ASFP Clarifies The Question Of Overcladding Reactive Coatings
If, however, cladding or other protection systems are to be subsequently installed abutting the steel beams and columns and space is limited, the performance of an intumescent coating, in a fire situation, could be compromised.
To that end, the Association for Specialist Fire Protection (ASFP) Technical Committee has issued a guidance statement in order to avoid unintended limitations to fire exposure when cladding or other protection systems from part of the construction. The Association advises the following:
In general, a minimum gap of 50 times the dry film thickness of the reactive coating is recommended, to allow adequate expansion of the reactive coating in a fire. This guidance applies to the gap between the cladding and the flat surfaces of the protected steel section, as well as the flange tips, unless specific fire tests prove otherwise. Gap sizes, however, may be reduced where the manufacturer has specific fire test evidence. Continuous linear fixings or spacers for the cladding, in timber or metal, should be considered as part of the main steelwork and duly protected from fire, unless other supporting fire test evidence can be provided to justify alternative action. If any cladding/protection system totally encases the coated steel section and the cladding itself provides the required fire resistance, to a recognised fire testing protocol, then no spacing is required.
Whilst this stance on the part of the ASFP may not be welcome news to all, the Association believes that it has a legal duty of care to issue this guidance since it could affect the appropriate use of cladding products intended for decorative, or mechanical protection of the steelwork, in conjunction with steelwork protected from fire by reactive coatings.
The ASFP represents more than 70 manufactures and installers of passive fire protection boards, cementitious sprays and decorative intumescent reactive coatings for structural steelwork in buildings. These materials ensure resistance to fire attack, as required by the guidance in Approved Document B in support of the Building Regulations.
Anyone with further queries should contact the ASFP, Tournai Hall, Evelyn Woods Road, Aldershot GU11 2LL. Tel: 01252 357832. Fax: 01252 357831. Email: info@asfp.org.uk Alternatively, the BRE Fire division (Tel 01923 664000), or Bodycote Warringtonfire (Tel 01925 655116), can be consulted.
© Copyright 2011 Means Of Escape Terms & Conditions Privacy Policy
Copyright © 2011 Think Agency - Website Designers Kent