Image by Flickr.com, courtesy of Björn Láczay
Scaffolding is the term for a temporary frame structure built as a raised work site and capable of supporting materials and workers. Designed and built to stack to the required height, they are capable of becoming very elaborate depending on the need, height requirement and structure in need of access. Good sturdy foundations are important, and various ties and anchors are needed to stabilise the modular structure and assure the safety of both workers and the public.
Birdcage scaffolds consist of regularly spaced poles arranged in parallel lines and resemble large birdcages. Wood planks are placed over the line of poles, while diagonal brace bars offer both lift and stability. Individual lift heights are designed to be stacked and are typically no higher than 3 feet high each. Birdcages should be braced or tied to guarantee stability and resist wind force.
Single Pole Scaffolds
Single pole scaffolds have a platform resting on simple crossbeams, with the outside ends supported by ledges or holes in the building wall. Because this scaffold type is entirely dependent on the structure it is placed on for support, it is not ideal for applications in which the actual external structure is to be removed or heavily altered. Easy to raise and stabilise, these are common light duty frameworks.
A suspended scaffold is a balanced platform and is raised or lowered as needed. This type is usually used by window washers and is suspended from a structure positioned overhead. Weight of this type varies by use and load required and lift is ensured by the use of heavy suspension ropes, pulleys and weights. Tiebacks are utilised for connection to predetermined structural members of the building.
Cantilever scaffolding is a standalone scaffold constructed to angle out from a structure when it is impossible to base the scaffolding on the ground due to an obstacle. It is generally supported on only one end. Although application is sometimes limited, cantilever scaffolds are generally easy to erect and have the ability to hold an average workman and supplies. Cantilever styles eliminate the need for full poles and frame in front of a structure. They are usually positioned near balconies or ledges for access.
Scaffolding consists of poles made from either aluminium or steel and come in a variety of lengths. The working surface is made up of treated wood of thickness suitable to hold workmen and supplies. Couplers are used to hold the tubing in place, and wood sole boards are placed under bases if the ground is soft. Various other add-on items are available including ladders, anchors ties and lifting baskets.
- "Elevated Work Platforms and Scaffolding: Job Site Safety Manual"; Matthew Burkart, Michael McCann, and Daniel Paine; 2004
- "Handbook of Rigging: For Construction and Industrial Operations"; Joseph MacDonald, William Rossnagel, and Lindley Higgins; 2009
- Image by Flickr.com, courtesy of Björn Láczay