They're an easy and budget-friendly way to help, with foam pipe available from £1.38 per m at B&Q.

'Make sure that you lay ample insulation around any heating pipes,' says Caroline from Luxury Flooring & Furnishings. 'This way you’ll keep them at their optimal temperature and they shouldn’t lose any heat.' Just make sure to find out your pipe diameter before buying. 

7. Insulate behind radiators

Hallway with radiator under window

(Image credit: Future PLC)

Popping a shiny foil panel behind your radiators may sounds like a - ahem - tinfoil hat theory, but it can work. If you don't have any underfloor heating, then making your radiators as efficient as possible is key.

'Traditional central heating radiators work at only about 50-70% efficiency,' points out Stephen from Electric Radiators Direct. 'Placing silver foil behind them will reflect heat back into a room rather than letting it escape through the walls.' Rather than using flimsy and fiddly tinfoil, use purpose made radiator foil, from £9.50, Amazon.

How do you check if your home is insulated properly?

'Start by checking for gaps in insulation,' suggests Jenny from Insulation Express. 'For how to insulate a loft, know that the insulation should reach every corner of the loft with no gaps or shallow pockets that could let heat escape, vastly reducing your homes heating efficiency.'

To check your loft insulation, Jenny advises following these steps:

  • Measure the depth of the existing insulation using a tape measure and make a note.
  • Next, measure the spacing between the joists. Begin at the mid-point of one joist and measure to the mid-point of the next one along. Usually, the distance will either be 400 or 600mm. This will then show you what the width of the insulation you may need is.
  • The ideal thickness depends on the type of insulation that you are using. For loft insulation, the recommended thickness for glass wool insulation is 300 millimetres on new builds, 250 millimetres for rock wool, and 220 millimetres for cellulose. 

'Next, feel for cold spots, damp and draughts,' continues Jenny. 'Use your hand to feel along a wall to see if it is damp, and any visible signs of mould and damp can be a clear sign of poor insulation in addition to a lack of ventilation.'

'After this, refer to your property’s Energy Performance Certificate (EPC). If your property scores on the lower end of the scale, you will know that there are improvements to be made in terms of insulation and energy efficiency.'

'Another way to find cold spots is to invest in a thermal imaging camera to work out where to insulate a home. Using the camera on the external areas of the property with the heating on inside and on a night time for easier visibility, this will visually highlight areas where the surface temperature changes from warm to cold, and will identify weaknesses in current insulation.'

Thea Babington-Stitt
Managing Editor

Thea Babington-Stitt is the Managing Editor for Ideal Home. Thea has been working across some of the UK’s leading interiors titles for around 10 years.

She started working on these magazines and websites after graduating from City University London with a Masters in Magazine Journalism. Before moving to Ideal Home, Thea was News and Features Editor at Homes & Gardens, LivingEtc and Country Homes & Interiors.