Cement – British Standard & Types

Cement – British Standard & Types

The British Standard for ordinary Portland cement is BS EN 187-1. Known as Ordinary Portland, there are two basic colours – one sold as ‘Rugby’ cement, the remainder as OP cements. Some have additives included to aid workability. Sold in paper sacks or long-life sealed plastic, they are available in 25kg packs from all Builder’s merchants.

Rugby cement is dark grey in colour, whilst most OP cements tend to be light grey. White cement is available for lighter coloured mortar requirements, and is also useful when working with light coloured paving, where a grey mortar may leach through porous materials and show on the surface. (See White Cement.)

When working on some clay grounds, where sulphates (sulfates) may cause problems with cement degradation, a Sulphate Resistant Portland cement type V in accordance with ASTM C150 or sulfate-resisting Portland cement in accordance with BS 4027 quality assured cement should also be available from most Builder’s merchants. (See Sulfates and Their Effects on Concrete.)

It is important that, whatever type of cement you decide to use, you need to continue using the same product, manufactured by the same company to avoid any colour variations in face work or pointing. Careful batching when mixing with sand and water is crucial to maintain strengths and mortar colours and workability.