Mezzanine floor glossary
The words you will see on mezzanine quotes, drawings and calculations, explained in a sentence or two.
- Mezzanine floor
- A free-standing intermediate floor built inside a building, usually a bolted steel frame on its own columns, that adds a second level of usable space.
- Rack-supported mezzanine
- A raised floor or walkway carried by the uprights of storage racking or shelving rather than by separate columns.
- Pick module
- A multi-level rack-supported structure with walkways and conveyors, used for high-volume order picking.
- Primary beam
- A main beam spanning between columns, usually a hot-rolled universal beam, that carries the secondary joists.
- Secondary beam (joist)
- A lighter cold-rolled C or Z-section member spanning between primary beams and supporting the deck.
- Universal beam (UB)
- A standard hot-rolled I-section steel beam used for primary beams on heavier mezzanines.
- Square hollow section (SHS)
- A square steel tube commonly used for mezzanine columns.
- Base plate
- The steel plate welded to the foot of a column and fixed to the floor slab with anchors to spread the column load.
- Column grid
- The spacing of columns in each direction. A wider grid gives more clear floor below but needs heavier beams.
- Clear height
- The height available under the mezzanine deck, or between the deck and roof steel above it.
- UDL (uniformly distributed load)
- A load spread evenly over the floor, stated in kilonewtons per square metre (kN/m²).
- Point load
- A concentrated load in one spot, such as a pallet leg, machine foot or column on a slab.
- kN/m²
- Kilonewtons per square metre, the unit for floor loading. 1 kN/m² is roughly 102 kg on every square metre.
- Load notice
- A sign fixed to a mezzanine stating the safe working load it was designed for.
- Deck
- The floor surface of the mezzanine, such as high-density chipboard, steel grating or chequer plate.
- High-density chipboard
- The most common mezzanine deck, usually 38mm thick, laid on steel joists and often with a hard-wearing top surface.
- Steel grating
- An open steel mesh deck that lets light, air and sprinkler water pass through.
- Chequer plate
- Steel plate with a raised diamond pattern for grip, used for heavy-duty decks and platforms.
- Fascia
- The edge trim along the open side of the mezzanine deck, sometimes fire-rated.
- Kick plate
- An upstand at the edge of the deck that stops items and feet sliding off, also called a toe board.
- Pallet gate
- A gate at the mezzanine edge that lets pallets be loaded by forklift; up-and-over types keep a barrier closed between people and the edge at all times.
- Up-and-over gate
- A pallet gate with two linked barriers, so the deck side closes as the loading side opens.
- Balustrade
- The guarding along an edge or stair, which may be mesh, rails, solid panels or glass.
- Approved Document K
- Statutory guidance under the Building Regulations covering stairs, guarding and protection from falling.
- Approved Document B
- Statutory guidance under the Building Regulations covering fire safety, including escape and fire resistance.
- Fire-rated ceiling
- A tested ceiling system fixed under the mezzanine that protects the structure for a stated time, usually 30 or 60 minutes.
- Travel distance
- How far someone must walk to reach an escape route or exit, limited by fire safety guidance.
- Completion certificate
- The certificate issued by Building Control when work has been inspected and meets the Building Regulations.
- BS 5395
- The British Standard for the design of stairs, used alongside Approved Document K.
- Slab
- The concrete floor of the existing building that the mezzanine columns stand on.
- Plate load test
- A site test that measures how much load the ground or slab can take under a steel plate.
- Goods lift
- A lift for goods only, not passengers, used to move stock between mezzanine levels.