A Guide to Internal Solid Wall Insulation

If your home is built from solid walls, internal solid wall insulation will save on your energy usage – particularly if external insulation isn’t possible.

internal solid wall insulation

If you live in a terraced house, flat or any other type of home where it isn’t possible to get external wall insulation fitted, you may want to consider the benefits that internal solid wall insulation could bring. Many newer buildings are being built with cavity walls and as such you’ll need cavity wall insulation and/or external wall insulation if you can budget that as well. It’s mainly older buildings which are built with solid walls, but it’s not unknown for modern buildings to use them as well depending on what home style is being gone for.

Internal solid wall insulation is quickly becoming a popular choice for people wanting to better insulate solid-walled homes. As it’s intended for indoors you can use it in any type of property. There are about 10 million properties in the UK which are built with solid walls, which is roughly 40% of an estimated 25 million UK homes. Solid walls unfortunately let twice as much heat escape as cavity walls do, so it’s important to consider investing in some internal solid wall insulation.

Installing the appropriate amount of insulation will help preserve older buildings and maintain more recent ones. It’ll also cut your energy bills down and help you to limit how much CO² your house is projecting into the atmosphere. You could end up saving around £460 a year by installing internal solid wall insulation, and 1.8 tonnes of CO². Anywhere near those figures would be a great saving for both you and the environment.

It may cost an initial £5,500 – £8,500 to install internal solid wall insulation around the home, but you’d make that back in less than 20 years at the very most, and you’d have a very green conscience. Not only that, but this is far cheaper than what it costs to install external insulation, which can be anything from £9,400 – £13,000 on average (www.energysavingtrust.org.uk). And in no more than three years, the amount of energy you save will pay back the amount of energy it took to produce the insulation in the first place (this is called the ‘embodied energy’). If it’s a green home you’re looking for, internal solid wall insulation will provide it.

What exactly does internal solid wall insulation entail?

It’s most commonly done by attaching insulation boards across the outside-facing walls you need to insulate.  The insulation is then normally covered with plasterboard to give a smooth finish so that it keeps continuity with the rest of your interior walls. And it’s as simple as that. It can often be a very quick and simple process, and it doesn’t need to take things like weatherproofing into consideration as its primary purpose is to insulate.

But there are several things you’ll need to think about before getting some fitted. The process is simple, but the planning needs time and it’ll be handy to know exactly what you’re going for.

Plumbing, wires, pipes

You need to check every wall for penetration services which run along or come through from outside. You need to make sure that by installing internal solid wall insulation you’re not completely blocking access to these things, or allowing them to be dangerously exposed or at risk from being on the cold side of the insulation.

You should also consider radiators and power outlets which will need to be remounted on the new plasterboard surface, as well as the removal of skirting boards and door frames.

plug hanging out 300x225 A Guide to Internal Solid Wall Insulation

Traditional British damp

While internal solid wall insulation isn’t built to withstand gale-force winds and torrential downpours, it can deal with something that homes in the UK know all too well: damp. Just behind the plasterboard will be a membrane which will protect against damp and condensation. Condensation can accrue when warm air from inside enters the wall and mixes with the cold from outside. And in the UK dampness can seemingly occur anywhere.

damp dangerous 300x225 A Guide to Internal Solid Wall Insulation

There are several different insulation materials however which will limit this as much as is physically possible. Head over to Yougen for an article which explains the science behind the different types and the methods by which they protect your home from unwanted moisture.

A reduction in floor space

You’ll need to carefully consider your internal solid wall insulation so that you have an adequate amount of it to insulate your home without it intrusively reducing a room’s floor space. Ideally you shouldn’t use any more than 10cm of insulation or else smaller rooms may become uncomfortably poky. This measurement doesn’t include the plasterboard, fixtures or adhesives, so you must allow for an additional 3cm regardless how much insulation you’re fitting.

Thick insulation may mean your home is exceptionally well insulated, but it may mean that you don’t actually save any money or energy. Make sure you accurately calculate how much you need and don’t use a single millimetre more.

Images: Yorkshire Housing, Angie Ell, Wise Property Care

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