The Design and Construction of Extension to British European Airways Engineering Base at London Airp

Aerated concrete is one of a group of materials described collectively as 'lightweight concrete.' The term 'lightweight concrete' is somewhat arbitrary; in the past it has been customary to consider as 'lightweight, any concrete of dry density not exceeding 100 Ib/cu. ft., but the use of reinforced units has led to concretes with a density of 110-115 or even to 120 Ib/cu. ft. A. Short and W. Kinniburgh

Mr. A. W. HILL (Member) said that he had read the paper with considerable interest, but felt that Mr. Mackay had overstated his case.