HC Deb 18 March 1985 vol 75 cc340-1W
Mr. Rooker

asked the Secretary of State for the Environment to what he attributes the process of carbonation in his Department's main office building and the spalling of concrete with rust staining; whether calcium chloride was used as an additive to the concrete and if tests have been carried out on the level of chlorides in the concrete; and if he will make a statement.

Sir George Young

I will answer this question shortly.

Mr. Rooker

asked the Secretary of State for the Environment when his Department's main office building in Marsham street, London, was designed; over what period it was constructed; when it was completed; what was the cost of the construction; who were the architects; and who were the builders.

Sir George Young

No. 2 Marsham street was designed by the Ministry of Public Building and Works in conjunction with the architects, Robert Atkinson and Partners. Design work commenced in 1959. A contract for foundation and basement work was undertaken between July 1963 and November 1964. The main contract, undertaken by Bernard Sunley and Sons Limited, started in November 1964 and was completed in March 1971. Final fitting out was handled as a separate contract and occupation of the building was phased throughout the summer of 1971. The total cost of construction, excluding professional fees, site purchase and clearance was £7.975 million.

Mr. Rooker

asked the Secretary of State for the Environment what is the estimate of the future life of his Department's headquarters building; and what remedial works are planned, or are necessary to the main structural elements.

Sir George Young

Campbell Reith Hill, the PSA consultant investigating the concrete defects in the superstructure of 2 Marsham street indicate that, provided the sample cover readings are representative of the whole building, then the sixty year design life should be achieved.

First-aid remedial action to spalled areas has been undertaken.

When repairs start, access to the end walls of the buildings will be provided so that a corrosion survey, a full cover depth check and carbonation survey can be completed. Areas where these tests show that spalling of the concrete is likely will have the concrete removed, the reinforcement cleaned and the concrete repaired. Consideration will be given to applying a membrane to the entire surface of these walls to prevent further carbonation, ingress of moisture and air, so as to prevent corrosion of the reinforcement.

Cracks to the precast concrete mullions are being monitored for movement.