Is building regulations approval always required for a mezzanine floor?
Yes, in all cases. There is no size threshold, use type or building category that exempts a mezzanine floor from building regulations. A mezzanine floor – whether used for storage, offices, production or plant – introduces new structural loads, creates a new occupied or accessible level, and affects the fire safety strategy of the building. All of these are matters governed by building regulations.
Building regulations approval is not the same as planning permission and is not affected by whether planning permission is required. The two are independent processes. A mezzanine that does not need planning permission still requires building regulations approval.
What triggers the building regulations requirement?
The Building Act 1984 and the Building Regulations 2010 apply to building work, which includes the construction of a new structure within an existing building. A mezzanine floor constitutes building work because it:
- Introduces new structural loads to the host building through column bases bearing on the existing floor slab
- Creates a new occupied or accessible level, altering the building’s internal configuration
- Affects fire safety, means of escape and fire compartmentation within the building
- In many cases requires fire protection to the supporting steelwork to achieve a required fire resistance period
- May affect accessibility, ventilation and drainage depending on the intended use
Each of these triggers is independent. A mezzanine used solely for plant storage with no regular occupancy still introduces structural loads and affects the building’s fire strategy – both of which require assessment and approval.
Which approved documents apply to a mezzanine floor?
Building regulations are supported by approved documents that set out how compliance can be achieved. Those most relevant to a mezzanine installation are:
- Approved Document A (Structure) – structural loading, design and the capacity of the existing floor slab to carry column loads
- Approved Document B (Fire Safety) – means of escape, fire detection, fire compartmentation and fire resistance of structural elements
- Approved Document K (Protection from falling, collision and impact) – stair design, balustrade and edge protection heights and guarding
- Approved Document M (Accessibility) – provisions for access and use where the mezzanine is to be occupied
Approved Document B is typically the most significant in terms of design impact. Fire safety requirements – particularly escape routes, travel distances and fire protection to steelwork – shape the structural and architectural specification of most mezzanine installations.
What are the two routes to building regulations approval?
If you’re planning a mezzanine floor, there are two procedural routes to building regulations approval – and understanding the difference matters before your contractor gets started.
The first is a full plans application. Structural calculations, drawings and a specification are submitted to the building control body before work begins. They review the submission and issue a formal approval notice. This is the standard route for mezzanine installations – it gives everyone certainty before construction starts.
The second is a building notice. A shorter notice is submitted before work begins, without full drawings. The building control body inspects the work during and after construction rather than reviewing it upfront. It’s faster to initiate, but it carries more risk – if work doesn’t comply, it can be required to be altered after the fact, with no prior approval to fall back on. It’s less commonly used for mezzanines, which typically require structural calculations regardless.
In both cases, the approval or notice must be in place before work begins. Building control will carry out inspections at defined stages during construction.
The full reference guide covers what a building regulations submission includes, who submits it and what the typical timeline looks like.
There are two procedural routes to building regulations approval for a mezzanine floor:
- Full plans application: structural calculations, drawings and a specification are submitted to the building control body before work begins. The building control body checks the submission against the relevant approved documents and issues an approval notice. This is the standard route for mezzanine installations and provides certainty before construction starts.
- Building notice: a shorter notice is submitted before work begins, without full drawings. The building control body inspects the work during and after construction. This route is faster to initiate but carries more risk – work can be required to be altered if it does not comply, with no prior approval to rely on. It is less commonly used for mezzanine installations, which typically require structural calculations in any case.
In both cases, approval or notice must be in place before work begins. The building control body will carry out inspections at defined stages during construction.
What does a building regulations submission include?
A full plans submission for a mezzanine floor typically includes:
- Structural calculations demonstrating that the mezzanine structure meets the requirements of Approved Document A, including verification of existing slab capacity at column positions
- Architectural drawings showing floor layout, stair positions, edge protection, escape routes and headroom clearances
- A fire strategy statement or fire engineer’s report addressing means of escape, travel distances, fire detection and fire protection to the structure
- Specification of fire protection to steelwork where required, including the fire resistance period and method of protection
- Accessibility provisions where the mezzanine is to be occupied
The scope of the submission reflects the complexity of the installation. A straightforward storage mezzanine in a large warehouse may require a relatively concise package. An office mezzanine in a building with complex escape constraints will require a more detailed fire strategy and may benefit from early engagement with the building control body.
Who submits the application and who approves it?
The building regulations application is submitted by or on behalf of the party carrying out the work – typically the mezzanine contractor or a structural engineer acting for the client. In practice, most specialist mezzanine contractors manage the building regulations submission as part of the design and installation process.
Approval is granted by a building control body. There are two types:
- Local authority building control (LABC) – the building control service of the local authority for the area where the building is located
- Registered Building Control Approvers (previously known as approved inspectors) – private building control bodies that operate to the same technical standards as local authority building control
Either can be appointed. The choice is made by the client or contractor. Both operate to the same approved documents and technical standards; neither is more or less stringent than the other.
What happens if work starts without approval?
Installing a mezzanine floor without building regulations approval is a criminal offence under section 35 of the Building Act 1984. The local authority has the power to require the structure to be altered or removed if it does not comply, and can prosecute the person carrying out the work.
In practical terms, work carried out without approval also creates difficulties when the building is sold or the lease is assigned. A buyer’s solicitors will require evidence of building regulations compliance, and a retrospective regularisation application – where one is available – carries additional cost and uncertainty.
Approval must be in place before work begins. Starting on site before a full plans approval is issued, or before a building notice has been properly submitted, is not compliant.
