Insulation is one of the most effective ways to save money and energy in your home

A well-insulated home:

  • Stays warmer for longer, stopping heat from escaping from your walls or loft space
  • Keeps the heat in during the winter and the warmth out during the summer
  • Takes less time to warm up
  • Improves the external appearance of your home if you have external wall insulation
  • Can help save you up to £490 a year* on your energy bills

The main routes for heat to escape from your home are through your walls and your roof, so these are the main areas to make changes. There are also many little measures that you can take to help keep the heat in, click here to read our energy tips.

Loft insulation

Heat rises, and in an uninsulated home, a quarter of heat is lost through the roof. Insulating your loft, attic or flat roof is a simple and effective way to reduce heat loss and reduce your heating bills.

Click here to find out how much you could save. Loft insulation is effective for at least 42 years and it should pay for itself many times over.

What is loft insulation?

Loft insulation is a thick material that’s rolled onto the floor of your loft. It acts like a blanket, helping to stop heat escaping through the roof. The most common form of loft insulation in UK homes is made from glass fibre, however there are many greener alternatives such as sheep's wool. Click here for further information.

If your house is over fifteen years old it is highly likely that your insulation will need topping up as building regulations are continually changing, requiring homeowners to have thicker and thicker layers as the years go on. The current recommended depth is 275mm (just under a foot).

What are the benefits of loft insulation?

Heat rises so loft insulation acts like a blanket, trapping the heat in your home. This helps to reduce heating costs, keep you warm and help the environment - a home without loft insulation could waste as much as £220 a year extra on heating bills and emits around 1.5 tonnes of CO2.

Are there currently any grants towards loft insulation?

See our Grants Available page for more information.

Wall insulation

About a third of all the heat lost in an uninsulated home escapes through the walls. Heat will always flow from a warm area to a cold one. In winter, the colder it is outside, the faster heat from your home will escape into the surrounding air.

There are two main types of wall insulation depending upon what type of walls your home has; insulation that goes on the outside of solid walled buildings and insulation that goes inside walls that have cavities. If your house was built after the 1920s, it is likely to have cavity walls. Older houses are more likely to have solid walls.

External wall insulation

Watch our video about external wall insulation: find out how it renews the look of a home, keeps you warmer and stops you wasting money and heat through your walls. Hear from Plymouth residents; see what their houses looked like before and after.

What is External Wall Insulation?

Its ever such a simple idea, same principal as a tea cosy; like a blanket for your home, wrapping it from top to bottom. External wall insulation can be applied to any wall but its main application is for houses that are not suitable for cavity wall insulation. Usually, this a house with solid brick or solid concrete walls.

Before... ...and after! (it's the same house, promise!)

How does it work?

Solid walls (generally made of stone or brick) let twice as much heat escape as cavity walls do. If your home was built before 1919, its external walls are probably solid rather than cavity walls. Cavity walls are made of two layers with a small gap or ‘cavity’ between them. Solid walls have no gap, so they let more heat through.

External wall insulation involves fixing a layer of insulation material (either a polystyrene or mineral wool board) to the existing wall, then covering it with a special type of render (plasterwork) or cladding. The finish can be smooth, textured, painted, tiled, panelled, pebble-dashed, or finished with brick slips.

By wrapping the whole house in insulation the heat is kept where you need it: inside!

What are the benefits?

External wall insulation can:

  • Help keep your house warmer and more comfortable
  • Reduce your energy use for heating and bills, an average 3 bed semi-detached property could save up to £270^ a year
  • Reduce your property’s carbon footprint
  • Renew and improve the appearance of your property
  • Improve weatherproofing and sound resistance
  • Reduce condensation on internal walls and can help prevent damp (but will not solve rising or penetration damp)
  • Increase the life of your walls by protecting the brickwork
  • Give your home a maintenance free finish - most external wall insulation systems are guaranteed for at least 25 years meaning you can fit and forget and don't have the worry of repainting
  • Improve the energy rating of your property - recent government research suggests that it could improve the band from G to E or D to B, increasing your property value by up
  • What will it look like?

    You might need planning permission as it could change the appearance of the building, anyone giving you a quote will advise you if this is necessary or you can check with your local planning authority. There are a wide range of colours and finishes that can be applied, you can discuss these with your installer. They can replicate the existing finish to preserve the original appearance if you prefer.

    Once installed, the insulation will obviously stick out further than your wall. Ideally your next door neighbours will get it done as well! If not, the installers blend it as much as possible.

    You may also find that certain decorative features are lost unless you pay extra to replace them. Vents are obviously replaced and so are the window sills, please note that these will be PVC, unless you pay extra for a different type. Canopies, downlights, pipes, satellite dishes and hanging baskets will temporarily be removed and replaced afterwards (satellite dishes can be temporarily fixed to scaffolding during installation). The insulation will only going down as far as the damp course.

    Click here to see a gallery of detailed images of external wall insulation.

    Are there currently any grants towards external wall insulation?

    See our Grants Available page for more information.

    Our 2014-2016 external wall insulation scheme

    We worked in partnership with Plymouth City Council, British Gas and local installers to help private properties in Plymouth receive grants towards installing external solid wall insulation. Between 2014 and 2016, 700 households in Plymouth received grants towards external wall insulation.

    Testimonials from happy residents

    One local resident who’s benefited from solid external wall insulation is Teresa. Her daughter has long-term health issues and every year she suffers from cold-related illnesses, including poor circulation. She had external wall insulation added to her Whitleigh home in February 2015 and is full of praise:

    “For the first time in years my daughter and I haven’t had colds, we’ve been able to turn the heating down and switch off our small heaters. Before we got the insulation I was constantly painting over black mould and now we don’t have any damp or mould issues, even when it rains! Our home is quieter and we’ve noticed a good improvement on our bills; rather than dreading the winter now I’m excited about really feeling the benefits. It’s quite remarkable and I can’t thank everyone enough; it really is life-saving.”

    'We had timber cladding with not very good insulation behind it, this was all replaced with this new render insulation and it makes our house look so much better' N. Daley

    'Since I have had the External Wall Insulation done I have noticed that every room is a lot warmer, I can definitely feel the difference' S. Shaw

    'The whole process went well and I'm really happy with the finished result, it should make the winters a little warmer!! I have also noticed it is a lot quieter, which is an added bonus! So very happy :)' Plymouth resident

    Cavity wall insulation

    A cavity wall is made up of two walls with a gap in between, known as the cavity; the outer leaf is usually made of brick, and the inner layer of brick or concrete block.

    What is cavity wall insulation?

    Cavity wall insulation can be made from three types of material: mineral wool, beads or granules, or foamed insulants.

    To insulate your cavity walls, the installer drills small holes around 22mm in size at intervals of around 1m in the outside wall of your home. The installer then blows insulation into the cavity using special equipment. Once all the insulation is in, the installer fills the holes in the brickwork so you'll barely notice them.

    Filling cavity walls is not a job you can do yourself, you will need to employ a registered installer. A professional can do the job in around two hours for an average house with easily accessible walls.

    What are the benefits of cavity wall insulation?

    If your home was built after 1920, the chances are that its external walls are made of two layers with a gap or cavity in between.

  • Cavity wall insulation fills that gap, keeping the warmth in to save energy
  • It can also help reduce condensation inside the house if this is a problem stemming from your external walls
  • If you have a typical house with cavity walls, you could save up to £160 per year in heating bills just from insulating the walls.
  • Are there currently any grants towards cavity wall insulation?

    See our Grants Available page for more information.

    *Example based on a detached home with gas heating. Source:, September 2013. Actual savings depend on individual circumstances.