Internal Wall Insulation Removal: Process, Cost & Contractors
Removing internal wall insulation is more disruptive than other types but often necessary when causing severe damp or condensation. Understand the full process, realistic costs (£4,000-£15,000), and what to expect during removal.
Why Remove Internal Wall Insulation?
Common Reasons for Removal
- Severe condensation and black mould growth
- Cold bridging at junctions causing persistent damp
- Interstitial condensation trapped behind boards
- Loss of room space (100-150mm per wall)
- Damage to original walls during installation
- ECO4/GBIS installation causing severe problems
- Need to restore original character (period properties)
When NOT to Remove
- Minor condensation solvable with ventilation upgrade
- IWI functioning well but different aesthetic preferred
- Cost of removal exceeds property value increase
- Problems can be remediated for less money
Get a professional survey (£350-£600) to confirm removal is necessary before committing to this expensive and disruptive process.
IWI Removal Process: Step-by-Step
Pre-Removal Survey & Planning
Specialist assesses the IWI system, wall condition beneath, and plans removal approach. Identifies any asbestos risks (older properties) or listed building consent requirements.
What's assessed:
- • Type of IWI system (board-on-dab, stud wall, hybrid)
- • Extent of removal (full rooms vs partial walls)
- • Condition of original wall beneath
- • Services to disconnect (electrics, radiators)
- • Access and waste disposal logistics
Timeline: 1-2 days
Includes survey, quote preparation, and planning permissions if needed.
Cost: Usually included in removal quote
Room Clearance & Protection
All furniture, carpets, and belongings must be removed. Dust sheeting installed to protect floors and adjacent rooms. Services isolated (electrics, water if needed).
Your responsibilities:
- • Remove all furniture and belongings
- • Arrange alternative accommodation (if extensive)
- • Provide access to water and power
- • Secure pets and valuables
Contractor provides:
- • Dust containment screens
- • Floor protection
- • Waste skip (8-20 cubic yards)
- • Vacuum extraction equipment
Insulation Board/System Removal
The messy part. Insulation boards, plasterboard, and fixings are removed. Method depends on installation type - board-on-dab adhesive is particularly difficult.
Removal methods:
- • Stud walls: Dismantle framework, remove boards
- • Board-on-dab: Pry boards off, scrape adhesive
- • Mechanical fixings: Unscrew/cut fixings
- • Hybrid systems: Combination approach
Timeline: 2-5 days
Depends on room size and system type. Board-on-dab takes longest.
Noise level: Very high - neighbors should be warned
Wall Surface Preparation
Original wall is revealed - often damaged from installation. Adhesive residue scraped off, holes from fixings filled, surface prepared for new finish.
Common damage found:
- • Plaster knocked off during IWI installation
- • Holes drilled for mechanical fixings
- • Damp damage from condensation
- • Crumbling brick/stone (if directly plastered)
Timeline: 1-3 days
Depends on condition beneath. May need re-plastering or damp treatment.
Additional cost: £15-30/m² for re-plastering
Replastering & Making Good
Walls are replastered with breathable lime or gypsum plaster. Services reinstalled (sockets, radiators). Skirting boards and architraves refitted or replaced.
What's included:
- • Full re-skim or two-coat plaster
- • Electrical sockets/switches reinstalled
- • Radiators refitted and tested
- • Skirting boards replaced/refitted
- • Mist coat applied (if in quote)
Timeline: 3-5 days
Includes plastering, drying time, and second coat if needed.
Drying: 7-14 days before decorating
Decoration & Final Finishing
Usually not included in removal quotes. You'll need to arrange decoration yourself or get separate quotes. Allows you to restore original character or modernize.
Your costs:
- • Painting/wallpapering: £10-20/m²
- • New carpets/flooring: £20-80/m²
- • Replacement furniture if damaged
- • New curtains (larger windows revealed)
Timeline: 1-2 weeks
After plaster fully dried. Can take longer if ordering materials.
Budget: £1,000-£5,000 for full room redecoration
IWI Removal Cost Breakdown
| Property Type | Removal Only | Removal + Replaster | Full Package |
|---|---|---|---|
| 1-Bed Flat | £2,000 - £4,000 | £3,500 - £6,000 | £5,000 - £8,000 |
| 2-Bed House | £4,000 - £7,000 | £6,500 - £10,000 | £9,000 - £13,000 |
| 3-Bed House | £6,000 - £10,000 | £9,000 - £14,000 | £12,000 - £18,000 |
| 4-Bed House | £8,000 - £12,000 | £12,000 - £17,000 | £15,000 - £22,000 |
Removal Only includes:
- • IWI board/system removal
- • Adhesive scraping
- • Waste disposal
- • Basic wall preparation
+ Replaster adds:
- • Full wall replastering
- • Services reinstallation
- • Skirting refitting
- • Mist coat primer
Full Package adds:
- • Full decoration
- • New flooring
- • All finishing touches
- • Move-in ready
Cost factors: Board-on-dab removal costs 30-40% more than stud walls due to labor intensity. Listed buildings may require specialist plasterers (+20-30%). Access issues (no parking, upper floors) add 10-15%.
Living Through IWI Removal
Expect Significant Disruption
IWI removal is the most disruptive insulation removal type. Unlike cavity wall or spray foam (external work), this happens inside your living space.
- • Dust: Extreme levels despite containment. Everything will need deep cleaning.
- • Noise: 8+ hours/day of loud power tools, breaking plaster, disposal.
- • Access: Contractors in your home 6-10 hours daily for 1-2 weeks.
- • No use of rooms: Affected rooms completely unusable during work.
- • Services off: Heating/electrics in rooms isolated for safety.
Consider Alternative Accommodation If:
- • Removing IWI from entire house
- • Young children or vulnerable occupants
- • Health conditions affected by dust
- • Working from home (impossible during works)
- • Pets that stress easily
Can Stay If:
- • Only 1-2 rooms affected
- • Work can be phased over weekends
- • You can tolerate disruption
- • Alternative rooms to use
- • Strong containment measures agreed
Need IWI Removed?
Get detailed quotes from specialists experienced in internal wall insulation removal. Compare costs for removal-only vs full restoration packages.