No-one who was at Warwick in the early 70s will forget the problem of the White Tiles. The early buildings on Main Site are moderately flexible steel-frame structures which move and distort as the clay beneath expands and contracts with the seasons. It requires care or ingenuity to clad such a building with a rigid layer so that the layer stays on. The attraction of the white tiles with which these buildings were clad it that they are weatherproof and require little maintenance. Not many years after the completion of some of these buildings it became evident that there was a problem. Where the flexing was greatest the tiles pinged off to the danger of passing pedestrians, leaving unsightly gaps. The architects blamed the consultants who blamed the contractors who blamed the consultants who blamed… and in the end the University sued all three jointly.
The remedial action depended on the stage at which the building was built. The Rootes residences and the Chemistry building, for example, were given an additional cladding of white-coated metal strips behind which, unseen, the tiles could fall off without endangering pedestrians or letting the rain in. The Humanities building had its tiles stuck on in small areas with flexible mastic between one area and the next instead of mortar, so as to reduce the overall rigidity of the layer of tiles. I worked in the Physics building, where it was decided that the treatment would be to improve the adhesion of the tiles by filling with epoxy resin any gaps that had been left or had opened up between the tiles and the concrete behind. I daresay these days such voids would be detected using ultrasonic methods, but the technique used was to tap each tile a number of times with what looked like a xylophone hammer to see if it sounded hollow or not.
There are a lot of tiles on the Physics building, and for months it seemed that it was being attacked by a rather stupid woodpecker. All the hollow-sounding tiles were marked in blue crayon with a cross, then holes drilled at either side of each marked tile or group of tiles, and finally the epoxy forced into the hole at one side until it squirted out at the other. It was many years before the crayon marks and runs of epoxy were finally cleaned off.
In the end the University won its court case and was compensated for the cost of the white tile problem. Those of us working in the Physics got no compensation for the months of tapping and drilling. Thirty years on, the tiles do seem to have stayed on, though.