Cladding remediation – building warrant applications: outline approach to verification

Outline approach to the verification of cladding remediation building warrant applications

We produced this guidance to support those parties involved in cladding remediation works. It should be read together with Local Authority Building Standards Scotland Information Paper 43, Guidance on the verification of cladding remediation building warrant applications.  

This is only general guidance and applicants and verifiers should determine the particular circumstances of any building with the building standards.

The Building (Scotland) Amendment Regulations 2022 in relation to buildings undergoing cladding remediation works

The Building (Scotland) Amendment Regulations 2022 introduced amendments to the Building (Scotland) Regulations 2004 which set out mandatory functional standards for buildings.

The amendments applied from 1 June 2022 and introduced a ban on the use of combustible cladding materials to all relevant buildings over 11 metres in height. 

A relevant building includes:

• dwellings
• buildings used as places of assembly, recreation or entertainment
• hospitals, residential care buildings and sheltered housing and shared multi-occupancy residential buildings

The restrictions on the use of combustible materials in an external wall cladding system are set out in Regulation 8 of the Building (Scotland) Regulations 2004, as amended by Regulation 3 of the Building (Scotland) Amendment Regulations 2022.

The requirement is that building work on such buildings must be carried out so that only building materials which achieve European Classification A1 or A2-s1, d0 become part of an external wall classified in accordance with BS EN 13501-1:2018 entitled “Fire classification of construction products and building elements. Classification using testing data from reaction to fire tests” published by the British Standards Institution. The standard must also be achieved in connection with any material that forms part of a specified attachment (as defined in Regulation 8(6)) unless covered by any relevant exemption. 

Building regulations are not applied retrospectively. Therefore materials which are already part of the external wall, or are existing specified attachments, and which are not being replaced, are not covered by the ban. Where building materials are being replaced, they must meet the requirements of Regulation 8. 

During the remediation process care must be taken to ensure that the building is no less compliant in relation to building regulation requirements after work has taken place than before the work was carried out.

It is for the local authority, in their role as Building Standards Verifier, to assess compliance and the specifics of each project should be discussed with the relevant verifier with responsibility for the area where work is taking place.

Using A2-s1, d0 class materials for cladding replacement

Where replacement of cladding is necessary the materials should meet the requirements of the building regulations. Any new materials used in cladding replacement work that are less than A2-s1, d0 class materials would not be compliant for buildings over 11m in height.

See below for further advice on reusing materials.

Restriction on the use of combustible materials

The restrictions on the use of combustible materials apply to all materials used in the external wall cladding system, including encapsulated insulation materials, other than insulation material being used underground, or up to 300 mm above ground. Regulation 8 applies to all materials used in the external wall cladding system.  

The only circumstance in which insulation materials within a cavity, that do not need to meet the European Classification A1 or A2 standard is when it is fully encapsulated in masonry or concrete where both leaves are at least 75 mm thick and where there are suitable cavity barriers around all openings in the wall and at the top of the wall head. Further guidance is provided at section 2.6.5 of the Building Standards Domestic Technical Handbook 2025.

Components exempted by Regulation 8(4)

The Building Standards Domestic Technical Handbook, which provides guidance as to how to achieve the requirements set out in the regulations makes clear that life safety is the main objective of fire safety. All materials used, whether combustible or not, must meet the appropriate standards of fire resistance in respect of duration.   

In addition to the regulatory requirements in relation to workmanship and material quality, the works must meet the Mandatory Standards set out in the Domestic Technical Handbook which support, amongst other things, the effective compartmentation of fire and smoke. Accordingly the composition of materials used in relation to exempted components must still enable the building to achieve the Mandatory Standards.

Signage

Signage is not considered to form part of an external wall system or specified attachment.

There is a risk of fire spread from specified attachments, including balconies, solar panels and solar shading. Where a building has a storey height of 11m or more above the ground, specified attachments must be constructed of products that achieve European Classification A1 or A2. 

Extendable and retractable solar shading products, including awnings and canopies are not considered to be fixed solar shading attachments, as specified by Regulation 8. Notwithstanding this, for awnings and canopies a risk based approach still needs to be taken to assess the risks of vertical fire spread in accordance with the mandatory standards. Where for instance, awnings/canopies are present on every storey of a building above 11m this would be considered to pose a much greater risk of fire spread.

Designated materials

Products which have been deemed by European Commission decisions to meet Class A2-s1, d0 or A1 can be considered to meet the new requirements.

Limited combustibility materials

Materials used in cladding remediation work must be A1 or A2 class. Materials that are of limited combustibility must not be used.

Windows

Window frames are excluded from Regulation 8. However, spandrel panels and other infill panels are included in Regulation 8. Accordingly, any such panels where they are being replaced, must comply with the regulations.

Building works such as reapplication of sealants or gasket replacement

The ban on the use of combustible materials applies to any materials becoming part of the external wall cladding system or specified attachments of relevant buildings, other than where the material is exempted under Regulation 8(4). 

Accordingly, even when materials are expressly exempted consideration should be given to the material used and how this supports the inhibition of fire spread across the external wall.

The Mandatory Standards in respect of fire spread over the external wall of a building must always be demonstrated.

Cladding systems - carrying out of other work, such as fitting of alarms

If mitigation of fire risk covers work other than cladding replacement then there is no requirement to bring the cladding up to current standards.

A building warrant may be required for other works to the building, such as fitting fire alarms or automatic fire suppression systems.

Reinstalling of components with less than A1 and A2 specification

It is possible that remediation may involve temporarily removing materials and components which are already part of the external wall in order to replace another part of the wall system, such as where a rainscreen is removed to access cavity barriers or insulation beneath. In this situation it is possible to reuse the same component where that can be done without excessive damage.

Cladding components damaged when temporarily removed

Where there is limited damage, no more than 30% of the relevant type of cladding, then the same specification of materials that are being replaced can be used.

Cladding system components replacement

Where the design and specification of the cladding remediation works are limited to certain components then the Building Warrant only requires to cover those works. As stated above any new materials and works must meet the current standards.

Cladding Remediation Programme - building warrant requirements

It is not possible to remove the requirement for a building warrant where the proposed works require one. However, the works that are covered by a building warrant will be informed by the Single Building Assessment findings and options for achieving tolerable risk in the building.