Room in Roof Insulation

Find the right option and trusted room in roof insulation installers with Insulation Advisor.

Save £100's on Your Energy Bills
Make your home more energy efficient
Reduce your carbon footprint
Free no obligation quote
0% VAT Payable on Home Insulation
Improve indoor comfort & air quality

How it works

Enter Your Details

Provide a few basic details to get started

Book Your Free Survey

We visit your home to assess suitability for solar

No Obligation Quote

We provide your highly competitive free quote

Your insulation is installed

Start enjoying the savings with your new insulation

While it’s easy to find tips on insulating an unconverted loft, when you have specific plans for a loft as an extra living space, such as a bedroom, or even an office space, what is involved will usually be more complex.

This process of insulating a converted loft space is called room in roof insulation. Since the Energy Saving Trust estimates that around 25% of an uninsulated home’s heat is lost through the roof, there are many benefits to insulating a roof and loft space in general.

Here’s a comprehensive guide to this type of insulation, including costs, lifespan, pros and cons, and more.

room in roof insulation

What is Room in Roof Insulation?

Room in roof insulation is used to insulate a loft that’s been converted into a usable room, other than being used just for storage. This type of insulation replaces the loft insulation normally seen in an unconverted space.

Installing adequate insulation helps keep your roof space warm and liveable, reducing the amount of money that needs to be spent on energy bills. Properly installed insulation can also prevent issues with damp and moisture.

There are several ways a room in the loft space can lose heat, including properties that contain any of a number of features, including sloped ceilings, stud walls or party walls, gable walls, a dormer window, a fixed staircase or a flat roof. If you don’t insulate the roof properly, heat will escape, leaving the room cooler and potentially prone to condensation issues.

Room in roof insulation prevents the heat from being lost by creating a thermal barrier. The best way to maximise energy efficiency gains is to insulate each element of the room appropriately.

what is room in roof insulation

How Do I Know If My Loft Is Already Insulated?

If you’re moving into a property and want to know whether or not it’s already insulated, there should be information in either the paperwork you received about the house or the survey.

Otherwise, you can check for insulation wool between joists. If you’re still unsure whether your loft is already insulated, hire a professional to carry out a quick survey of the space and let you know.

The Pros and Cons of Room in Roof Insulation


If you choose to insulate your loft using standard traditional techniques, you won’t realistically be able to use the space as a bedroom or office. By installing this insulation, you can transform your space to create a new room in your house to use however you like.

Whether you have a baby on the way or simply want a new space to work remotely, transforming your loft can reap rewards. It can also help to increase your home’s value to have another, properly insulated room in your home.

Every type of insulation is excellent for reducing the annual costs of your energy. By keeping your home warmer without having to overly use central heating or electric heaters, you can expect to save hundreds of pounds on your energy bills every year.
As well as saving money on your energy bills, insulating a loft space promises a return on investment in terms of your property’s value. Prospective buyers are always looking for ways they can reduce their spending on a new home, and having the insulation already installed is certainly more preferable to an uninsulated home.
A well-insulated home means better energy efficiency. The less you need to use central heating or other methods to heat the home, the better your carbon footprint.


Unlike insulating a loft when you don’t need to use the space, converting your loft space into a warm, liveable room is a bigger, more expensive, and more time-consuming project. Unless you need this specific insulation, opt for regular loft insulation to save time and money and experience minimal disruption.

You’ll need to convert your loft into a room using a conversion before insulation work can begin. There are other reasons why your loft may not be suitable for room in roof insulation, including damp or the style of your roof. If your roof is too low or the loft is hard to access, it won’t be suitable for use as a room.

How Does Room in Roof Insulation Work?

When a roof space is converted into a room, it requires a type of insulation that fits into the gaps between the joists or the rafters underneath the roof. If you try to convert a room without installing insulation, the room will be susceptible to significant fluctuations in temperature in the summer and winter months. Not to mention, the rest of the house will suffer from poor thermal efficiency if you fail to properly insulate your loft.

The most common method involves fitting insulation boarding in between the rafters underneath the existing plasterboard walls. This type of insulation traps heat within your home, creating a blanket effect.

With room in roof insulation, you can keep your loft warm in the winter and cool in the summer, allowing you to enjoy a much more consistent temperature all year round. This is because the insulation’s heat-trapping properties retain the heat indoors in winter, and stop the heat from entering during the hotter summer months.

This type of insulation also requires you to install a vapour barrier. While some varieties of rigid foam insulation don’t need protection and blanket insulation already comes with vapour-retardant facing, other types will need a barrier.

You can install a thin barrier of polythene on the underside of the insulation to prevent moisture from compromising your material. Always use unfaced insulation (i.e. lacking a vapour retarding surface and therefore non-combustible) near chimneys or when you’re adding new insulation on top of existing insulation.

The Main Types of Room in Roof Insulation

Traditionally, you’ll insulate the vertical wall sections of the attic room with either insulation boards or fibreglass wool. You’ll also place boards or fibreglass wool between the ceiling rafters. 

Insulation boards tend to be cut to size to fit your space. These boards are ideal for moisture control, so if your loft is prone to condensation, insulation boards ate the best option. You can even cover them with plasterboard for a more attractive finish. 

Cold vs Warm Lofts

There are differences in how you insulate your roof depending on whether you plan to use your loft as a room, or simply a storage space. The key difference is the positioning of the insulation.

To insulate a loft used for storage, you’d need to insulate directly on top of the joists to the ceiling below. For room in roof insulation, you need to layer the insulation just underneath the roof. This allows the heat from the rooms below to travel into the converted attic, so the attic room also benefits from extra warmth.

Insulating your loft for use as a room costs significantly more than standard loft insulation, so consider whether you need this type of insulation before going ahead with an installation.

How Much Does Room in Roof Insulation Cost?

This insulation can cost more than standard loft insulation, because you’ll need to insulate the room in a way that keeps the attic warm while allowing for the rest of the home to feel the benefit of increased thermal efficiency.

The entire cost is likely to be around £2000 for a typical property. You can expect to pay slightly more or less depending on the size of the room you’re insulating, plus the type of insulating material that you choose. An insulation material such as foam insulation is highly effective for insulating the likes of attic rooms, loft rooms, loft conversions, and for use on sloping ceilings, but is generally a more expensive option.

Can I Install Room in Roof Insulation Myself?

While a DIY installation in a loft room is possible, it’s not advisable, especially not without previous experience with similar projects. You’d need to make sure all the insulation work meets building regulations, including fire resistance and ventilation restrictions. You’d also have to maximise the efficiency of the insulation and avoid the risk of damp.

While it’s understandable to want to reduce labour costs, a DIY installation could cost you more in the long run if you have to pay for problems that arise as a result of incorrect installation, such as damp problems and mould.

Things to Consider Before Installing Room in Roof Insulation

There are a few things it’s worth checking before installing insulation in a loft room, as well as regulations regarding what qualifies for this type of insulation.

There are a few things it’s worth checking before installing insulation in a loft room, as well as regulations regarding what qualifies for this type of insulation.

Things to consider include:

  • The roof space should not be damaged. Check for flaking or rotting timber, mould and damp, or faulty electrical connections.
  • Half of the vertical walls should be lower than 1.8 metres. If more than half of the walls are 1.8 metres high, the loft will be considered as an extra storey, which complicates the project.
  • There must be a standard fixed staircase for access – ladders are not acceptable. If you don’t already have a staircase in your loft, install one before the insulation process.
  • All elements of the loft should be properly ventilated.
  • You should reduce thermal bridging before getting started. Leaving cold spots in the room can lead to damp and mould, so pay attention to detailing around elements such as skylights and chimneys.


Can I Install Room in Roof Insulation for Free?

In many cases, yes. The government is on a mission to make homes more energy efficient, which would reduce the national carbon footprint as well as helping consumers save money on heating bills.

Roof insulation grants are available under the government’s Energy Companies Obligation (ECO) and Great British Insulation Schemes. Under these you could be eligible for free funding which could cover all or part of the costs of achieving a roof insulation grants room for your home.

If you live in an older property with a loft or attic that was originally built without roof insulation, or the insulation is inadequate, you can get a grant to cover an insulation upgrade. In some cases, you might have to pay a small contribution, but the cost will be significantly reduced from the typical amount you’d expect to pay for installation.
If you claim any of the following benefits, you’ll likely be considered for a government insulation grant:

  • Pension Credit
  • Universal Credit
  • Income based Jobseekers allowance
  • Income related
  • Employment & Support Allowance
  • Income Support
  • Housing Benefit
  • Tax Credits (Child or
  • Working Tax Credit)

Additionally, you could also qualify for grant funding under ECO4 Flex rules if your household has an annual income below a certain threshold (usually £31,000). Eligibility for ECO4 is also dependent on the energy efficiency rating (EPC) of your home, with homes rated D, E, F or G likely to qualify. Funding is also available in Scotland for privately funded insulation installations from Home Energy Scotland.

How Long Does Room in Roof Insulation Last?

One of the biggest advantages of insulation is longevity. Once you’ve installed your insulation, you can expect it to last for many decades. Your insulating material will effectively pay for itself many times over during its lifespan in terms of the annual heating bills savings.

If your insulation has been installed, but you haven’t noticed a difference or you’re seeing signs of damp and condensation, check whether the insulation has been properly installed. You can do this with the help of a professional.

What If I Don’t Have a Loft Conversion?

If you want to make your home more thermally efficient in order to minimise heat loss and save energy, but you don’t need to use your roof as a living space, you can instead opt for regular loft insulation. Some of the most popular types of loft insulation include blanket insulation, rigid boards, blown fibre, and loose-fill, all of which do a more than adequate job of trapping heat

If you don’t currently use your loft as a room but would like to, you’ll have to convert it properly with the help of a professional installer before insulating it.

How to Prepare Your Roof for Room in Roof Insulation

Before the installers arrive, you’ll need to clear out your entire loft space so it’s suitable for working in. Seal off air leaks around chimneys, wires, windows, pipes, and ducts that would allow air to escape.

If any part of your roof is leaking, you’ll need to fix this, as well as boxing off light fixtures.If your property has damp or condensation problems in the loft, avoid getting it insulated until the problem is fixed.

How to Choose the Right Insulation Installer for Your Project

Room in roof insulation is a more challenging insulation job than other types of insulation, so getting the right professional for the job is crucial. This type of installation really should not be undertaken as a DIY project, unless by highly competent people.

Enquire with Insulation Advisor, and we’ll put you in touch with trusted installers who will provide you with a competitive quote for insulating your loft space.

On This Page
Get Your Insulation Quote

Recent Articles