External Wall Systems and EWS1: What You Need to Know

14 November 2025

External wall systems – everything from cladding to insulation – play a crucial role in building safety, insurance, and compliance. At TCL Chartered Surveyors, we often approach EWS1 assessments as part of our Defect Diagnosis and Planned Preventative Maintenance (PPM) services. This ensures landlords and commercial property managers not only understand risk but can plan for remediation and ongoing maintenance.

What is an EWS1 Assessment?

An EWS1 form provides a professional assessment of a building’s external wall system, primarily for fire safety. Lenders, insurers, and leaseholders rely on it to understand risk. A correctly completed assessment by an experienced surveyor ensures the findings are accurate, defensible, and actionable.

Why Experience Matters

External wall systems can be complicated, and not all surveyors have the expertise to assess them thoroughly. Our team has decades of experience across high-rise residential, commercial, and mixed-use properties. We identify risks early, guide remediation where needed, and ensure assessments are reliable for all stakeholders.

Key Benefits of an EWS1 Assessment

  • Compliance and confidence: Meet lender and insurer requirements with a robust, professional opinion.
  • Risk management: Highlight potential issues before they become costly problems.
  • Maintenance planning: Feed findings into planned preventative maintenance programmes.
  • Legal defensibility: Reduce the risk of disputes or challenges from tenants, leaseholders, or insurers.
  • Practical Advice for Landlords and Solicitors
  • Engage a surveyor with proven experience in fire safety and external wall systems.
  • Use the assessment to prioritise works, manage budgets, and inform leaseholder communications.
  • Keep detailed records—these can be critical for future valuations, lending, or legal purposes.

The royal Institute of Chartered Surveyors (which we are a member of) also shared this helpful and thorough list of FAQs on cladding and EWS, in the wake of the Grenfell tower tragedy.

Call us today to discuss your assessment needs on 020 3176 0029