ACM cladding in Scotland: questions and answers

Grenfell fire and ACM cladding

What caused the Grenfell fire?

Information released to date suggests that the fire was started by a faulty fridge however the cause of the fire is still being fully investigated.

Why is there a focus on the Grenfell Tower cladding?

It is believed that the external cladding system installed as part of a recent refurbishment of Grenfell Tower contributed to the rapid spread of fire.

What type of cladding was installed in Grenfell Tower?

Aluminium Composite Material (ACM) type cladding.

What is ACM cladding?

ACM is a generic name (there are a number of products on the market) for a type of flat panel that consists of two thin aluminium sheets (0.5mm) held together with a core filler, typically between 3 and 7mm thick. The panels are much lighter than solid aluminium panels of the same dimensions and, from a weather protection perspective, meet the same levels of performance. The panels can have a painted or metallic finish (e.g. copper or zinc effects).

Are there different types of core filler in ACM cladding?

There are three basic types of core filler materials, which have different attributes, including reaction to fire.

What are the three types of core filler?

The three types of filler material are:

• Unmodified polyethylene (PE) – little or no inherent resistance to fire
• Fire retardant polyethylene (FR) - limited resistance to fire
• Limited combustibility mineral (A2 classification when tested in accordance with European Standards)

Scottish building regulations and high rise domestic tower block cladding

Can the same type of cladding found on Grenfell be used in domestic tower blocks in Scotland.

No, Building Standards systems and regulations for high rise (over 18m) domestic properties in Scotland means the type of product used on Grenfell Tower should not be used in the cladding systems.

What do Scottish building regulations say about the use of cladding on high rise domestic tower blocks?

Since 2005 Scottish building regulations have stated that cladding and insulation on high rise domestic buildings should either be made of non-combustible materials or the whole cladding system has been the subject of a stringent fire test. From 2005 these regulations applied to new high rise domestic buildings or re-cladding work to existing high rise domestic buildings.

The Building Standards Technical Handbooks can be downloaded at http://www.gov.scot/Topics/Built-Environment/Building/Building-standards/techbooks/techhandbooks/th2016domfire

External cladding on high rise domestic buildings built or altered before 2005 had to meet a Class 0 classification which was the most demanding anti-flame spread classification at that time.

If building standards in Scotland mean this type of cladding shouldn't be used then why are we concerned in Scotland?

While we continue to be confident that we have stringent building and fire safety regulations which contribute to keeping people safe, we will not be complacent. Scottish Government is acting to reassure residents of high rise domestic buildings that the type of cladding identified in Grenfell is not used and to ensure robust fire safety in the light of the Grenfell Tower tragedy.

How do Scottish regulations on domestic tower blocks differ from those in England?

In essence the building regulations for cladding systems for domestic tower blocks are similar between Scotland and England. Both sets of regulations require the cladding to either be formed of non-combustible material or meet stringent fire testing. Guidance to the Building Standards system in Scotland does not recognised the use of "comparative desk top studies" to assess the fire performance of the cladding system.

Checks in Scotland for ACM cladding in high rise tower blocks (Updated 23 October 2018)

Are we sure the cladding systems in social housing high rise tower blocks in Scotland are not the same as that used in Grenfell Tower?

Yes, all 32 Scottish local authorities reported that no local authority or social high rise domestic properties in Scotland have been extensively clad in ACM. 

What about the cladding systems in private high rise domestic tower blocks in Scotland – are these also being checked?

Yes, all local authorities completed checks on private sector properties. 31 local authorities have reported to that no privately owned high rise domestic properties have ACM in their cladding system. Glasgow City Council has confirmed a private high rise development in Glasgow has extensive ACM cladding. Interim mitigation measures are in place and the cladding is scheduled to be replaced.

What if my building has small amounts of ACM?

The UK Government in consultation with their Independent Expert Advisory Panel published revised guidance for building owners on 28 September 2018 covering high rise domestic buildings that have small amounts of ACM cladding. This guidance note provides advice to building owners, their professional advisers and fire and rescue services when considering whether it is safe to leave small or partial amounts of Aluminium Composite Material (ACM) cladding on a building.

Does guidance from the UK Government apply in Scotland?

Whilst the Ministry of Housing, Communities and Local Government guidance applies to England, the same general principles of the guidance should be applied in Scotland. The legislation applicable in Scotland includes the Housing (Scotland) Act 2006, The Fire Safety (Scotland) Regulations 2006, The Building (Scotland) Regulations 2004 and the supporting guidance contained in the Technical Handbooks.

What about small amounts of other combustible materials on my building?

The UK Government in consultation with their Independent Expert Advisory Panel published guidance for building owners on 17 October 2018 covering spandrel panels, window panels and infill panels on external walls of high rise domestic buildings. This guidance note provides advice to building owners, their professional advisers, and fire and rescue services. 

What about other types of cladding – how do we know these are safe?

Scottish building regulations state that cladding and insulation on high rise domestic buildings since 1 May 2005, and cladding and insulation added to existing high rise domestic buildings since 1 May 2005, should be made of non-combustible materials or a cladding system that has met stringent fire tests. External cladding on high rise domestic buildings built before 2005 had to meet a Class 0 classification which was the most demanding anti-flame spread classification at that time.

The UK Government in consultation with their Independent Expert Advisory Panel issued a guidance note on 17 October 2018 covering external wall systems that do not incorporate Aluminium Composite Material. This guidance note provides advice to building owners, their professional advisers, and may also be used by fire and rescue services.

Schools and ACM cladding

What about high rise schools in Scotland do they have the same type of cladding as that used in Grenfell?

No Scottish local-authority owned school buildings above 18 metres have the type of cladding reported to have been used on the Grenfell tower – aluminium composite material (ACM).

What about private schools, are they being checked too?

Scottish Government is also working with independent schools and have asked that they check their estate for ACM cladding systems.

What about low rise in schools in Scotland are they being checked for ACM cladding?

Yes, the Deputy First Minister and Cabinet Secretary for Education and Skills formally wrote to local authorities to investigate whether there is ACM cladding systems on any low rise school buildings.

Was ACM found in any low rise schools?

From the returns for low rise school buildings, ACM was identified on 30 buildings across 12 local authorities which represents 1% of the schools estate. The returns identified that different types of ACM have been used and the extent of coverage on individual buildings varies significantly.

What if anything is being done about ACM found in low rise school buildings?

The use of ACM on low rise school buildings is appropriate where the cladding system has been installed correctly in accordance with building regulations. However, local authorities are responsible for ensuring the safety of school buildings in their areas and checks are being undertaken by local authorities and the Scottish Fire and Rescue Service on these buildings.

On 1st August John Swinney , Deputy First Minister and Cabinet Secretary for Education and Skills issued a letter to all Education Directors and Chief Executives advising that as part of these checks, it is also important for a fire risk assessment to be carried out and that any necessary and appropriate interim fire safety measures put in place. The letter advised that local authorities should seek and follow professional advice on next steps depending on their own particular circumstances and what, if anything, these further checks and assessments show. In view of the need to ensure of the health, safety and wellbeing of children, young people, teachers and staff, he asked local authorities to confirm the following:

• that they are content that their school buildings are considered safe in terms of building regulations and fire safety

• where they have identified any action(s) to be carried out, what action(s) they are taking and the timescales involved

Did all authorities confirm that there schools were safe?

All 32 local authorities have responded and Scottish Government are reassured that local authorities have fully investigated and are taking any and all necessary action to ensure the fire safety of their school estate.

Why is ACM allowed on low rise properties including schools in Scotland?

Low rise buildings are generally less at risk of fire due to cladding issues as the fire service can more easily deal with a fire below 18 m. For that reason, building standards guidance allows limited combustible materials to be used in low rise buildings subject to certain conditions. For example timber is used on many new houses as an external cladding material. If a system of ACM cladding is identified on any of Scotland's buildings where users may be at risk we are working with local authorities and property owners to ensure that the appropriate safety regulations have been followed.

Universities, colleges and student accommodation and ACM cladding

What about high rise universities and colleges in Scotland do they have the same type of cladding as that used in Grenfell?

The Scottish Government is working with the Scottish Funding Council to seek assurances from Universities Scotland and Colleges Scotland that all colleges and universities are taking forward an assessment of their estate.

Will this assessment include student accommodation?

Yes, this assessment includes purpose built student accommodation including that provided by private organisations.

Was the same cladding used in Grenfell found at student accommodation at Napier University Edinburgh?

We are aware that Napier University identified cladding in one of its student residences that is thought to be similar to the cladding used in Grenfell. The university has taken steps to replace this cladding as a precaution and has reassured students that additional robust fire safety measures – including sprinklers – are in place.

If regulations in Scotland state this type of cladding shouldn't be used, why then has it been found at Napier?

We await further information from City of Edinburgh Council and Napier University to establish exactly what material was found and, if non-compliant with building regulations, how this has come to be been used on the high rise student accommodation. Additionally, we are keen to understand the background to the installation of this cladding during construction.

Hospitals and ACM cladding

What about hospitals in Scotland, do they use the same cladding as Grenfell?

All Health Boards in Scotland have confirmed that none of their buildings above 18m use exactly the same cladding type reported to have been used on Grenfell Tower. However, rigorous further checks have been commissioned to establish the use of any ACM panels, confirmation of combustibility and compliance with building regulations.

What have these further checks found?

Checks so far have found a type of Aluminium Composite Material on parts of the Queen Elizabeth University Hospital of a similar type to, but not the same as, the material used at Grenfell Tower. As a precaution these panels are being removed by the health board.

Low rise domestic properties (below 18m) and use of ACM

Is ACM allowed on low rise domestic buildings in Scotland?

Yes, in some controlled circumstances specified by Scottish building regulations, some ACM products can be used as part of the cladding systems if correctly installed. Our building regulations specify the relevant technical requirements applicable in each case.

Why is ACM allowed on low rise domestic properties in Scotland?

Low rise buildings are treated differently because the fire service can more easily deal with a fire below 18 m. For that reason, building standards guidance allows limited amount of combustible materials to be used in low rise buildings subject to certain conditions. For example timber is used on many new houses as an external cladding material.

Building standards on non-domestic buildings

We know ACM is not allowed on high rise domestic properties in Scotland but is it allowed on non-domestic high rise buildings?

Yes, in some controlled circumstances specified by Scottish building regulations, some ACM products can be used as part of the cladding systems if correctly installed. Our building regulations specify the relevant technical requirements applicable in each case. http://www.gov.scot/Topics/Built-Environment/Building/Building-standards/techbooks/techhandbooks/th2017nondomcomp

Do building standards differ for domestic and non-domestic in Scotland?

Yes, exact standards and regulations will depend on the category and use of the building.

Does this mean public buildings where people sleep such as hospitals do not have the same high standard of building regulation and safety?

No, all building regulations in Scotland are in place to ensure adequate and appropriate standards and safety regulations are in place for all categories of buildings and their particular use.

Why and how do they differ?

In high risk buildings such as hospitals, shopping centres, elderly care homes etc. there are many additional fire protection measures such as enhanced fire alarm systems, sprinklers and enhanced means of escape provision as well as a requirement to undertake regular fire risk assessments.

Further work in Scotland in relation to building and fire safety

What more is being done to ensure building and fire safety in Scotland?

In light of the Grenfell tragedy a Ministerial Working Group has been convened to oversee a review of building and fire safety regulatory frameworks, and any other relevant matters, in order to help ensure that people are safe in Scotland's buildings. The group will make any recommendations for improvement as required. Details of the groups work plan can be found here.

What will the Ministerial Group be doing?

The initial focus will be on high rise domestic buildings, however the Group will also consider other buildings including housing, NHS estate, schools and prisons. The Group will identify and take forward immediate actions in order to provide appropriate reassurance to residents and communities about their safety. In addition, it will identify medium to long-term actions to be taken forward, which will include fire and safety advice and the adequacy of current fire and building regulatory frameworks. The Group will ensure Parliament is updated and respond to any requests as appropriate.

Will the Ministerial Group in Scotland be in touch with the UK Government about what they are doing following Grenfell?

Yes, the Scottish Government will continue to work with the UK Government and other devolved administrations, and will take technical advice as required in order to inform its considerations.

What work has the Ministerial Group done so far?

Details of the work of the Ministerial Group will be regularly updated and can be found here.

Testing of cladding and cladding systems

What tests have been carried out on cladding since Grenfell?

In the immediate days after the fire the UK Government determined that the properties of ACM panels on high rise domestic buildings needed to be clarified. Building Research Establishment (BRE) were instructed to carry out preliminary small scale testing on cladding samples taken from high rise domestic buildings to determine the extent of combustible material present in existing cladding systems.

What were these preliminary tests and what did they show?

Testing was carried out by removing small samples of ACM cladding taken from high rise domestic buildings. These tests were checking whether the filler material was of 'limited combustibility'. All elements being of limited combustibility is one way to meet English building standards. Using a calorimeter - apparatus for measuring heat – the tests found that all samples submitted were combustible and therefore would not meet English building standards.

Why were further large scale tests carried out by the UK Government?

The UK Government set up an Independent Expert Advisory Panel to advise on immediate measures that should be put in place to help make buildings safe. The Panel determined that further full scale testing should be carried out ensure that whole systems i.e. cladding, insulation, support rails, etc together can adequately resist the spread of fire. This is another way to meet both English and Scottish building regulations.

What did these further large scale tests consists of?

These tests were looking at cladding systems and the various combination of constituent parts most likely to be found in high rise domestic buildings. The tests, were carried out to BS 8414 Part 1: 2015 + A1:2017, in conjunction with BR 135.

What is BS 8414 and BR 135?

BS 8414 is a British standard test method that measures the fire performance of external cladding systems. BR 135 sets out principles, design methodologies and fire spread performance characteristics for non-loadbearing cladding systems.

How many and what kind of tests have been carried out?

UK government in conjunction with BRE completed the test programme of 7 full scale fire tests on 16 August. Published fire test reports can be accessed here.

The first test consisted of a cladding system that exactly replicated that used on Grenfell Tower. The cladding system consisted of aluminium cladding rails with PIR insulation between, vertical cavity barriers, horizontal cavity barriers with an intumescent face, vented cavity and PE ACM rainscreen cladding panels. To maintain as much relevancy to Grenfell as possible, the cladding panels and insulation used in this test were the same type and came from the same manufacturers as those used on Grenfell Tower. This test failed to meet BS 8414 Part 1: 2015 + A1:2017, in conjunction with BR 135.

What were the results of the other tests?

In addition to the first test, test 2 (PE ACM and stone wool insulation) and test 3 (FR ACM and PIR insulation) also failed to meet the criteria set out in BR135. Test 4 (FR ACM and stone wool insulation) and test 5 (A2 ACM and PIR insulation) both satisfied the criteria set out in BR 135 and as such would comply with the requirements of building regulations.

The UK Government have yet to release the results of test 6 (A2 ACM and stone wool insulation) and 7 (FR ACM and phenolic foam insulation) however it is expected they will be available here in due course.

What does Scotland's building regulations say about BS 8414 testing?

Building regulations state that cladding systems on high rise domestic buildings should either be constructed of non-combustible materials or tested to BS 8414, in conjunction with BR 135. Therefore the cladding systems subject to UK tests that have failed would not be approved for use on high rise domestic buildings in Scotland.

Why are Scotland not conducting their own cladding fire tests?

Scottish Government is taking an evidence led approach. The UK Government has confirmed laboratory testing of ACM cladding panels is open to all the devolved administrations. However as no ACM cladding has been reported in Scotland no tests have been required.

Scottish building regulations state that cladding on high rise domestic buildings built since 2005, and cladding added to existing high rise domestic buildings since 2005, should be made of non-combustible materials or a cladding system that has met BS 8414 fire tests. Building Standards systems and regulations for high rise (over 18m) domestic properties in Scotland means the type of ACM product used on Grenfell Tower and currently being tested by the UK government should not be used in the cladding systems in Scotland.

So how were checks carried out in Scotland to establish if ACM has been used?

All local authorities keep records of their buildings and the type of material used to build them which has enabled them to determine whether ACM cladding has been used. Physical inspections are carried out where any issues were identified or further reassurance was sought. A number of authorities and property owners have been pro-active in their approach to checking their properties.

What action will be taken if ACM panels are found?

It is the responsibility of local authorities or the property owner to determine the appropriate course of action in consultation with the Scottish Fire and Rescue Service. However, the specific type of ACM used on the Grenfell Tower should not be used in the cladding system of any high-rise domestic property in Scotland. Our checks so far confirm that this is the case and no high rise social domestic tower blocks have ACM.

If a building owner is unsure about the type of cladding used, what can they do?

All local authorities keep records of buildings subject to a building warrant and the type of material used to build them. Owners could in the first instance check these records. Additionally the UK Government has set up testing facilities for landlords and building owners who have doubt over the cladding material used on their building. These facilities are available to anyone in the UK.

Additional measures for fire safety

What additional measures if any are being taken in Scotland to ensure the fire safety of tower block residents?

The Scottish Fire and Rescue Service undertake fire safety and incident planning visits to high rises and undertakes regular visits to all high rise buildings – totalling more than 3,000 visits per year. An additional 700 operational assurance visits have been carried out since the Grenfell Tower fire and more than 900 additional home fire safety visits to residents in high-rise buildings. At present, the Service is giving priority to high rise residents who ask for a Home Fire Safety Visit. Additionally fire crews make quarterly visits to all high rise buildings to ensure local fire-fighters are familiar with their layout, facilities and access arrangements. Multi-storey fire safety advice is available on the Scottish Fire & Rescue Service website and fire fighters are proactively promoting safety messages. http://www.firescotland.gov.uk/your-safety/for-householders/multi-storey-flats.aspx

I have heard fire doors have failed UK Government fire tests – what advice has been issued by the Scottish Government?

Guidance has been published on the Scottish Government website. The guidance note is for building owners and specifically relates to composite fire doors. Further information can also be found in published letters to all Scottish Building Standards Managers. UK Government fire door tests are ongoing and the sector is working with national trading standards on remediation.   

What about sprinklers – do all high rise domestic tower blocks have sprinklers?

Since 2005, building regulations require all new high rise domestic buildings in Scotland to be fitted with sprinklers. The provision of sprinklers within existing high rise domestic buildings is not compulsory, however a number of councils provide these when undertaking major refurbishment work such as improving the thermal insulation of external walls. Sprinklers are only one of a range of risk reduction measures and the Scottish Fire & Rescue Service raises awareness of fire risk in the home and encourages people to take steps to make their homes safe.

Will the Ministerial group be looking at actions to fit sprinklers in high rise tower blocks built before 2005?

While Scottish Ministers continue to be confident that there are stringent building and fire safety regulations which contribute to keeping people safe, following the tragic events at Grenfell Tower it is imperative that a thorough and critical review of regulations is undertaken. The Ministerial Working Group overseeing this process will consider all relevant measures to ensure the safety of residents in high-rise domestic buildings. This includes a review of evidence on fire suppression systems, such as sprinklers and other preventative measures. At the Ministerial group held on 9th August 2017 agreement was reached that further research will be carried out to evaluate specific risks in high rise domestic buildings, consider the most vulnerable groups and recognise advances in technology. The first aspect of this work will be to commission a detailed inventory of the design of all high domestic buildings in Scotland to provide an evidence base to understand the range of buildings and their features, this information would be considered by the Ministerial working group.

What about smoke alarms – are there plans to make them compulsory in every home?

Currently smoke and fire alarm standards differ for new buildings, social housing, private rented housing, and older owner occupied housing reflecting assessments of risk and best practice at the point of setting standards. Standards in new build and private rented sector properties have the most stringent requirements. Agreement was reached at the third meeting of the Ministerial Working Group on 13 July for a consultation to take place in the autumn on common standards for fire and smoke alarms in housing. In addition the Ministerial Working Group has agreed to examine what other proactive preventative measures we can take to ensure that our buildings are as safe as practical.