Ceiling collapse can be avoided with the correct specification

  • 1 May 2014

Critical to the safety and security of a suspended ceiling and its associated equipment are the top fixings. BS EN 13964:2004 Suspended ceilings – Requirements and Test Methods states that “the type and number of top fixings shall be specified,” and “the selection of top fixing method shall be detailed on the relevant drawings”. However, it is very rare that the top fixings are specified.

When an insufficient number of fixings are used, a ceiling is prone to failure

Without this specification as is so often the case, the installer or specialist contractor is left to select the fixings they feel are most appropriate for the application, without fully understanding the parameters of the project or installation requirements. The architect or designer is best placed to advise and specify the fixings, based on their knowledge of the applied load, the base material into which the top fixing is to be installed and any other environmental factors that might impact on the ceiling or fixing after its installation.

The Best Practice Guide to the Installation of Top Fixings for Suspended Ceilings from AIS, in conjunction with the Construction Fixings Association provides recommendations on the selection process. These include the importance of identifying the applied load – both the current loading and any future changes. What material the ceiling is being hung from is also a crucial piece of information. Finally, any environmental factors – moisture from a corrosive atmosphere such as a swimming pool for example, or buildings subject to particular structural vibration – must be considered in order to specify the optimum fixings, according to the application.

Next, the structural integrity of the proposed specification needs to be checked; will it take the load of the ceiling and anything else to be suspended from it, now and in the future? Will the fixing carry the load? Finally, a preliminary test is needed where there is no European Technical Assessment in place to provide data on the recommended load in the substrate to rule out any doubt. It is important for the specifier to remember that, even where correct fixings are used, there may still be instances where a ceiling fails and the fixings are found to be the cause of the problem, due to incorrect installation, or incorrect size. Issues can be avoided by following the manufacturer’s instructions for both the ceiling system and the fixings themselves.

The structural integrity of the proposed specification needs to be checked and a preliminary test should be carried out

Equally, following trades may implement modifications that, in time, could compromise the specification and safety of the ceiling. For example, suspension wires or hangers might be cut or removed to make space for new services. In the worst examples, these services are suspended from an existing fixing that already has to support the ceiling. In other instances, hangers are replaced with inappropriate substitutes, such as cable ties, that just don’t stand up to the job.

Access to the ceiling void should be carried out with the help of a ceiling installer because tiles need to be removed correctly from the exposed and concealed grids

The weight applied to a ceiling is an important factor. Access to the ceiling void should ideally be carried out with the help of a competent ceiling installer because tiles need to be removed correctly from the exposed and concealed grids. Some systems call for specialist tools to remove the tiles – not screwdrivers and an element of brute force, which can damage the pips holding the tiles in place, ultimately leading to possible partial ceiling collapse.

Equally, excess loading can be applied as a result of wires laying on the tiles, cable trays, ductwork, lighting, air handling units, signage and other accessories. Such components must be supported independently of the ceiling system itself. Ceiling failure and top fixing failure can be the result
of structural vibration. Structural vibration can cause the anchors holding the ceiling to weaken, eventually leading to collapse. The education environment is one in which structural vibration can occur. One case where heavy carts were regularly pushed over an uneven exposed floor caused enough vibration to result in ceiling fixing failure.

The substitution of a ceiling component that has been specified by the architect or designer for another component can have disastrous consequences. Its compliance with the required standards – and any manufacturer’s warranty –
is drastically compromised and even voided.

Knowledge and training are the keys to the accurate specification and safe installation of a suspended ceiling. Not only should these components be selected by a competent person, they should also be installed by a competent person who understands the requirements. A specialist contractor who is a member of a specialist trade association will have access to the right knowledge and training.

Leave a Reply

Latest news

Abloy
Renderplas

Renderplas shadow gap beads throw shade

For architects and designers looking to avoid traditional skirting boards, architraves and cornices, Renderplas offers its range of PVC plasterboard shadow gap beads for dry lining systems.

Posted in Articles, Building Industry News, Building Products & Structures, Floors, Interior Design & Construction, Interiors, Posts, Render, Restoration & Refurbishment, Retrofit & Renovation, Walls

MCRMA

First MCRMA members’ roadshow takes place at Siderise

Members of the MCRMA, the trade association for the metal cladding and roofing industry, had an exclusive opportunity to explore and discuss the changes affecting the construction sector at the first of the association’s roadshow events hosted by Siderise at its HQ and manufacturing facility in South Wales.

Posted in Articles, Building Associations & Institutes, Building Industry Events, Building Industry News, Building Products & Structures, Building Regulations & Accreditations, Building Services, Cladding, Exhibitions and Conferences, Health & Safety, Restoration & Refurbishment, Retrofit & Renovation, Seminars, Walls

BMBI