Room in Roof Insulation Grants 2026

What counts as a room in roof?

A “room in roof” is loft space that has been converted into living space — an attic bedroom, a converted top floor, a dormer extension, a home office in the eaves. The defining feature, for grant purposes, is that the roof space is habitable and finished, so there is no open joisted floor to lay insulation across.

Typical examples:

• A loft conversion with a staircase, sloping ceilings following the line of the rafters, and short vertical walls at the sides.
• A dormer, where part of the roof has been built out to create headroom, with flat ceilings and vertical dormer cheeks.
• A 1930s or post-war chalet bungalow built with rooms in the roof from the start.
• A boarded and plastered attic room that was never formally converted, but is used as a bedroom.

If you can still see the joists and you are walking on boards laid over rockwool, that is a loft, and you want loft insulation instead. If it is plastered, decorated and heated, it is a room in roof.

Why it is treated differently from loft insulation

Ordinary loft insulation is the cheapest measure in the whole retrofit toolkit: rolls of mineral wool laid over and between the ceiling joists, two to four hours, no mess, and 270mm is the recommended depth. Nobody has to decorate afterwards.

A room in roof has none of those advantages. The heat-losing surfaces are the surfaces of the room you are standing in:

• the sloping ceilings that follow the rafters;
• the flat ceiling at the top, between the purlins;
• the knee walls (sometimes called dwarf or stud walls) at the sides of the room;
• the eaves voids behind those knee walls, which are usually completely uninsulated and open to the cold;
• the gable walls and dormer cheeks.

Insulating all of that means working inside a finished room, and it is why room-in-roof insulation is priced and scored separately from loft insulation under every scheme. It is a bigger job, it costs several times as much, and it disturbs the household — but it also targets a room that is very often the coldest in winter and the hottest in summer, because it sits directly under the roof.

There is one more reason the distinction matters: many conversions, especially older or unregulated ones, were finished with little or no insulation at all. A room that was plasterboarded straight onto the rafters in 1985 can be losing heat as fast as an uninsulated solid wall.

What ECO4 and the Warm Homes: Local Grant fund

Room-in-roof insulation (often abbreviated RIRI by installers) is a standard, recognised measure under both live schemes. Where you qualify, the scheme pays for the assessment, the materials, the labour and making good — not a contribution towards it.

• ECO4: funds room-in-roof insulation as part of a whole-house package. Because it delivers a large improvement in a property's energy rating, it scores well and is one of the measures suppliers actively look for. ECO4 was extended once and closes on 31 December 2026, with no carry-over and no ECO5.
• Warm Homes: Local Grant: England only, April 2025 to March 2028, delivered through councils and their appointed installers. It counts against the £16,600 energy-performance spend cap, which is averaged across a council's project — room-in-roof work sits comfortably inside that, unlike a full external wall wrap.
• LA Flex: a council declaration route into ECO4 for households with no qualifying benefit. Same measure, different front door, and it ends when ECO4 does.

The old Great British Insulation Scheme also funded room-in-roof insulation, and you will still find pages recommending it. Its GOV.UK referral route closed on 31 March 2026; the three routes above are what is left.

Room in roof insulation grants: who qualifies in 2026

Three routes, and you only need to clear one of them.

ECO4 — qualifying benefits

Someone in the household must receive one of the qualifying benefits: Universal Credit, Pension Credit (Guarantee or Savings Credit), Income Support, income-based Jobseeker's Allowance, income-related Employment and Support Allowance, Housing Benefit, or Child Benefit within the scheme's income thresholds. Disability benefits such as PIP, DLA and Attendance Allowance do not qualify on their own: the household also needs one of the means-tested benefits above, or an LA Flex route. The property normally needs an EPC rating of D or below, which an uninsulated converted loft makes fairly likely. See our full guide to ECO4 eligibility.

Warm Homes: Local Grant — England, no benefit needed

One of three routes must apply: gross household income under £36,000 a year before tax; someone in the home receiving Universal Credit, Pension Credit, Housing Benefit, Income Support, income-based JSA or income-related ESA; or a home in a postcode among the most income-deprived 20% in England. The home must be rated EPC D to G and be owner-occupied or privately rented with the landlord's consent — privately rented F and G homes need a registered MEES exemption. Social housing is not eligible; park homes are. Councils must contact an eligible household within 10 working days of a referral, and not every council joined the programme.

LA Flex — your council's own criteria

Councils publish a statement of intent setting out who they will declare eligible, typically on low income, vulnerability to cold, or a referral from a health or support service. No benefit claim is required.

Scotland and Wales

ECO4 applies across Great Britain, so a Scottish or Welsh household on qualifying benefits can be funded through it. The Warm Homes: Local Grant is England only. Scotland's equivalent is Warmer Homes Scotland via Home Energy Scotland; Wales has the Warm Homes Nest scheme.

Nobody is guaranteed a grant. Funding is finite, delivery is postcode by postcode, and the assessment can conclude that another measure comes first.

How room-in-roof insulation is installed

Almost all of the work happens inside the room. A typical specification covers five areas:

1. Sloping ceilings. Insulation is fitted between the rafters, or insulated plasterboard is fixed over them, and skimmed. A ventilation gap is left above the insulation so the roof timbers can still breathe — this is not optional, and a good installer will not skip it.
2. Flat ceiling. The horizontal section at the top of the room is insulated above or below, depending on access.
3. Knee walls. The short vertical walls at the sides are insulated, usually with rigid board or insulated plasterboard.
4. Eaves voids. The triangular spaces behind the knee walls — often used as cupboards — are insulated at floor and wall level, because cold air otherwise circulates freely through them.
5. Gables and dormer cheeks. Any vertical wall directly exposed to outside is insulated in the same way.

Where there is safe access, some of the work in the eaves voids can be done from behind, which reduces the mess inside. Where there is not, hatches are formed, insulated and closed up again.

Ventilation is checked at the same time. Insulating a room in roof tightens the building fabric, so the specification often includes extract ventilation or trickle vents to keep moisture moving — particularly if the room is a bedroom. Grant work must be carried out by a TrustMark-registered installer to the PAS 2035 retrofit standard, with a retrofit assessor and coordinator overseeing the design.

Disruption, timescale and what to expect

This is a more intrusive job than any other insulation measure short of internal wall insulation. Realistically:

• Time on site: usually three to five days for a standard converted loft, longer for a large dormer or a complicated roof.
• The room is out of use for that period. Furniture has to be moved out or sheeted, and anything stored in the eaves cupboards has to come out first.
• There will be dust from cutting board and skimming, and there is usually a drying-out period before decoration.
• Redecoration is on you. The installer makes good the plaster; painting and wallpapering afterwards is the household's cost. Factor that in before you say yes.
• You lose a little space. Insulated plasterboard over the slopes takes typically 50–100mm off each surface, which is noticeable in a room that was already tight on headroom.

In exchange, the room becomes usable in winter. Households commonly report that an attic bedroom that was previously unheatable holds temperature normally afterwards, and that summer overheating drops too, because the insulation works in both directions.

How much does it save?

The saving depends entirely on how bad the starting point was, and there is no single credible national figure for room-in-roof insulation the way there is for lofts and cavity walls. What can be said with confidence is that it is one of the higher-impact measures in the ECO4 toolkit, precisely because so many converted lofts have little or no insulation and sit directly beneath the roof.

For comparison, the Energy Saving Trust puts standard loft insulation at up to £590 a year for a detached house and cavity wall insulation at up to £595 a year. A converted loft that was never insulated is losing heat over a comparable area, so the improvement is in the same territory — but the honest answer is that your retrofit assessment, which models your actual property, is the only figure worth acting on.

Privately, room-in-roof insulation typically costs several thousand pounds, which is why the grant route matters so much for this particular measure.

How to apply

1. Check all three routes at once. The eligibility checker covers ECO4, LA Flex and the Warm Homes: Local Grant in a single pass. In England you can also apply directly through the government's checker on GOV.UK.
2. Have your evidence ready. Benefit award letters or proof of household income, your EPC, and written landlord consent if you rent.
3. Say that you have a converted loft. Say it early and say it plainly — “room in roof” is the term installers use, and it stops you being booked in for a standard loft top-up that cannot physically be done.
4. Whole-house assessment. An assessor surveys the property under PAS 2035 and a retrofit coordinator specifies the package, which may combine room-in-roof work with cavity wall, solid wall or underfloor insulation and ventilation improvements.
5. Install and sign-off. Three to five days on site for most conversions, then TrustMark lodgement and usually a new EPC reflecting the improvement.

With ECO4 closing on 31 December 2026, allow time: the work has to be completed before the deadline, not merely approved.