I'm wondering what the law states regarding having a structural survey completed for farm yard barns being demolished. Some of the buildings have ACMs and as such a Asbestos survey was under taken and an Asbestos removal company appointed to remove ACMs prior to the demolition. Whilst they were removing a sheet from an internal ceiling, the rafter came away, I have been told that a structural survey should have been completed prior to the Asbestos survey. Surely the structural survey wouldn't have picked the loose rafter as it was being held in place by the Asbestos sheet.

CDM says some specific stuff about both structural stability and demolition in regulations 28 and 29, including

Reg 28: "All practicable steps shall be taken, where necessary to prevent danger to any person, to ensure that any new or existing structure or any part of such structure which may become unstable or in a temporary state of weakness or instability due to the carrying out of construction work does not collapse."

Reg 29: "The demolition or dismantling of a structure, or part of a structure, shall be planned and carried out in such a manner as to prevent danger or, where it is not practicable to prevent it, to reduce danger to as low a level as is reasonably practicable."

Note 28 says practicable, not reasonably practicable, which is an interesting debate all on its own.

BS 6187 is 'Code of practice for full and partial demolition'. While obviously not law, you'd want to complyu unless you had a very good reason not to. It has quite a lot of references to input from a structural engineer, and different degrees of inspection / survey / assessment, which can't really be condensed into much less space than the BS. However:

Section 5 is 'Planning and managing projects' which has a list of 'Key planning considerations', the first of which is 'Effective site knowledge' : "An assessment and survey of the site should be planned to identify the following, as far as possible. ... c) Knowledge and history of the structure, including form, materials of construction, structural interactions and location." [again, I note 'possible' not 'reasonably practicable'].

There's a whole section (9 pages) on 'Knowledge of the site'. It has all sorts of stuff in there about surveys. Interestingly, structural and stability generally appears in the lists higher up than hazardous materials (including asbestos), though the lists are not described as being in order of priority. Personally, however, I'd regard the risk of being buried under tons of rubble as a more immediate concern than that of whether the rubble had asbestos fibres in it.

Picking out some isolated clauses:

7.2.2 "On projects notifiable under the CDM Regulations 2007, the CDM coordinator should ensure that:

"a) the required information about the site and proposed work is collected in the principal contractor’s construction phase plan, which should incorporate the demolition plan (see 5.2.2.4);"

"5.2.2.4 Demolition plan

"All demolition, and partial demolition, activities should be planned and carried out such as to remove or reduce the risks to people to as low as reasonably practicable. The arrangements for carrying out such demolition, or partial demolition, should be recorded in writing before the demolition work begins, with a level of detail proportionate to the risks involved. For projects notifiable under the CDM Regulations 2007, the demolition plan should form part of the CCP prepared by the principal contractor."

"Avoidance of unplanned collapse: surveys

"Inspection surveys and assessments should be undertaken before work is carried out. The chosen methods of work should be such that demolition activities can be carried out in such a way that the unplanned collapse of any part is avoided by maintaining the structural stability of the remaining parts at all times. The
methods of work should therefore emphasise the importance of planning surveys, including those of the structure, being undertaken before any work is carried out. The types of surveys required should be explicit and the reasons given if they relate, for example, to features which might not be immediately apparent. Such surveys may be intrusive to ensure an adequate survey of the structure is undertaken. The surveys should permit structural assessments to form a fundamental basis for maintaining adequate structural stability at all times, so the terminology and requirements should be clear to avoid any misunderstandings."

I think it would be quite difficult to claim a demolition was proceeding in accordance with CDM without complying with the BS, and it would be almost impossible to comply with the BS without having a structural engineer of some sort having looked at the structure. Note, however, that the BS doesn't like the term 'structural survey', because of how it has been hijacked by estate agents: "CAUTION: The term 'structural survey' can cause confusion as its meaning can differ, for example, when the term is used by estate agents where the survey is for different purposes, such as valuation.")

Regarding:



I don't think that's true - cladding and sheeting stabilising structural members is not a particularly unusual phenomenon, especially in lightweight structures, and especially in older / poorly maintained structures. It would be reasonably foreseeable, in my view.

Somewhat chicken and egg surely? A structural inspection of the roof would (from limited information provided) have required a number of ACM panels to be removed. Sods law says it would involve the one that was going to fail.
'Foreseeability' depends on what could be seen or surmised about the structure in general - and who is doing the looking.
You now have a situation where you have knowledge of potential structural weakness so you now need some opinion as to whether temporary bracing etc. might be required to allow safe removal of the remaining asbestos.