Highlights
All mezzanine floor installations in the UK require Building Regulations approval. The application covers structural compliance (Approved Document A), fire safety (Approved Document B), staircase and edge protection (Approved Document K), and disabled access where applicable (Approved Document M). Western Industrial submits and manages the Building Regulations application on behalf of every client as a standard part of the service, at no additional charge.
We handle all structural calculations, Building Control correspondence, and provide the completion certificate at handover.
If you are planning to install a mezzanine floor in a commercial or industrial building, understanding the Building Regulations requirements is an essential first step. This guide explains which regulations apply, what they require in practice, when fire protection is and is not needed, what the approval process involves, and when planning permission is required.
Western Industrial, one of the UK’s leading mezzanine floor suppliers, has been managing Building Regulations applications for mezzanine floor projects for over 45 years. We handle the process on behalf of every client, from submitting the application to obtaining sign-off, at no additional charge.
Do you need Building Regulations for mezzanine floors?
Yes, in virtually all cases. The Building Regulations 2010 apply to all building work in England and Wales, and the installation of a mezzanine floor constitutes building work within the meaning of those regulations. Building Regulations approval must be obtained before installation begins, not after.
There is sometimes confusion between Building Regulations approval and planning permission. These are separate requirements. Planning permission relates to the use and external appearance of a building and is, in most cases, not required for an internal mezzanine floor. Building Regulations approval, however, is almost always required and covers the structural safety, fire safety and access requirements of the installation.
Failing to obtain Building Regulations approval is a legal offence. More practically, a mezzanine installed without approval may be required to be removed, may affect your insurance position, and will create problems if you ever sell or lease the property.
For details on UKCA marking, what it means for mezzanine floors and why it matters, see our UKCA marking guide.
Do I need planning permission for a mezzanine floor?
In most cases, no. Mezzanine floors are internal structures that do not alter the external appearance of the building, and as such they are generally treated as permitted development, meaning planning permission is not required. Mezzanine floors under 200m² are typically classified as permitted development in most commercial and industrial settings.
There are exceptions where planning permission may be required:
• If the installation involves any external alterations to the building, such as changes to windows, doors or cladding
• In a listed building, where Listed Building Consent is required for any internal alterations that affect the character of the building
• In some retail environments, where local planning policy may treat the addition of significant new floor area differently
• Where the tenancy agreement or lease contains restrictions on internal alterations that require the landlord’s consent
If there is any uncertainty about whether planning permission is required for your specific project, we advise seeking confirmation from your local planning authority before work begins. Western Industrial can advise on this at the site survey stage.
Which Building Regulations apply to mezzanine floors?
The Building Regulations are set out in a series of Approved Documents, each covering a specific aspect of building work. For mezzanine floor installations, the most relevant are Approved Documents A, B, K and M. Each is discussed in detail below.
Approved Document A | Structure
Approved Document A covers the structural requirements of the mezzanine floor. It requires that the structure is designed to safely withstand all the loads it will be subjected to, both dead loads (the weight of the structure itself) and imposed loads (the weight of people, goods, machinery and equipment placed on the floor).
In practice, this means that the mezzanine must be designed by a structural engineer who will calculate the required load ratings, specify the appropriate beam and column sizes, and confirm that the existing building floor slab is capable of supporting the imposed loads from the mezzanine columns. These calculations are submitted as part of the Building Regulations application.
The load rating must reflect the actual intended use of the mezzanine. An office mezzanine is typically designed to carry around 350 kg per square metre. A storage mezzanine carrying pallet racking may require 480 to 600 kg per square metre. An industrial platform supporting machinery may require significantly more. The structural design must also consider dynamic loads, for example, the movement of pallet trucks or forklifts on the floor.
The structural steelwork must carry UKCA marking in accordance with BS EN 1090-1, confirming that the components have been assessed to the UK’s designated standard for fabricated structural steelwork.
Approved Document B | Fire Safety
Approved Document B governs fire safety requirements and has the most significant practical impact on the cost and specification of a mezzanine floor. The requirements depend on the intended use of the mezzanine and its size relative to the building it is installed in.
For storage mezzanines, fire protection is not required if all of the following conditions are met: the floor is used exclusively for storage or maintenance purposes; it is less than 20 metres in any direction; and it does not exceed 50 per cent of the floor area of the building in which it is located. Only in this specific combination of circumstances can fire protection be omitted from a storage mezzanine. In practice, many storage mezzanines do meet these criteria, but it is always worth confirming the position with a specialist before assuming fire protection is not required.
Fire protection is always required for any mezzanine used as an office, production area, packing area or any other occupied workspace. It is also required for storage mezzanines that are larger than 20 metres in any direction, or that occupy more than half the building’s floor area.
Where fire protection is required, the standard specification involves:
• A one-hour fire-rated ceiling fitted beneath the mezzanine deck, using intumescent boards that expand under heat to protect the steel structure
• Fire-rated casings to the structural columns of the mezzanine
• Designated means of escape – staircases positioned to ensure maximum travel distances to exits are not exceeded
• Clear escape route signage and emergency lighting
• Smoke and heat detection extended to cover the mezzanine where applicable
In some environments, Approved Document B may also require that the mezzanine floor itself provides compartmentation, preventing the spread of fire from one part of the building to another. Your installer and Building Control Inspector will advise on the specific requirements for your project.
Approved Document K | Protection from Falling
Approved Document K covers the requirements for staircases, handrails and edge protection on the mezzanine floor.
The key requirements are:
• Staircases must have consistent riser heights and tread depths, with no more than 16 risers between landings
• Handrails must be provided on at least one side of the staircase, at a height of 900 to 1,000mm
• Adequate headroom must be maintained above the staircase — typically a minimum of 2,000mm
• Edge protection (guardrails) must be provided along all open edges of the mezzanine, to a minimum height of 1,100mm
• Guardrail infill must prevent any opening larger than 100mm – preventing falls through the balustrade
• In industrial environments, toe boards of 100 to 150mm should be provided at loading edges to prevent items being accidentally kicked off the edge
• Pallet gates or safety barriers must be provided at pallet drop edges where goods are loaded or unloaded from the mezzanine
The specification of the staircase and balustrade is one of the most visible elements of a mezzanine floor installation and is one of the areas where there is the most variation in cost and finish between different project types. A standard industrial staircase meets the functional requirements of Approved Document K at the most economical cost.
Feature staircases for office or retail environments are designed to meet the same functional requirements while providing a higher aesthetic standard appropriate for a customer-facing or staff environment.
Approved Document M | Access and Use
Approved Document M covers accessibility requirements for the mezzanine floor. For most warehouse and storage mezzanines used only by employees, the primary requirement is that the staircase meets the dimensional standards set out in Approved Document K and provides safe, practical access for the people who will use it.
Where the mezzanine is used as an office or is accessible to customers or the public, Approved Document M may require additional accessibility provisions. This can include wider staircase dimensions, the provision of a goods or passenger lift to enable wheelchair access to the upper level, and consideration of the Equality Act 2010 requirements for reasonable adjustments to enable access by people with disabilities.
The accessibility requirement is one of the most significant cost variables for commercial mezzanine projects, particularly in retail and public-facing environments where a lift may be required. This should always be explored at the design stage, before budgets are committed.
The Building Regulations approval process
Building Regulations approval for a mezzanine floor is obtained by submitting an application to a Building Control Body (BCB). This is either the Building Control department of your local authority, or a private approved inspector.
Western Industrial uses approved private Building Regulations Inspectors for all our projects. In most cases, this is faster than working through the local authority, and allows the process to run concurrently with the manufacturing and preparation stages of the project.
Work on site can typically begin within 48 hours of the application being submitted.
The application must include:
• Structural drawings and calculations demonstrating that the mezzanine meets the requirements of Approved Document A
• Plans showing the layout of the floor and the escape routes, for assessment against Approved Document B
• Details of the fire protection specification where required
• Access and staircase drawings for assessment against Approved Documents K and M
The Building Control Inspector will review the application, may request additional information, and will carry out an inspection of the completed installation before issuing final sign-off. Western Industrial manages all of this on behalf of the client. The client does not need to deal with the Building Control Body directly.
Approval typically takes around four to six weeks from submission, though this varies depending on the complexity of the project and the workload of the inspector. We factor this into the project programme at the outset.
Building Regulations in leased premises
If you are planning to install a mezzanine floor in a building you lease rather than own, you will typically need both Building Regulations approval and your landlord’s consent before work can begin. Most commercial leases permit internal alterations including mezzanine floor installation, subject to these conditions.
Western Industrial provides all the documentation a landlord is likely to require, including structural drawings, load calculations and the Building Regulations approval certificate. Many landlords are familiar with mezzanine floor installations and, provided the structure is freestanding and removable, are generally supportive.
One practical advantage of a freestanding mezzanine floor for tenants is that it can be dismantled at the end of the tenancy and either relocated or returned to the manufacturer, leaving the premises in their original condition. This is an important consideration when negotiating with a landlord, and worth raising at the outset of any conversation about consent.
PUWER inspections after installation
Once your mezzanine floor is installed and in use, it becomes subject to the Provision and Use of Work Equipment Regulations 1998 (PUWER). These regulations require that work equipment, which includes structures such as mezzanine floors, is maintained in a safe condition and inspected regularly to ensure it remains fit for purpose.
In practice, this means mezzanine floors should be inspected at regular intervals by a competent person, and any defects or deterioration noted and addressed promptly. There is no fixed statutory inspection interval for mezzanine floors, but a periodic inspection regime, typically at least annually, is generally considered appropriate for most commercial and industrial environments.
Western Industrial offers maintenance and inspection services. Contact us if you would like to discuss a programme for your installed floor.
Frequently asked questions about mezzanine floor building regulations
Yes, in virtually all cases. The Building Regulations 2010 apply to mezzanine floor installations as building work. There is no minimum size threshold below which Building Regulations approval is not required. Approval must be obtained before installation begins, not retrospectively.
In most cases, no. Mezzanine floors are internal structures that do not alter the external appearance of the building and are generally treated as permitted development. Exceptions include listed buildings, retail environments where local policy applies, and installations involving external alterations. If uncertain, confirm the position with your local planning authority.
Not always. A storage mezzanine used exclusively for storage or maintenance, less than 20 metres in any direction, and not exceeding 50 per cent of the building’s floor area, can usually remain un-fire rated. Any mezzanine used as an office, production area or packing area must be fire rated, as must any storage floor that exceeds these size thresholds.
Your installer should manage this on your behalf. Western Industrial handles the Building Regulations application as a standard part of every project, using approved Building Regulations Inspectors. We submit the drawings and calculations, handle any queries from the inspector, and obtain sign-off on completion. The client does not need to deal with Building Control directly.
Yes, in most cases. You will need your landlord’s consent as well as Building Regulations approval. Most landlords support mezzanine installations provided they are freestanding, compliant with Building Regulations, and removable at the end of the tenancy. We provide all the documentation your landlord is likely to require, including structural drawings, load calculations and the Building Regulations approval certificate.
PUWER stands for the Provision and Use of Work Equipment Regulations 1998. It requires that work equipment, including mezzanine floors, is maintained in a safe condition and inspected regularly by a competent person. There is no fixed statutory inspection interval, but annual inspection is generally considered appropriate. Western Industrial offers maintenance and inspection services for installed mezzanine floors.
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About Western Industrial
Established in 1979, Western Industrial Group have grown to a dedicated & professional workforce, delivering consistently high quality services across a range of projects, large & small.
From Mezzanine Floors to Warehouse Storage and Racking, Western Industrial Business Interiors design, supply, manage and install, to provide you with a complete office refurbishment package.
We supply and install Mezzanine Floors, Office Partitioning, Air Conditioning, Ventilation & Suspended Ceilings, through to all your Electrical & Mechanical requirements.
