The Bi-Fold has two leaves that are hinged together at approximately mid opening height. When opening the leaves fold together coming to rest, horizontally, directly beneath the lintel. The folded/open door projects approximately one quarter of the door (height) externally and one quarter internally.

The Bi-Fold is most suited to large openings where tall vehicle access is required. Fire-stations and Ambulance-stations frequently have Bi-Fold installed.

Even with two leaves, the counterweight balanced Bi-Fold has few moving parts. Architectural aesthetics, reliability and long service life make this our most popular product for commercial vehicle access.

The ARCO Bi Fold is custom built for each specific application.The reliability and action of this door make it suited for large to extremely large openings;
-Emergency service applications
-Car park entries
-Show rooms

The door frame is typically constructed from hollow, rectangular, steel sections.
These provide high strength and rigidity with low weight.
Often, doors of this type (when used for wide openings) incorporate trussed frame members.
Other components, eg. tracks, brackets etc . are fabricated from steel sections.

The standard finish is a two pack paint system, powder coating may also be available depending on frame size and colour.
Hot dip galvanizing is often specified where corrosive environments or seaside locations necessitate.

The door can be designed to accept a wide variety of cladding and glazing materials.
-Toughened/laminated glass, including double glazed units.
-Composite paneling.
-Common sheet-metal roofing/wall cladding
-Rigid plastic sheeting
-Thermally insulated panel
Most Bi-Folds are glazed. Typically glazing beads are 50mm wide. Glass type and panel size is regulated by industry standards.

The Bi-Fold door requires operational clearances as well as permanent space for its accommodation. These dimensions vary depending on the application and the size and weight of the door.
The door moves on tracks, installed behind the opening nibs. It fits between the nibs, floor and lintel. As the door opens the leaves rotate from the vertical (closing the opening) to the horizontal (under the lintel at the top of the opening). When open, the door projects one quarter outside/one quarter inside.
Operational clearances must be carefully accounted for as they impinge on other design criteria, eg proximity of vehicles in front of and behind the door.
Please Refer to Technical sheet C5 for clarification and approximate clearance requirements.

The Bi-Fold is automated by the use of:
-A drive unit, which includes a torque limiter and independent limit switches with variable speed control.
-Motorisation tracks/guides
-An overhead drive shaft, between tracks
-A control system, which may include safety features such as photo beams, loop detectors etc.
When a power operated Bi-Fold door is ordered these items are included as integral components of the door. Motorisation may be fitted to an existing manual door, but this may require extensive modification.

Locking is normally provided on manual operated doors only.
Pad bolts are fitted internally/externally to allow the door to be latched in the closed position. These can be fitted with padlocks for additional security.
Motorised doors are usually locked via the drive unit, however additional security is available by incorporating powered mechanical or magnetic locks.