PSD Residential Flooring

a solid base for the future

Sulfate Attack........................... page 1 | 2 | 3

Who is affected by Sulfate Attack ?

Whilst scattered cases of sulfate attack to floor slabs have been reported to the Building Research Establishment (BRE) from across the UK, the large majority have been located in and adjacent to the coal fields and related industrial Map of coal mining areascentres that ultilised the coal for iron and steel production. Prominent amongst the affected areas are the Midlands from Coventry and Birmingham northwards to Stoke-on-Trent and east Cheshire, the North-east of England from Doncaster northwards to Newcastle upon Tyne, and the Midland Valley of Scotland between Glasgow and Edinburgh. In these areas the sulfate-bearing material typically comprises burnt colliery spoil (called locally red shale or red ash) taken from coal mine tips, coal combustion ashes from furnaces (often called black ash) and blastfurnace slags from the smelting of iron. Elsewhere, clusters of sulfate attack have been associated with the use of certain geological strata as fill material, for example the use in the Whitby - Middlesbrough region of sulfide and sulfate-bearing shaley mudstones of the Whitby Mudstone Formation and Cleveland Ironstone Formation (known locally as Cleveland shale), though with this material internal expansion is often the key problem. The individually scattered cases of sulfate attack known to BRE have generally been associated with the local use of coal combustion ashes or of brick rubble that has been contaminated with gypsum (calcium sulfate) plaster. Hull is one area reported as formerly having many properties with such plaster- contaminated rubble, the source of which were buildings destroyed by World War 2 bombing.