NAO Report November 2024:98% failure rate revealed

External Wall Insulation

External Wall Insulation Removal Cost Guide 2024

Complete cost breakdown for removing failed external wall insulation (EWI). Understand what you'll pay based on property size, location, and extent of damage. Get accurate quotes from vetted contractors.

Average Cost Range
External wall insulation removal typically costs between £8,000 and £25,000 depending on property size and damage extent. This includes removal, disposal, wall repair, and finishing.

Quick Cost Summary

£8,000 - £12,000
Small Semi-Detached
2-3 bed | 60-80m² wall area
£12,000 - £18,000
Detached House
3-4 bed | 100-140m² wall area
£18,000 - £25,000+
Large Detached
4-5 bed | 150m²+ wall area

Complete Cost Breakdown

External wall insulation removal is a major undertaking involving multiple trades and stages. Here's a detailed breakdown of all costs involved:

1. Assessment and Surveying (£300 - £800)

Initial damp survey£200 - £400
Structural survey (if required)£400 - £600
Thermal imaging assessment£150 - £300
Air quality/mould testing£100 - £250

Professional surveys are essential for insurance claims and determining the full extent of damage. Many homeowners need multiple surveys.

2. Scaffolding and Access (£1,500 - £4,000)

Full house scaffolding (4-6 weeks hire)£1,200 - £2,500
Scaffold delivery and erection£400 - £800
Scaffold dismantling£300 - £600
Edge protection and safety netting£200 - £400

Scaffolding costs vary by region and property height. London and South East typically 20-30% higher than national average.

3. EWI Removal Labour (£4,000 - £10,000)

This is the main cost component. EWI removal is labor-intensive and requires specialist skills to avoid further damage to the underlying wall structure.

Render removal (per m²)£20 - £35/m²
Insulation board removal (per m²)£15 - £25/m²
Fixing/mechanical fastener removal£8 - £12/m²
Adhesive removal and wall preparation£10 - £18/m²
Window reveal/trim restoration£150 - £300 per window

4. Waste Disposal and Skip Hire (£600 - £1,500)

Skip hire (multiple loads typically needed)£400 - £1,000
Hazardous waste disposal (if asbestos-containing)£500 - £2,000
Site cleaning and vacuum removal£200 - £400
Asbestos Warning
Some older EWI systems (pre-2000) may contain asbestos fibers in render or adhesives. Testing is mandatory, and specialist removal can add £2,000-£5,000 to total costs.

5. Wall Repair and Restoration (£2,000 - £8,000)

Once EWI is removed, underlying walls often require repair work, especially if moisture damage has occurred.

Brick pointing and repair (per m²)£25 - £45/m²
Render patching and smoothing£15 - £30/m²
Damp-proof membrane installation£20 - £40/m²
Cavity wall tie replacement£10 - £20/m²
Breathable waterproof coating£15 - £25/m²

6. Decorative Finishing (£1,500 - £5,000)

External masonry paint (2 coats)£12 - £20/m²
Brick cleaning and restoration£8 - £15/m²
Traditional lime render (heritage properties)£40 - £70/m²
Window/door trim replacement£100 - £250 per opening

Example Cost Calculations

Example 1: Small Semi-Detached House

Property Details
2-bed semi, 70m² external wall area, South East England
£10,450
Initial survey and assessment£400
Scaffolding (4 weeks)£1,800
EWI removal (70m² @ £55/m²)£3,850
Waste disposal£700
Wall repair and pointing£2,100
Masonry paint and finishing£1,200
Contingency (5%)£400

Example 2: Detached House with Moderate Damage

Property Details
4-bed detached, 120m² wall area, damp damage, Midlands
£15,800
Full survey package (damp + structural)£700
Scaffolding (6 weeks, full house)£2,800
EWI removal (120m² @ £58/m²)£6,960
Waste disposal (multiple skips)£1,100
Wall repair and damp treatment£2,800
Repointing and finishing£1,800
Contingency (10% due to damage)£1,440

Example 3: Large Detached with Severe Damage

Property Details
5-bed detached, 180m² wall area, extensive damage, London
£24,700
Comprehensive survey and testing£1,200
Scaffolding (8 weeks, London rates)£4,200
EWI removal (180m² @ £65/m²)£11,700
Waste disposal and site management£1,500
Extensive wall repair and remediation£4,200
Premium finishing and restoration£2,700
Project management and contingency£2,200

Factors That Affect EWI Removal Cost

1. Property Size and Wall Area

Costs scale with the amount of wall surface requiring treatment. Measure or estimate your external wall area (height × perimeter, minus windows/doors) to get accurate quotes.

2. Type of EWI System Installed

Polystyrene (EPS) boards with thin coat renderEasier - Lower cost

Most common ECO4/GBIS system. Relatively straightforward removal.

Mineral wool boards with thick renderModerate - Mid cost

Heavier render layers require more labor. More dust generation.

Phenolic foam or rigid insulation with mechanical fixingsHarder - Higher cost

Extensive mechanical fixings penetrate brickwork. Removal causes more damage.

3. Extent of Underlying Damage

Properties where moisture has penetrated and damaged brickwork, mortar, or cavity wall ties will require extensive remediation beyond simple removal. This can add 30-50% to costs.

4. Access and Property Characteristics

Cost-Increasing Factors

  • Three-story or taller buildings
  • Limited access for vehicles/equipment
  • Listed building or conservation area
  • Complex architectural details
  • Urban locations (higher labor rates)

Cost-Reducing Factors

  • Single or two-story property
  • Good vehicle access for equipment
  • Simple rectangular design
  • Minimal damage to underlying walls
  • Rural or lower-cost regions

5. Regional Price Variations

Regional Cost Multipliers (vs National Average)

London and Inner South East+25% to +40%
Outer South East, East Anglia+15% to +25%
South West, MidlandsNational average
North West, Yorkshire-5% to -15%
North East, Scotland-10% to -20%
Wales, Rural Areas-15% to -25%

Payment and Financing Options

1. Insurance Claims

If you have buildings insurance or legal expenses insurance, check whether EWI removal and remediation are covered. Some policies cover "sudden and unforeseen damage" which may apply if damp/mould appeared unexpectedly.

Insurance Claim Success Rate
Approximately 30% of homeowners successfully claim some or all EWI removal costs through insurance, particularly if they can demonstrate the installer's negligence or the scheme's failure to meet standards.

2. Compensation Claims

Many homeowners pursue compensation from the original installer, Trustmark, or the government scheme (ECO4/GBIS). Successful claims can cover 70-100% of removal and remediation costs.

3. Payment Plans from Contractors

Some specialist EWI removal contractors offer payment plans or staging options:

  • Deposit on booking: 10-20% to secure dates
  • Progress payments: 30% on scaffolding, 40% on removal completion, 30% on finishing
  • Deferred payment: Wait for compensation claim settlement (higher fees apply)

4. Home Improvement Loans

If you cannot claim through insurance or compensation, consider:

  • Home improvement loans (unsecured, typically £5,000-£25,000)
  • Remortgaging or secured loans against property equity
  • Local authority assistance schemes (check with your council)
  • Credit unions for lower-interest borrowing options

What's Included vs Extra Costs

Typically Included in Quoted Price

  • All labour for removal and basic wall repair
  • Scaffolding hire for agreed duration
  • Waste disposal (non-hazardous)
  • Materials for standard wall finishing
  • Public liability insurance during works

Often Charged as Extras

  • Pre-work surveys and assessments
  • Asbestos testing and removal
  • Structural repairs beyond cosmetic work
  • Damp-proof treatments and membranes
  • Premium finishing options (lime render, specialist paints)
  • Scaffolding extensions beyond agreed duration
  • Making good internal walls (plaster, decoration)

How to Get Accurate Quotes

Information to Provide

When requesting EWI removal quotes, provide contractors with:

  1. 1.Property details: Type, number of stories, approximate wall area or dimensions
  2. 2.EWI type: If known - polystyrene/mineral wool/other, thickness, render type
  3. 3.Installation date: When EWI was installed and under which scheme
  4. 4.Current problems: Damp, mould, cracking - with photos if possible
  5. 5.Access details: Location, parking, any access restrictions
  6. 6.Desired finish: Standard render/paint, brick restoration, or other preferences

Questions to Ask Contractors

Experience & Qualifications

  • How many EWI removal projects have you completed?
  • Do you have specific EWI remediation accreditations?
  • Can you provide references from recent similar projects?
  • What insurance do you carry (public liability, professional indemnity)?

Scope & Process

  • Exactly what's included in your quoted price?
  • How long will the project take from start to finish?
  • What happens if you discover additional damage during removal?
  • Do you provide a guarantee/warranty on your remediation work?

Get Free EWI Removal Quotes

We connect homeowners with vetted EWI removal specialists who understand the complexities of failed government scheme installations. Get multiple quotes, compare prices, and choose the right contractor for your project.

Frequently Asked Questions

Can I remove EWI myself to save money?

Not recommended. EWI removal requires specialized equipment, safety measures (working at height), proper waste disposal, and knowledge of underlying wall structures. DIY removal often causes additional damage and voids any potential insurance/warranty claims.

How long does EWI removal take?

Typical timescales: Small semi-detached (2-3 weeks), Detached house (3-5 weeks), Large detached (5-8 weeks). Weather and unexpected damage can extend timelines.

Do I need planning permission to remove EWI?

Usually no, as you're returning the property to its original state. However, if you're in a conservation area or have a listed building, consult your local planning authority first.

Will removing EWI affect my EPC rating?

Yes, your EPC rating will likely decrease. However, the benefits of eliminating damp/mould problems typically outweigh EPC concerns. You can improve energy efficiency through alternative methods (loft insulation, double glazing, etc.) without the risks of EWI.