Internal wall insulation
Internal Wall Insulation

Internal Wall Insulation

Insulating the internal walls of your rooms will create a thermal barrier between the inside of your home and the outdoors, dramatically reducing heat loss and therefore reducing your energy bills.

Internal wall insulation is suitable for homes constructed from solid walls (as opposed to cavity walls).

You can expect to save around £410* per year on your energy bill (based on a gas-heated semi-detached home) rising to £710* per year (based on a gas-heated detached home).

Save energy & money

Our team has a couple of different methods for internally insulating a space, including rigid wall-mounted insulation boards or a stud wall with insulation behind. During our home visit we’ll assess which one will suit you best and offer our advice. Either way, less heat will escape through your walls after the insulation is installed.

Costs & funding

As an accredited installer, we have access to various pots of funding that can make insulation FREE or very low-cost for you. The funding comes from places such as energy companies, local authorities, and housing associations.

We’ll check what you’re entitled to when you contact us.

Homes built with solid walls are most suited to internal wall insulation, because there is no cavity that can be filled with cavity wall insulation. Therefore, insulation must be applied to the inside or the outside, in this case internal wall insulation is applied to the wall from the inside.

Internal wall insulation can be particularly beneficial when more than one wall of your room is external.

Who needs internal wall insulation?

Home visits to suit you

We’ll ask a few questions over the phone and then book you a FREE home visit at a time to suit you.

Getting internal wall insulation

Get in touch with us, even if you’re unsure of your wall type, and we’ll advise over the phone or by email. Then we’ll book you a FREE home visit for a Home Surveyor to come and take a look at your property and confirm suitability, do a few checks and take some measurements.

The insulation will be fitted shortly after by one of our friendly technician crews.

hot offer fully funded insulation

We aim to get back to you by the next working day

Please enable JavaScript in your browser to complete this form.
Step 1 of 3

Identifying your wall type

Homes built with solid walls are most suited to internal wall insulation, because there is no cavity that can be filled with cavity wall insulation.

Look at the the brick pattern of your property to help you determine whether you have solid walls or cavity walls.

Example of solid wall

Solid wall

The bricks will have an alternating pattern so that some bricks are laid lengthways and some bricks are laid widthways, showing the smaller ends.

Example of cavity wall

Cavity wall

The bricks will have an even pattern with all the bricks laid lengthways.

Internal wall insulation considerations

Installing internal wall insulation can be disruptive, so many people chose to do it as part of a bigger refurbishment, perhaps having a new kitchen, building an extension or decorating a living space. If it’s a whole house project, we would manage it on a room-by-room basis to minimise the upheaval for you.

Although internal wall insulation is a big job, the benefits and cost-savings are big too, reducing energy bills by up to £710* per year (based on a gas-heated detached home).

The alternative to internal wall insulation

There is another option if internal wall insulation isn’t right for you: external wall insulation.

This is a method of insulating solid walls from the outside, rather than the inside.

external wall insulation

evolve installation team

Why choose Evolve?

We’re great at what we do and our team has over 450 years’ experience between us so we know how to do an excellent job. We only use the best materials and all our surveyors and engineers are highly trained and take pride in their work.


Established in 2015


60 members of staff


450 years of combined experience


Over 15,000 homes decarbonised since 2015


A further 80 homes decarbonised every week


3,000 cavity extractions project managed

call us today evolve home energy solutions

We’re open between 9am and 5pm, Monday to Friday. Or drop us a message and we’ll get back to you ASAP.

Internal Wall Insulation FAQs

What is internal wall insulation?

Internal wall insulation is a highly thermally efficient material that is fixed internally to walls, creating a barrier to heat loss through the walls. It is typically used on solid walls where there is no cavity to fill with insulation.

Why should I have internal wall insulation?

Internal wall insulation is great for cold rooms, perhaps caused by there being numerous external walls that heat is escaping through. It is also good for stopping cold draughts.

How long does internal wall insulation take to install?

Typically, three to five days, but it very much depends on the size of the room and any other work that may be going on at the same time.

What prep do I need to do before internal wall insulation is installed?

Your walls need to be clear of things hanging on them such as pictures, TV and ornaments. There also needs to be plenty of clear access to the walls that are being insulated. Your Home Energy Surveyor will discuss this with you at the home visit.

How much money can internal wall insulation save me on my heating bills?

The Energy Saving Trust estimates that up to £710 per year* on heating bills can be saved by a detached home.

* Estimates taken from the Energy Saving Trust, August 2023 (