Structural stability during alteration, demolition and dismantling
What you need to do
The law says that all alteration, demolition and dismantling work should be carefully planned and carried out by competent people to avoid unplanned structural collapse.
The law requires commercial clients to provide contractors with relevant information about a building’s structure, including stability and structural form and any significant design assumptions, suggested work methods and sequences. The contractor must then use that information to plan and carry out the work safely.
Key requirements are:
- Survey and assessment
- Preventing structural collapse
- Arrangements for demolition
- Consulting building control departments
What you need to know
Workers and passers-by can be injured by premature and uncontrolled collapse of structures, and by flying debris.
Survey and assessment
A competent person should do a thorough structural survey and assessment before any potentially load- bearing parts of a structure are altered.
The structural survey should consider:
- The age of the structure;
- previous use;
- type of construction; and
- any nearby buildings or structures.
This information should be used to determine the steps required to prevent any collapse.
Preventing structural collapse
A competent person should decide the method and design of temporary supports. Temporary support provided must be designed, installed and maintained to withstand foreseeable loads and structures should never be overloaded.
Arrangements for demolition
Demolition or dismantling arrangements should be written down before the work begins. This safe system of work may be in the form of a safety method statement identifying the sequence required to prevent accidental collapse of the structure.
In addition to the design and method of temporary supports a safe system of work may include:
- Establishing exclusion zones and hard-hat areas, clearly marked and with barriers or hoardings;
- covered walkways;
- using high-reach machines;
- reinforcing machine cabs so that drivers are not injured; and
- training and supervising site workers.
Consulting building control departments
You should consult the building control department of the local authority in the area where a building is located before any structural alterations are made to a building.
The local authority is the enforcing body for building regulations.
- Establishing exclusion zones when using explosives in demolition CIS 45
- Health and safety in construction HSG 150
- Avoiding danger from underground services HSG47
- Safe use of lifting equipment L20
- Excavation: What you need to know as a busy builder CIS64
- Basement construction: What you need to know as a busy builder CIS66