The United Kingdom Building Regulations are statutory instruments that seek to ensure that the policies set out in the relevant legislation are carried out. They’re in place to make sure that buildings are safe, energy-efficient, and accessible and that they provide adequate facilities for people in and around the buildings. They apply to most new buildings and many alterations of existing buildings in England and Wales, whether domestic, commercial, or industrial.

Part L of Building Regulations

In particular, when considering the effect of these regulations on external wall insulation, we should look at Part L, which focuses on the conservation of fuel and power. This part is split into two sections: L1 is concerned with dwellings and L2 with all other buildings. They have been updated several times, with the most recent versions at the time of my knowledge cutoff in 2021 being L1A (new dwellings) and L2A (new buildings other than dwellings).

When applying external wall insulation, building owners must ensure that the U-value (a measure of heat loss) of the wall does not exceed the maximum allowable according to these regulations. The exact U-value will depend on the specific requirements in the current version of Part L. In general, adding insulation will improve the U-value (i.e., reduce heat loss), so external wall insulation can help buildings comply with these regulations.

However, it’s important to note that the work should also comply with other parts of the Building Regulations. For example:

• Structure – Part A: The additional weight of the insulation material should not compromise the structural integrity of the wall.
• Fire Safety – Part B: The insulation material should meet fire safety standards.
• Site preparation and resistance to contaminants and moisture – Part C: The insulation should not create problems with dampness or mould.
• Ventilation – Part F: The insulation should not create issues with ventilation.

The Building Act

Building regulations in the United Kingdom, particularly in England, set standards for the construction and refurbishment of buildings. They are derived from the Building Act 1984 and the Building Regulations 2010, and they ensure minimum standards for the design, construction, and performance of new buildings. Building control bodies, which can be either local authority building control or privately approved inspectors, must approve new buildings to ensure they meet these standards.

These regulations are performance-based; that is, they define outcomes that must be met but do not dictate how these outcomes must be achieved. For instance, a building must meet specific energy efficiency requirements, but it does not have to be fitted with a particular type of insulation or heating system. This approach allows for flexibility in achieving the set objectives.

Building regulations are applied to existing buildings only when they undergo specific changes, such as refurbishment. In the case of external wall insulation, for example, regulations would be relevant when an existing building is being retrofitted. These renovations must also comply with the Building Regulations to ensure they meet safety, structural integrity, fire safety, and energy efficiency requirements, among others.

Anyone carrying out work controlled under these building regulations must secure approval from a building control body. The approval process consists of three stages: notification to the local authority before starting, regulatory inspections during construction, and issuance of a completion or final certificate after the work if it is found satisfactory.

Grenfell Tower and external cladding

In the aftermath of the tragic Grenfell Tower fire in 2017, which resulted in the deaths of 72 people and was linked to non-compliant cladding material on the external walls, a comprehensive review of building regulations and fire safety was initiated. This led to the passage of the Building Safety Act 2022, which introduces stringent rules for the construction, refurbishment, and occupation of high-rise residential buildings. The Act also established a new regulatory body, the Building Safety Regulator (BSR), within the Health and Safety Executive.

The Act addresses explicitly ‘higher-risk’ buildings, defined as structures that are 18 or more metres in height or have seven or more storeys and contain at least two residential units. During the design, construction, and refurbishment phase (starting October 2023), the BSR will oversee the building control approval process for all higher-risk buildings. The buildings will have to pass through three gateway points to ensure that fire safety is considered at all stages of the process.

During the building’s occupation, the Act introduces the role of the ‘accountable person’, typically the building owner or the person in charge of maintenance. This individual is responsible for assessing and managing ‘building safety risks’, registering the building with the BSR, and ensuring compliance with safety regulations.

The Building Safety Act 2022 further streamlines the functioning of private-sector and public-sector building control bodies, replacing privately approved inspectors with ‘building control approvers’, who must register with the BSR. Non-compliance with BSR’s standards could lead to enforcement action, including potential suspension of a local authority’s building control function or revocation of a building control approver’s registration.

Impact of Building Regulations

The Act also strengthens local authorities’ enforcement powers to deal with violations of the building regulations. They can issue stop or compliance notices, and time limits for existing enforcement powers will be extended or removed. The BSR will hold the same powers as local authorities. The implications of these updated regulations for external wall insulation are significant, particularly in terms of fire safety and energy efficiency. The insulation materials and methods used must meet the stringent standards set out in the regulations. It’s now more critical than ever to ensure full compliance with the regulations during the installation process, as the penalties for non-compliance have been significantly enhanced.