§ Mr. Lathamasked the Secretary of State for the Environment what action has been taken since 17 July 1979 in the light of the report of the Building Research Establishment entitled " The Integrity of Trussed Rafter Roofs"; and whether he will make a statement.
§ Mr. Geoffrey FinsbergThe main survey referred to in my answer of 17 July 1979 has now been completed and the results are being analysed. The survey covered site handling of trussed rafters, accuracy of erection and physical condition in service. Work at BRE on the corrosion of metal plate fasteners and the effect on the strength of the joint is continuing, together with longer-term studies of environmental conditions in roof spaces, including those with trussed rafters. A survey of the quality control exercised in the manufacture of finger joints has been completed and the results will be discussed with the British Woodworking Federation shortly. I understand that the Timber Research and Development Association is examining the effect on the strength of metal plate fasteners of embedding them in finger joints. The symposium which the Institution of Structural Engineers held in February this year on the design aspects provided a valuable exchange of views.