Why EWS1 matters in Tower Hamlets
Tower Hamlets has one of the highest concentrations of high-rise residential buildings in London, particularly in the Canary Wharf, Isle of Dogs and Poplar areas. Many of these buildings were constructed between 2000 and 2020 and feature external wall systems that include aluminium composite material (ACM) panels, high-pressure laminate (HPL), rendered insulation systems and other materials that are now subject to scrutiny following the Grenfell Tower tragedy. For flat owners in these buildings, the EWS1 (External Wall System) form has become a critical document for mortgage lending and property transactions.
What is the EWS1 form?
The EWS1 form was introduced by the Royal Institution of Chartered Surveyors (RICS), UK Finance and the Building Societies Association as a standardised way for mortgage lenders to assess the fire risk associated with a building's external wall system. The form is completed by a qualified assessor — typically a chartered surveyor or fire engineer with the appropriate competency — following an assessment of the building's external walls, including cladding, insulation, balconies and any attachments.
The form has five outcomes. A1 means no significant combustible attachments; A2 means an appropriate attachment assessment confirms no remedial works are required; A3 means attachment works may carry potential costs. Under Option B, combustible materials are present: B1 means the assessed risk is sufficiently low that no remedial works are required; B2 means remedial works are required. The lender or valuer decides how the form affects a transaction.
The Tower Hamlets context
Tower Hamlets is disproportionately affected by the cladding and fire safety crisis. The borough contains a large number of buildings over 18 metres in height (the threshold above which the Building Safety Act 2022 imposes the most stringent requirements), many of which were built during the rapid development of Docklands and the surrounding areas. The volume of buildings requiring assessment has created a significant backlog, with many flat owners unable to sell, remortgage or even obtain adequate insurance.
We provide EWS1 assessment services across Tower Hamlets and have detailed experience of the building types and external wall systems commonly found in the borough.
High-rise specific challenges in Tower Hamlets
Complex cladding systems
Many Tower Hamlets high-rises feature multiple cladding types on a single building — a combination of rendered insulation, curtain walling, rain screen panels and balcony systems. Assessing these buildings requires detailed investigation, often including intrusive inspections to determine what lies behind the visible cladding. The complexity increases the time and cost of the EWS1 assessment and the potential scope of any remediation.
Access difficulties
Inspecting the external walls of a 20- or 30-storey building presents significant access challenges. Rope access, mobile elevated work platforms (MEWPs) or cradle systems may be needed to carry out intrusive inspections at height. Access arrangements must be coordinated with the building manager, and traffic management may be required for plant access. These logistics add to the assessment cost and timeline.
Multiple stakeholders
Tower Hamlets' large residential developments often have complex ownership structures involving freeholders, management companies, right-to-manage companies, housing associations and individual leaseholders. Coordinating an EWS1 assessment requires engagement with all relevant parties, agreement on funding and a clear decision-making process. In practice, this stakeholder complexity is one of the main causes of delay in the borough.
Interim fire safety measures
Buildings awaiting remediation often require interim fire safety measures, which may include a waking watch, upgraded alarm systems, fire risk assessment reviews and enhanced management procedures. These measures carry ongoing costs that are typically recovered through the service charge. Understanding the relationship between the EWS1 assessment, interim measures and the remediation programme is essential for flat owners and managing agents.
What to do if your building receives a B2 rating
Understanding the B2 result
A B2 outcome means combustible materials are present and the assessor considers the fire risk sufficiently high that remedial works are required. It does not, by itself, determine immediate danger, urgency, interim measures or occupation. Those decisions require the underlying fire-risk evidence and the responsible dutyholders' assessment; a lender or valuer separately decides the transactional effect.
The remediation pathway
After a B2 outcome, review the assessment that supports the form and the evidence for the required works. If a proportionate FRAEW under PAS 9980 has not already been completed and is appropriate to the building, a competent professional can define that scope. The remediation strategy should follow the building-specific evidence rather than an assumed urgency grade.
Following the FRAEW, a remediation specification is developed, contractors are procured, and the remediation works are carried out. After relevant works, updated external-wall evidence may support a new EWS1 conclusion. The competent signatory records the applicable outcome and each lender or valuer decides whether the evidence is sufficient for its transaction. The entire process from B2 rating to completion of remediation can take 18 months to three years or more, depending on the scale and complexity of the works and the availability of funding.
Funding options
Since 1 September 2025, new applications for government cladding remediation funding for eligible buildings over 11 metres in England, including London, go through the Cladding Safety Scheme (CSS), administered by Homes England. This includes eligible buildings between 11 and 18 metres; height alone does not establish eligibility. The responsible entity or its authorised representative applies, with the scheme-specific building, legal and technical evidence. Check the current CSS guidance and the CSS/BSF transition guidance for the route that applies to an existing application. A separate targeted route is available for eligible buildings under 11 metres; see the current under-11m funding criteria and application window.
Frequently asked questions
What does a B2 EWS1 rating mean for my Tower Hamlets flat?
A B2 outcome means combustible materials are present and the assessor considers the fire risk sufficiently high that remedial works are required. It is not an urgency or occupancy grade. The underlying appraisal informs risk-management decisions, while the lender or valuer decides what evidence it requires for a transaction.
Do I need an EWS1 form to sell my flat in Tower Hamlets?
It depends on the building height. Since January 2023, EWS1 forms should not be required for buildings below 11 metres. For buildings between 11 and 18 metres, lender requirements vary. For buildings over 18 metres (approximately six storeys), most lenders still require an EWS1 form or evidence that the building has been assessed under PAS 9980. In Tower Hamlets, where many residential buildings are high-rise, an EWS1 form is frequently needed for a sale to proceed.
Who pays for the EWS1 assessment in Tower Hamlets?
The cost of the EWS1 assessment is typically borne by the building owner or freeholder, not individual leaseholders. Where the building is managed by a residents' management company, the cost will usually be shared through the service charge. For buildings that qualify for government funding through the Building Safety Fund or Cladding Safety Scheme, the cost of assessment and remediation may be covered. Leaseholders in buildings over 11 metres should not be required to pay more than prescribed caps under the Building Safety Act 2022.
How long does it take to get an EWS1 certificate in Tower Hamlets?
Timescales vary depending on the complexity of the building and the availability of qualified assessors. A straightforward assessment for a building with a simple cladding system may take four to eight weeks from instruction to certificate. Complex high-rise buildings with multiple cladding types may take considerably longer. The shortage of RICS-qualified fire safety assessors means that lead times for initial assessment can be several weeks. We recommend engaging early to avoid delays.
How we can help
EWS1 Form & External Wall Advice
Qualified EWS1 assessments for residential buildings across Tower Hamlets and London.
View ServiceCladding Remediation
End-to-end cladding remediation management from assessment through to completion.
View ServiceRequest a Consultation
Discuss your EWS1 requirements or cladding remediation project with our fire safety team.
Contact UsPrimary sources and further reading
Links checked 18 July 2026. These primary sources provide general context; a competent specialist should confirm how the guidance applies to the building concerned.
Local Level 3 building survey guides
Savas Bulduk
BSc (Hons) MRICS, Director & Chartered Building Surveyor.
Writes on Building surveying, Fire safety and facade, External wall systems, Technical due diligence, Contract administration. See the full team profile.