Base collar (starter)
A short tube with one disc that sits on the base jack of a modular scaffold and gives the first ledger connection just above the ground.
Scaffolding glossary
From base jack to end guard rail: 50 parts explained, with their variants and what to check on used material.
StructureDecksGuard rails and toe boardsBracketsTies and anchorsCouplers and connectionsBase and supportsAccessProtectionSmall parts
Structure: frames, standards, ledgers
Buttress and outrigger
Inclined props from scaffold to ground that take over the job of ties where the wall may not be drilled, or steady the scaffold during erection.
Compensation frame and short frame
Low frames set beneath the standard frames to take up slopes and steps in the ground, or to bring a working level to an exact height.
Double ledger and lattice ledger
A ledger with top and bottom chord, braced by posts or a truss, used where a single ledger would bend too much under wide bays or heavy loads.
Horizontal diagonal brace
A brace laid diagonally in the horizontal plane of a lift, keeping the scaffold from twisting or shifting in plan.
Lattice girder (bridging beam)
A steel or aluminium truss that spans a gap where no uprights may reach the ground, carrying the scaffold built above it.
Passage frame
A wide frame used in the bottom lift so that a pavement or entrance stays open under the scaffold while the lifts above continue as normal.
Rosette (node disc)
The steel disc welded to a modular standard every 0.50 m; ledgers, diagonals and brackets wedge into it, up to eight parts at one node.
Scaffold tube
The 48.3 mm steel or aluminium tube that fills every gap a system part cannot – as brace, rail, tie member or complete tube-and-fitting scaffold.
Standard (modular upright)
The vertical tube of a modular scaffold with a connection disc every 0.50 m; it carries all vertical loads and takes every ledger, brace and bracket.
Tubular ledger
A round steel tube with a wedge head at each end that links two standards; it serves as guard rail, bracing and deck support in one.
U-ledger and deck transom
A transverse ledger with an upward-facing U-profile into which deck claws hook; it carries the working platform of a modular scaffold.
Vertical diagonal brace
The inclined brace that turns a rectangular bay into two triangles and stops the scaffold from racking along the facade.
Vertical frame
The welded frame of two uprights and a top transom that carries every lift of a frame scaffold and sets platform width and lift height.
Decks
Access deck with ladder (hatch deck)
A platform unit with a hinged hatch and a ladder underneath that lets workers climb inside the scaffold from one lift to the next.
Aluminium deck and combi deck
A lightweight platform unit made of an aluminium profile, or an aluminium frame with plywood infill, for scaffolds that are built up by hand.
Steel deck
A galvanised steel platform unit that hooks onto ledgers or frame heads and forms the hard-wearing working surface of a system scaffold.
Timber scaffold board
A timber platform unit, either a system deck with steel end fittings or a loose board laid across ledgers or tubes.
Guard rails and toe boards
Advance guard rail system
Posts and telescopic rails that let scaffolders install the guard rail for the next lift from below, so the edge is protected before anyone steps up.
Double guard rail
A welded component that combines the top guard rail and the intermediate rail in one part, saving handling time on every bay.
End guard rail
The guard rail fitted across the open end of each scaffold lift, sized to the scaffold width, to close the fall edge at the stop end.
Guard rail
The top member of the side protection on a working lift, fitted at least 1 m above the deck to stop people falling from the platform edge.
Guard rail post
A short tube pushed onto the legs of the top frames that carries guard rails and toe boards on the last working lift of a frame scaffold.
Toe board
An upright board at the edge of the deck, at least 150 mm high, that completes the side protection and stops feet, tools and materials going over the edge.
Brackets
Bracket brace
A diagonal tube that supports an outside bracket from its outer end down to the standard of the lift below, forming a load-bearing triangle.
Inside bracket
A short cantilever fixed to the inner standards that carries one extra deck towards the wall and closes the gap between scaffold and facade.
Outside bracket (cantilever)
A bracket that projects outwards from the outer standards, usually by 0.73 m for two decks, to create catch platforms, fans or extra storage space.
Ties and anchors
Eye bolt and plug
The 12 mm eye bolt screwed into a wall plug that gives the scaffold tie its fixed point on the building and carries the full anchor force.
Scaffold tie (wall tie tube)
Hook-ended 48.3 mm tube linking the scaffold to an eye bolt in the wall, so wind and overturning forces pass into the building.
V-tie (triangulated tie)
A pair of tie tubes set in a V to two eye bolts, so that forces both across and along the facade are taken into the wall.
Couplers and connections
Half coupler
A coupler with only one jaw for a 48.3 mm tube; the other side is welded to a component or ends in a threaded bolt for fixing to steel or timber.
Right-angle coupler
The coupler that clamps two 48.3 mm tubes rigidly at 90 degrees so the joint neither rotates nor slips; tested and classified under EN 74-1.
Sleeve coupler and spigot
Parts that extend tubes and standards in a straight line: the spigot or joint pin centres from inside, the sleeve coupler clamps from outside.
Swivel coupler
A coupler whose two jaws rotate on a rivet, joining two 48.3 mm tubes at any angle – the standard fitting for tube diagonals and raking braces.
Wedge head and wedge
The slotted head on ledgers, braces and brackets that slides over the rosette and is locked by a driven wedge – a rigid node with no bolts.
Base and supports
Base jack (adjustable base)
A threaded, height-adjustable foot at the bottom of each scaffold leg that levels the first lift and carries the leg load into the ground.
Base plate, fixed and swivel
A steel plate with spigot that spreads the load of a scaffold leg; the swivel type tilts to sit flat on sloping ground while the leg stays vertical.
Scaffold castor
A braked swivel wheel that replaces the base jack and turns a scaffold tower or small birdcage into a mobile unit on firm, level floors.
Sole board (base support)
A timber board or pad laid under base jacks to spread the leg load over soft or uncertain ground so the scaffold cannot settle.
Access: ladders and stairs
Scaffold ladder
The short ladder that links the lifts through hatch decks inside the scaffold, so people climb within the side protection instead of outside it.
Scaffold stairway and stair tower
Stair flights with handrails built into their own tower in front of the scaffold, giving upright, hands-free access to every lift.
Stair guard rail
The inclined rail frame that follows a scaffold stair flight on its open side, with handrail and knee rail, and joins the landings above and below.
Protection: nets, fans, roofs
Protective fan (canopy)
An outward-sloping, close-boarded platform on the scaffold that catches falling debris above pavements, entrances and parking spaces.
Roof edge protection screen
A screen about 2 m high on the top lift that catches people and material sliding off a pitched roof before they fall over the eaves.
Scaffold net and sheeting
Nets and sheets fixed to the outer face of a scaffold to hold back dust, spray and debris; sheeting also keeps out rain but greatly increases wind load.
Temporary roof (weather protection roof)
A temporary roof of aluminium trusses and keder sheets carried by the scaffold, keeping rain off open roof structures and work areas.
Small parts
Deck lock (anti-lift device)
A bar, clip or hinged latch that holds scaffold decks down so wind, knocks or a step on the far end cannot lever them out of place.
Drop-lock pin and spring clip
Small locking pins that make stacked scaffold joints resist tension and stop push-on parts such as guard rail posts from being lifted out.
Pins, bolts and clips
Loose bolts, pins and clips that join lattice girders, standard joints and telescopic parts and keep those connections from working loose.
Transport stillage and mesh box
Steel racks, pallets and mesh boxes that keep scaffold parts sorted, stackable and liftable by forklift or crane in the yard, on the truck and on site.