3. PLANNING THE DEMOLITION WORK
The principal contractor( or the demolition contractor if there is no principal contractor) should take all reasonable steps to obtain the designer’ s safety report.
For demolition work, there may be a number of designer safety reports available, including:
• the report prepared for the original construction of the structure( if available)
• any reports prepared for subsequent additions or alterations to the structure( if available), and
• where a designer is engaged for the demolition work, the report provided to the person commissioning the design of the demolition work.
Designers who develop demolition specifications or procedures for the demolition of a structure should consider the possible work methods available and associated health and safety risks. Designers should then take into account the proposed demolition method and control measures available when producing any final design documents for the demolition of a structure.
If as-built design documentation is not available, or there is a concern that the structure has been damaged or weakened( e. g. by fire or deterioration), or plant is to be used on suspended floors, then a competent person( e. g. a qualified structural engineer) should conduct an engineering investigation and deliver an‘ engineering investigation report’. Some issues that may be considered when undertaking an engineering investigation are listed in Appendix C.
The following design matters should be taken into account when considering demolition risks:
• the stability and structural integrity of the structure at all stages of demolition, including assembled portions, single components and completed sequentially erected braced bays
• the maximum permissible wind speed for partially demolished structures
• the effect of the proposed demolition sequence on stability
• the stability requirements for all components of the structure as it is sequentially demolished according to the structural engineer’ s requirements
• the proximity of adjacent or adjoining buildings
• the competent persons assessment of loadings at all stages of demolition
• the provision of clear instructions for temporary bracing
• the plant to be used for the work, including the size, type, position and coverage of proposed demolition crane( s) should be indicated on a site plan, locations such as unloading points and storage areas( if any) should be shown
• the need to ensure that the ground is compacted to any design specifications to enable plant to be moved and used safely at the workplace
• the proposed methods for handling heavy, bulky or awkward components
• the need for specific lifting arrangements to be detailed on structural member drawings to facilitate safe lifting
• the handling, lifting, storing, stacking and transportation of components, depending on their size, shape and weight
• the provision of safe access and safe working areas.
Further guidance on the safe design of structures can be found in the Code of Practice: Safe Design of Structures.
CODE OF PRACTICE | DEMOLITION WORK 11