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Choose A Rainscreen Cladding Contractor After A Failed EWS Survey

Written by Advanced Glass | Dec 3, 2025 10:00:00 AM

The External Wall System (EWS) survey process, often referenced as an EWS1 form, is a critical assessment tool for residential buildings with cladding. Introduced in December 2019, the process provides lenders, valuers, and building owners with a consistent framework for evaluating external wall fire risk. Understanding these surveys is essential when delivering remediation projects or managing building safety compliance under the Building Safety Act 2022, especially when expectations have been raised for higher-risk buildings over 18 metres.

What Is An EWS Survey & How To Interpret Results?

An EWS survey evaluates the materials and construction of a building's external wall system, including cladding, insulation, balconies, and fire barriers, to determine potential fire risks and ensure it meets current UK government fire safety standards.

​The outcome is recorded on an EWS1 form, which categorises the building under two routes:

  • Option A: The external wall does not contain any or contains limited amounts of combustible materials, with subcategories detailing specific materials used.

A1: Non-combustible materials and no remediation required.

A2: Limited combustibility materials and no remediation required.

  • Option B: The external wall includes combustible elements, requiring further risk assessment and possible remediation.

B1: Risks are managed without remediation.

B2: Significant fire safety concerns and remediation required. This rating has major implications, triggering complex works programmes involving cladding replacement, insulation upgrades, and verified fire stopping.

​​The Impact Of A Failed EWS1

A B2 rating can have immediate consequences for leaseholders, including difficulties selling or remortgaging, and in many cases, £0 valuations. For contractors, this translates into urgent demand for large-scale remediation schemes, often with substantial financial scrutiny from all parties involved as projects of this nature now carry added complexity under the Building Safety Act, which increases accountability and requires stricter evidence trails at handover.

Common Reasons For Failed EWS Ratings

While the specific reasons for a failed EWS1 rating can vary, common factors include:

  • Combustible materials in cladding or insulation: The use of flammable materials such as aluminium composite panels (ACPs) or high-risk insulation.
  • Improper installation: Poor workmanship during installation can create vulnerabilities in fire resistance.
  • Ageing systems: Older materials may no longer meet modern fire safety standards.
  • Lack of fire breaks: Missing or poorly installed fire stops/cavity barriers can increase the risk of a fire spreading.
  • Lack of documentation: Insufficient documentation demonstrating fire performance.​ In line with the new safety regime introduced by the Building Safety Act, EWS surveys are now subject to closer scrutiny, and the documentation provided must be thorough enough to withstand regulator and client review.

​Each of these issues has direct cost and compliance implications. Failing to demonstrate adequate fire performance is not only a technical shortcoming but also a regulatory risk, requiring careful planning and contractual oversight.

​Remediation And Funding Options

Remediation generally involves the removal and replacement of unsafe wall systems, ensuring correct fire stopping and the use of compliant rainscreen cladding. While costs can be significant, government schemes such as the Building Safety Fund and the Cladding Safety Scheme provide financial support for eligible buildings, particularly those over 18m in height. Contractors should be prepared to work within these frameworks, providing the evidence needed to access funding.

The Role of Rainscreen Cladding Contractors In Remediation

IF you’ve failed your EWS1 survey, this is where selecting the right contractor really matters, as quality counts. When choosing your contractor, there are a few things to consider. A reliable partner should:

  • Demonstrate experience removing and replacing unsafe cladding and insulation.
  • Provide full documentation of compliance with fire performance standards.
  • Address common failure points, such as poor workmanship and inadequate fire stops.
  • Collaborate effectively with fire engineers, façade consultants, and QS teams to keep projects on time and within budget.

Next Steps

​At Advanced Glass, we can help you navigate the challenges of EWS remediation. From initial surveys to full rainscreen cladding replacement, we bring technical expertise, compliance assurance, and a proven track record of delivering large-scale façade projects. With our experience, expertise, and commitment to safety, we’re ready to help you overcome these challenges. Contact us today to discuss your project needs.

​Image source: Canva