Internal Wall Insulation Grant (Drylining) — Up to €4,500 from SEAI
Internal wall insulation (drylining) is an alternative to external wall wrap — especially useful for terraced homes, conservation areas, or where external changes are not practical. SEAI offers grants up to €4,500 depending on property type. This guide covers who it usually suits, what to watch out for, and how to apply correctly.
Check My HomeWhat This Grant Is
The SEAI internal wall insulation grant covers the installation of insulation boards or a studded frame system on the inside surface of your external walls — commonly known as drylining. Insulation material is bonded to or packed behind a plasterboard lining, reducing heat loss through the walls. It is an alternative to external wall insulation (EWI), which is applied to the outside of the building.
Internal (Drylining) — Usually Better When:
- Terraced or mid-terrace home (less external wall exposed)
- Home is in a conservation area or is a protected structure
- External appearance must not change
- Budget is tighter — typically lower installation cost than EWI
External (EWI) — Usually Better When:
- Detached or semi-detached with large exposed wall area
- Preserving internal floor area is a priority
- Home needs external render refresh anyway
- Maximising energy performance improvement
Current Support Amount
€4,500
Detached
€3,500
Semi-detached / End of terrace
€2,000
Mid-terrace
€1,500
Apartment
Grant amounts from SEAI.ie, March 2026. Always verify current rates at seai.ie before applying.
Who It Usually Suits
Terraced and mid-terrace homes with solid walls
Many pre-1940 terraced homes have solid stone or brick walls with no cavity. Cavity fill is not possible — drylining is one of the few wall insulation options available for these homes.
Homes in conservation areas or with protected structure status
External wall insulation changes the appearance of your home. Planning authorities may not permit EWI in conservation areas or for protected structures. Drylining keeps the exterior unchanged.
Homeowners with a tighter budget
Internal drylining is typically less expensive to install than external wall insulation. The SEAI grant is also lower, but the net cost to the homeowner is often lower too.
Homes where some room size reduction is acceptable
Drylining adds 50–100mm per treated wall. If certain rooms can absorb this — a large living room or hallway — internal insulation can be a practical choice.
Main Eligibility Points
Home built before 2011
Must have been built and occupied before 31 December 2010.
No prior internal wall insulation grant
If this grant has already been claimed at the property (by you or a previous owner), you cannot claim again.
SEAI-registered contractor required
Only contractors registered with SEAI for internal wall insulation are eligible. Verify at seai.ie/contractor-register before signing anything.
Apply before work starts
Written approval from SEAI must be received before the contractor begins any work — including preparatory work.
Apartments: OMC approval likely needed
Owner management company approval is typically required before works in apartments. Factor this in early.
Do not start work before receiving written approval from SEAI.
What Commonly Blocks or Complicates It
Room size will be noticeably reduced
Drylining adds 50–100mm of thickness per treated wall. In smaller rooms — box rooms, narrow hallways, small kitchens — this is a meaningful reduction. Consider this carefully when planning which rooms to treat.
Sockets, switches, and radiators must be relocated
Electrical sockets and light switches on treated walls need to be repositioned, as do radiator brackets. Include electrical work in your quotations — costs can add up.
Not suitable for wet rooms without specific systems
Standard drylining is not appropriate for bathrooms or wet rooms without moisture-resistant board and detailing. Discuss this with your contractor before proceeding.
Cold bridges at reveals and junctions require care
Internal drylining only covers flat wall sections. Window reveals, floor/ceiling junctions, and internal corners require careful detailing to prevent cold spots and potential condensation. Confirm how your contractor handles this.
Disruption is significant during installation
Rooms being drylined must be completely cleared. Work can take several days per room. If treating multiple rooms, plan for meaningful disruption to daily life.
Typical Cost vs Support
| Item | Typical range |
|---|---|
| Internal wall insulation — semi-detached (all external walls) | €4,000–€12,000 |
| SEAI internal wall insulation grant (semi-detached) | −€3,500 |
| Your indicative net cost | ~€500–€8,500 |
Wide cost range due to property size, wall area, number of rooms, and whether electrical repositioning is needed. Always get 3 quotes from SEAI-registered contractors.
Correct Application Process
Get quotes from SEAI-registered contractors
Find contractors registered with SEAI specifically for internal wall insulation. Get at least 2–3 written quotes. Ask each to confirm what walls they are pricing, how socket and radiator moves are handled, and how cold bridges at reveals are treated.
Apply for grant approval at hes.seai.ie before work starts
Submit your application online. You will need your MPRN (11-digit number starting with '1' on your ESB electricity bill), property details, and contractor information. Wait for written approval before proceeding.
Receive written approval from SEAI
SEAI issues written approval, typically within a few weeks. Work cannot start until this letter is received. Keep it on file.
Installation is carried out
Your SEAI-registered contractor carries out the drylining works. Rooms being treated will need to be cleared. Electrical repositioning may run simultaneously with a registered electrician.
Grant is processed
Your contractor submits completion documentation to SEAI. The grant is paid. For One Stop Shop projects, the grant is deducted upfront by the provider.
Do not start installation before written SEAI approval. This disqualifies your grant with no appeal process.
Common Mistakes
Starting installation before receiving written SEAI approval
Using a contractor not registered with SEAI for internal wall insulation specifically
Not budgeting for electrical repositioning costs (sockets, switches, radiator brackets)
Failing to detail cold bridges at window reveals and floor/ceiling junctions
Drylining rooms too small to absorb the thickness reduction without significant loss of usable space
Related Grants and Routes
External Wall Insulation Grant (up to €8,000)
For homes where external changes are acceptable. Higher grant, higher performance improvement — often better for detached and semi-detached homes.
Read the EWI guide →
One Stop Shop (up to 50% of project cost)
If doing a full retrofit to B2 BER, the OSS scheme may cover more than individual grants. Wall insulation can be included in an OSS project.
Read the OSS guide →
Apply at SEAI.ie
All applications through the official SEAI portal.
Check All Support Options for Your Home
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