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