Publication - Consultation analysis

Multi‑storey residential buildings - fire risk posed by external wall systems: consultation analysis

Published: 11 Feb 2021

An independent analysis of consultation responses to the Draft Scottish Advice Note (SAN): Determining the fire risk posed by external wall systems in existing multi-storey residential buildings.

Multi‑storey residential buildings - fire risk posed by external wall systems: consultation analysis
9. Guidance on Fire Safety Risk Assessments

9. Guidance on Fire Safety Risk Assessments

Question 7. Does the guidance clearly explain the difference between a fire safety risk assessment which considers external wall systems and one that requires an intrusive external wall appraisal?

Overview of Responses to Question 7

Table 16: Does the guidance clearly explain the difference between a fire safety risk assessment which considers external wall systems and one that requires an intrusive external wall appraisal?
  Yes No
  Number % Number %
Individual 7 100% 0 0%
Organisation 9 56% 7 44%
Fire Safety / Engineering / Consultants 3 75% 1 25%
Misc Construction 1 33% 2 67%
Finance and Insurance 0 0% 2 100%
Housing and Property Management 1 50% 1 50%
Local Government 2 100% 0 0%
Residents and Tenants Groups 2 100% 0 0%
Further and Higher Education 0 0% 1 100%
Total 16 70% 7 30%

N=23

9.1 A majority of consultation respondents reported that the guidance clearly explained the difference between a fire safety risk assessment which considers external wall systems and one that requires an intrusive external wall appraisal (16, 70%), Table 16. Organisation responses were much more mixed than those from individuals.

9.2 Few of these respondents provided further qualitative feedback to Question 7.

9.3 Among those respondents that agreed the guidance clearly explained the difference between a fire safety risk assessment which considers external wall systems and one that requires an intrusive external wall appraisal, a few raised points regarding the need for clearer definitions of terms used or concerns with language used in that section of the Draft SAN. The points raised are reflected below.

9.4 Ravelston Terrace Cladding Working Group noted that the advice note should define what is meant by the term "acceptable level of risk" in the context of the following statement within the guidance: "a key principle of fire safety risk assessment is to take steps which are reasonably practicable to reduce the risk to life from fire to an acceptable level".

9.5 Linked to the above point was a suggestion from the Fire Sector Federation to rephrase the above statement from the advice note to reflect the fact that "the fire safety risk assessment is to consider what steps have been taken rather than to take steps itself. The assessment could then lead to steps to mitigate any identified risks as part of the overall process". It suggested the following rewording: "A key principle of fire safety risk assessment is to consider what steps have been taken and whether they reduce the risk to life from fire to an acceptable level."

9.6 A wider point raised by both Ravelston Terrace Cladding Working Group and an Individual respondent[4] was that in most cases an intrusive external wall appraisal would likely be required, including to satisfy mortgage lenders, given the challenges business owners/managers might face in obtaining building plans and/or that building records might provide insufficient detail.

9.7 Ravelston Terrace Cladding Working Group went further to suggest that the Final SAN could make it clear that there is an expectation that relevant bodies would make building plans/records and associated documentation available and outline the implications of not doing so. This is reflected in the organisation's quote below.

"It would be very helpful if the Advice Note made it very clear that local authorities, architects, engineers and developers should all be expected to offer copies of all plans and documents to flat owners, free of charge and that this expectation is supported by all relevant professional bodies. Where architects, developers and or engineers refuse to co-operate, it should be made very clear that local authorities will reject all future proposals by that architect, developer or engineer or any connected company. This is a national scandal and the Government and local authorities should use all means available to them to encourage positive engagement by those who refuse to provide supporting documentation and particularly those that are found to be associated with a defective building.

If the local authority does not secure cooperation from the initial offending agency then the non-cooperation by that local authority should extend to any other agency that is associated with the original agency that is refusing or unable to release plans or conduct remediation. That association may be through common directors, common controlling shareholding or any other connection as defined in the legal definition of Connected Companies or Connected Persons".

Ravelston Terrace Cladding Working Group

9.8 Almost one-third of consultation respondents (all organisations) felt that the guidance did not clearly explain the difference between a fire safety risk assessment which considers external wall systems and one that requires an intrusive external wall appraisal (seven, 30%), Table 16.

9.9 These respondents similarly raised concerns with this section of the Draft SAN and felt it was limited, unclear in parts and/or potential misleading.

9.10 Rockwool Ltd held the view that the language used in Section 1.7 of the Draft SAN was unclear, potentially misleading and could cause confusion, as reflected below.

"Overall, we are concerned that this advice note creates confusion over which materials and combinations are safe to use and how to identify them… We are also concerned that the advice note appears in several places to downplay the risks of failure to follow regulations….This does not sufficiently communicate the importance of compliance and consequently does not support assessors to determine where buildings do or do not require an intrusive external wall appraisal".

Rockwool Ltd

9.11 UK Finance also requested greater clarity regarding the level of information and physical inspection necessary/expected to determine the safety of a building, as reflected in the quote below

"If a review of documentation is considered sufficient to identify if an external wall system is considered a risk or not, how will this identify the buildings where materials have been substituted, i.e. fire rated panels for non-fire rated panels, non-combustible insulation for combustible insulation or if cavity barrier have been appropriately installed? Much of this is not visible from a non-invasive inspection or review of the drawings".

UK Finance

9.12 Linked to the point above, ARUP suggested that the advice note could more clearly:

  • Define the methodology of the different types of assessment (i.e. existing documentation only, physical evidence of install components); and
  • Articulate how the Practical Fire Safety Guidance aligns with information in the Draft SAN (and linked to this, raised a question regarding whether the Practical Fire Safety Guidance would require to be updated to include external fire spread).

9.13 It was further noted by ARUP that information on a fire safety risk assessment within the Draft SAN was considered limited (e.g. does not mention the five-step method, what does low risk look like for a high rise building), and that typical guidance used for risk assessment is PAS 79 (specifically excludes the external envelope of a building and there is currently no published guidance on how a fire risk assessor can assess the potential for fire spread on external walls).

9.14 ARUP also highlighted an example of a free tool that is available to prioritise risk assessment of buildings, as noted below:

"This tool is a risk assessment methodology to assist global authorities and building portfolio owners to assess the risks and prioritise inspection/ remediation efforts for the high-rise building inventory in their jurisdiction with exterior wall assemblies containing combustible components. The methodology is qualitative rather than quantitative and follows internationally recognised risk assessment approaches. The method does not recommend specific mitigation measures, but rather prioritises the need for mitigation based on risk factors and provides suggestions for possible mitigation to be assessed on a project by project basis".

ARUP

9.15 As noted above in Section 9.6, Building Societies Association also pointed to conversations it has had with fire engineers which indicated that "as-built drawings and other documentation are often unreliable"…. an intrusive appraisal is often required".

9.16 Wider points noted in the consultation feedback include:

  • Homes for Scotland suggested that the guidance could benefit from more use of visualisations (e.g. process maps) to highlight trigger points at which intrusive external wall appraisals would be required; and
  • UK Finance felt that the guidance implied that the FRA would be able to cover the EWS appraisals. They, however, went on to comment that the skillsets required for each were in their opinion different, and that the individual completing the FRA might not have the necessary skills or qualifications to comment on the external wall system and to advise which cases should be referred for specialist checks.

Question 8: Is the guidance clear on when a fire safety risk assessment may need to be informed by an intrusive external wall appraisal?

Overview of Responses to Question 8

Table 17: Is the guidance clear on when a fire safety risk assessment may need to be informed by an intrusive external wall appraisal?
  Yes No
  Number % Number %
Individual 6 86% 1 14%
Organisation 8 50% 8 50%
Fire Safety / Engineering / Consultants 2 50% 2 50%
Misc Construction 1 33% 2 67%
Finance and Insurance 2 67% 1 33%
Housing and Property Management 1 50% 1 50%
Local Government 2 100% 0 0%
Residents and Tenants Groups 0 0% 1 100%
Further and Higher Education 0 0% 1 100%
Total 14 61% 9 39%

N=23

9.17 Similar to Question 7, consultation responses were also more mixed for Question 8, especially among organisations.

9.18 A majority, however, reported that the guidance was clear on when a fire safety risk assessment may need to be informed by an intrusive external wall appraisal (14, 61%), Table 17. This was somewhat higher for individuals than it was for organisations.

9.19 Only a few wider comments were provided by these respondents.

9.20 An Organisation and an Individual respondent noted earlier comments regarding situations where there was "a degree of uncertainty" or "an element of doubt" – and that the default position was clear that there would therefore require to an intrusive external wall appraisal. The Individual respondent went onto add that this would be the likely scenario in most cases given issues at Question 7 regarding access to, or level of detail within, building plans and records.

9.21 This point was further reflected on by Kingspan who noted that the guidance could lead to a large number of projects defaulting to the more intrusive methods due to a lack of experience or competence in the sector.

"It is our understanding that historically, most fire risk assessments would not have included a review of the external wall system. The FIA noted in guidance published in May 2020 that they dispute that it has ever been the responsibility of Fire Risk Assessment to address external cladding systems. All published industry guidance to date has not referenced external walls as part of an assessment, and no standard methodology exists for carrying out an assessment of external cladding systems".

Kingspan

9.22 Kingspan and an Individual respondent raised further points around competent fire risk assessors as considered below.

9.23 The former noted issues for competent fire risk assessors in obtaining the necessary Professional Indemnity cover to allow them to sign off EWS appraisals of this nature "even if the risk profile of the building/cladding is low". The latter asked that the guidance provide further detail on "who a competent fire risk assessor may be" for the avoidance of any doubt or any ambiguity in the wording "could be" in the following sentence in the Draft SAN:

"A suitably competent specialist with appropriate knowledge, skills and experience in construction and fire safety who understands the BR135 performance criteria and the parameters of the BS 8414 fire tests could be a chartered or incorporated fire engineer registered with the UK Engineering Council or a chartered building surveyor".

9.24 This Individual respondent felt that the guidance could clarify whether "this is a legal requirement, if not alternative qualifications/length of experience/ membership of a professional body should be recommended".

9.25 A relatively large proportion of respondents (predominantly organisations) felt that the guidance was not clear regarding when a fire safety risk assessment may need to be informed by an intrusive external wall appraisal (nine, 39%), Table 17.

9.26 Ravelston Terrace Cladding Working Group noted that the guidance could be clearer on the range of factors that might be sufficient to consider the building safe without the need for an intrusive external wall appraisal. Their view was that "intrusive appraisals should only be required if safe evacuation is clearly conditional on appropriately safe installation of any cladding. If safe evacuation is very likely in all foreseeable circumstances, then there should be no need for further investigation".

9.27 ARUP also noted that it could be challenging for risk assessors to reach a firm conclusion about the external wall build-up without an intrusive inspection. They went on to explain that:

"Fire safety information available post construction is limited, and an adequate record of as built information is commonly not available or inaccurate. There needs to be clear evidence for the external wall build-up for anyone to make a visual only assessment otherwise an intrusive inspection will always be required and in any case, we would always encourage visual verification".

ARUP

9.28 Linked to this point, ARUP noted that the guidance could be improved by setting out how much inspection is sufficient to draw a conclusion on whether an intrusive wall appraisal is required or not. And noted that "external wall systems may appear to be one material but it is only upon intrusive inspection that the build-up is identified as something completely different".

9.29 UK Finance also agreed that greater clarity would be required within the guidance "as there are many unknowns in relation to the types of materials used in the external wall system".

9.30 ARUP further suggested that the wording used in specific elements of the Draft SAN could be more definitive, as follows:

"The phrase used in Section 1.7 point (2) "If there is reason to suspect that cladding might constitute a fire hazard, a detailed appraisal involving intrusive inspection and testing of samples may be recommended." We would note that the phrase "may be recommended" is not definitive enough. A recommendation is either being made, or it is not recommended. If there is no evidence base, then an intrusive inspection is always required".

ARUP

9.31 Both Homes for Scotland and ARUP suggested that the inclusion of visual diagrams could also aid understanding of, and improve, the guidance. The following examples were suggested:

  • a visual process map to highlight clear trigger points that would specify when an intrusive external wall appraisal would be required (e.g. no as built information, re-clad high rise residential building, use of MCMs, infilled balconies, etc);
  • a flowchart of the checklist of questions a risk assessor must work through to determine whether an intrusive external wall appraisal is required or not (i.e. a guiding framework); and
  • a decision-making flowchart to set out when to engage further professionals and what is expected from them.

9.32 Rockwool Ltd and MIMA reiterated previous comments regarding the importance of understanding the cladding's European Classification in order to better understand whether the material is classed as combustible (B-F) under the Euroclass system and that remedial works are urgently undertaken where required. They also felt that the guidance on this issue could be clarified to avoid being misinterpreted – this is reflected in their quote below.

"We also believe there is a risk that bullet 6 in this list could be misinterpreted to mean that a cladding system must have a BS 8414-BR 135 pass even if both the insulation and cladding are non-combustible. This point should be amended to make clear that this criteria pertains to systems using combustible materials only".

Rockwool Ltd

9.33 The Fire Sector Federation also asked for greater clarity within the guidance, namely where it noted the following "where the test report shows an overprovision/unusual positioning of cavity barriers as tested under BS 8414 'Fire performance of external cladding systems'. This is further reflected in the respondent quote below.

"The details highlighted during the CSIC presentations clearly identified that cavity barrier placement relative to thermocouples had an impact on test results. The presentation also indicated that the test layout of cavity barriers would need to be replicated on site. The placement out of the norm in this manner was considered an "over provision".

Therefore, on reviewing the UK Government sponsored tests it would appear to contain what the advice note considers an "over-provision/unusual arrangement of cavity barriers". As indicated in the CSIC presentation the test reports all show the cavity barrier placement relatively close to the thermocouples in the test configuration and not relative to the nominal floor spacing. This was repeated through the test series and is commented on in Section 1.11. There is no mention of this within Section 1.11 of the advice note.

Although we understand that BS 8414 has been updated to reflect this point within Clause 6, this arrangement of cavity barriers would appear to have been a common item. Given that "over provision" or unusual position of cavity barriers is noted in Section 1.7 to consider intrusive assessment more detail on this within the advice note would help bring clarity on this matter".

Fire Sector Federation

9.34 Wider individual points noted include the following, namely that the Draft SAN could:

  • Include advice on how to retrieve archived building information (ARUP);
  • Provide details of how SFRS should be consulted e.g. provide points of contact, links to SFRS website/literature (ARUP);
  • Confirm whether a fire risk assessor is competent to understand matters regarding test houses (e.g. reviewing test reports/certificates, confirming the accreditation of a test house). If this is not the case, it was suggested that testing should not be within the remit of a fire risk assessment but rather be part of an external wall appraisal (i.e. intrusive inspection) to be undertaken by a chartered fire engineer (ARUP); and
  • A suggestion whether Building Standards teams could consider employing their own EWS experts who could sign off new EWS with a certificate that is then referred to by fire risk assessors (USHA Fire (Scotland) Group).

Contact

Email: Colin.hird@gov.scot