Whether or not the claim of sustainability is made, the issue prevails. Keith Bothwell's useful injection (Letters, aj 18.11.99) was with reference to a building that claimed to be 'sustainable' but was not. Your description of Bristol's Severnshed Restaurant (aj 25.11.99) does not make that claim (though being re-use of a building might have), but does audaciously draw attention to the use of 'specially chosen' Chesil beach aggregate for polished concrete floors.
The 18km of Chesil beach protect the Lyme Peninsula coast from Atlantic storms and surges. The village of Chesil itself nestles below the shingle crest, which is itself frequently damaged by eroding storms, requiring at times the importation of shingle for topping up. Commercial erosion by extraction or purchase is neither ecological, sustainable nor commercial sense, whether or not it is done under local-authority licence. In any case, and as I understand it, removal of beach material anywhere is now illegal.
Before the use of beach aggregates catches on, the point may need to be made that building sustainability has to take account of materials selection and source, and the impact upon environments other than only those of the building and its site.
James Lewis, Datum International, Marshfield near Chippenham, Wiltshire