During their lifetimes, buildings are refurbished or renovated many times, often in order to provide functions not envisaged when they were designed. As a result, the structure may no longer be capable of achieving the required fire resistance and the presence of defects or material degradation may mean that it can no longer achieve the performance assumed when it was built. Many large residential and commercial buildings built in the post-war period of reconstruction incorporate reinforced concrete flooring systems.

This Information Paper provides information on assessing the fire performance of existing reinforced concrete flooring systems using tabulated values from national standards and the Eurocode for the design of concrete structures, as well as experience from assessment of existing buildings and research by the Fire Research Station (now part of BRE Group). It will help clients, contractors and building control authorities to estimate levels of performance provided by specific forms of construction, many of which are incorporated within existing buildings but are no longer in widespread use as current construction systems.

Contents

Introduction

Concrete in fire

Tabulated data for reinforced concrete floors

Alternative forms of construction

- Hollow pot floors

- Wood wool slabs

- Other proprietary systems

Methods to enhance the fire resistance of existing floor systems

Conclusions

 

A4 12pp

Available on or after 29/3/2012.

References