Homeowners looking to improve the energy efficiency of their homes or looking to reduce energy bills may be interested in external wall insulation. A great solution to prevent heat loss and an alternative to cavity wall insulation or internal wall insulation, external wall insulation is popular for a good reason.
But if you've not heard of it before, or you're not sure what the difference between all the insulation systems is, here's what you need to know:
External wall insulation is, essentially, a layer of insulation fixed to the outside of an existing wall. The whole thing is usually between 50mm to 130mm deep and involves an insulation board that will slow the loss of heat attached to the external wall. This is attached with external fittings and mechanical fixings to hold it in place. There is then a middle section of mesh between two thin layers of render to provide strength and rigidity, and then a final coating of cladding or render is applied to give the wall a smooth appearance.
External wall insulation is a common method of insulating solid walls. It is an alternative to cavity wall insulation, as this is not possible when a property has solid walls. As well as providing a great solution in terms of insulation, external wall insulation is also topped with silicone render that allows you to choose the colour and finish when installing external wall insulation.
Just like any other kind of thermal insulation, external wall insulation works by restricting conduction, convection, and radiation of heat through the home to prevent heat loss.
There are a number of reasons to invest in external solid wall insulation. It is a great choice for properties with solid walls. Some of the benefits are:
By providing an additional layer of insulation material external wall insulation prevents heat from escaping the home. This allows you to use your heating less, thus reducing heating bills. Not only will the energy bills be cheaper, but your home will be more energy efficient and the increased thermal performance will improve your carbon footprint, too.
The exact amount of money you will save on your energy bills once external solid wall insulation is installed will depend on a number of factors, however, generally speaking, you can expect to save a decent amount.
On average, a mid-terraced home can save around £160 per year. A semi-detached home may be able to save as much as £255 per year, and a detached home could save as much as £425 per year!
Discover more: How Much Does External Wall Insulation Cost
A lot of homes, especially older properties, suffer from draughts. This is especially true if there is no kind of insulation to help prevent them. These draughts can make the home feel cold and can cause you to turn the heating on unnecessarily, boosting the heating costs.
With the use of external wall insulation, you can reduce the chance of draughts and increase the cosiness and comfort in your home by creating a better thermal barrier between you and the outside world.
Since external wall insulation involves an external installation process it doesn't get in the way of your life as much as internal wall insulation might. You will need to provide access to the property, water, electricity, and probably a bathroom, but the inside of your home will not be being worked on. This means you can install external wall insulation while you continue your day-to-day business without worrying about getting interrupted or getting in the way. The only impact might be some scaffolding and the odd labourer popping into the property.
Unlike internal solid wall insulation, external wall insulation does not cut into the space on the inside of the home. This makes it an ideal choice for people with smaller homes or who don't want to lose any floor space in their homes.
Just like internal wall insulation and cavity wall insulation, external wall insulation provides a layer of soundproofing to the property. This means that you are less likely to be interrupted by the noise outside, and you are unlikely to be heard from outside, too!
So long as external wall insulation is installed correctly it will help to reduce condensation by stopping the internal walls from being cold. In addition to the insulation itself, the silicone render will prevent moisture from being absorbed into the insulation material and then the wall, further protecting your home.
When installing solid wall insulation, the board that is placed up against the external walls works to protect stone walls and any brick wall from weather, staining, and damage. This can increase the lifespan of the outer wall.
Explore in-depth: How Long Does External Wall Insulation Last
There are of course downsides to external wall insulation, just like with any kind of home improvement project. These do not outweigh the benefits, though, and can be handled through discussion with experts like the MisterRender team before you begin installation.
Examples of the disadvantages include:
Depending on the property and the end goal of the external insulation, you might find that increasing the size and changing the aesthetic of your property involves planning permission. It is always important to check with your local authority to be sure, as they can fine you if you act without the proper permissions!
Gain insights: Does External Wall Insulation Require Planning Permission
Covering your whole house in layers of insulation and then adding a render to the insulation layer is not a quick process. The materials themselves are costly, and then you add on labour costs. However, this is the case for most insulation installations.
The best way to look at installing solid wall insulation is as an investment. It may be costly to start with, with typical installation costs sitting at around £4,000-£6,000 for a mid-terraced house, £8,000-£10,000 for a semi-detached house and £12,000-£14,000 for a detached house, but it will save you money.
The use of insulation boards can cause 'cold bridges' around windows, doors, and eaves if not installed correctly. Left alone, these weak spots compromise the external wall insulation layer and allow heat to escape. Ultimately these then render the process pointless. As such, they must be addressed when the insulating material is installed.
