Fire safety in high rise residential buildings was put under the spotlight in the wake of the 2017 Grenfell Tower tragedy, leading to the introduction of the Building Safety Act 2022. The legislation is intended to improve the design, construction and management of higher-risk buildings. Building regulations require new buildings to be designed and built to limit the spread of fire and to help residents escape in the event of a fire. Here, Jake Green, Head of Technical Engagement with Scolmore Group looks at the regulations covering the selection and erection of wiring systems to minimise the spread of fire.
BS 7671
Section 527 details the requirements of BS 7671 for the selection and erection of wiring systems to minimise the spread of fire.
The general requirements are:
- That a wiring system is installed so that the general building structural performance and fire safety are not reduced (527.1.2)
- Wiring systems passing through building elements openings shall be sealed to the degree of fire resistance prescribed for the particular element (527.2.1)
- 527.2.4 details the necessary sealing arrangements.
There is no requirement within BS 7671 for installers to be registered with a specific registration body to carry out such work.
Firestopping of service penetrations
The guide, ‘Firestopping of service penetrations Best practice in design and installation’ published by the Finishes and Interiors Sector Ltd is supported by ASFP, BESA, BSRIA and GPDA and has a foreword by Dame Judith Hackitt. This guide was issued post the Grenfell Tower tragedy.
The guide (page 45) highlights third party product certification schemes for passive fire protection products. The guide states, ‘Using correctly installed certificated products provides a powerful demonstration that due diligences have been served.’
There are third party certification schemes for penetration seal installers. These include, WarringtonFire, IFC, BRE and BM Trada. Furthermore, the IFE have a Level 2 Certificate in Passive Fire Protection. This qualification has been developed with the Association for Specialist Fire Protection (ASFP).
However, the competence of the installer sits differently to that required of the product. As long as the product meets the requirements of the specifier and with the requirements of BS 7671, the installer is responsible for its correct installation.
BEAMA Technical Bulletin
BEAMA have recently (2023) published a technical bulletin covering Intumescent and acoustic pads and covers.
This brief guide does highlight a concern regarding the use of such materials. Wiring accessories are tested when mounted on a standard wall box (plastic or metallic) having no added firestopping material. BEAMA have undertaken tests and found that overheating may occur leading to products exceeding their design temperature, with accessories containing electronic equipment being particularly prone to such risks.
BEAMA states the following:
‘Intumescent and acoustic pads and covers shall not be used unless approved by the manufacturer of the wiring accessory. Approval shall take into account the influences of the pad(s) and cover(s) upon the relevant requirements of the accessory product standards e.g., temperature rise and internal clearances.’
Conclusion
It is clear that the question raised is not one that simply covers the seals themselves and the regulatory requirements and other guidance, but one that addresses manufacturer concerns about the reliability of the accessory once intumescent pads are installed.
However, as stated earlier in this article, the competence of the installer sits differently to that required of the product. As long as the product is third party certificated and meets the requirements of the specifier along with the requirements of BS 7671, the installer is responsible for its correct installation.