Summary of the new European Standard BS EN 771-1 for clay bricks
Key points about BS EN 771-1: 2003
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BS 3921 has been superseded by BS EN 771-1.
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Classifications for durability designation and active soluble salts content will now be separately classified but most products will remain the same e.g. a brick currently described as "FL" will now become "F2 S2" meaning suitable for severe exposure (F2).
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New test methods have been developed for compressive strength and water absorption dimensions - most brick types will show apparent changes.
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Dimensions - all bricks will be sold with to two categories known as Dimensional Tolerance Range which is defined as T for tolerance and R for Range classification, there are a number of classifications, in most cases T2 R1 would be the most common classification. In order to determine compliance the use of specially calibrated instruments to accurately measure the length, width and height of a brick must be used.
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Visual acceptability - P.A.S 70 provides guidance on how to assess visual acceptability. This document emphasizes it is the overall brickwork and not individual units that should be assessed, in essence, if a chip or blemish is not visible from 3 metres it should be deemed acceptable.
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CE marking will ultimately denote conformity to BS EN 771-1 - currently CE marking is not a legal requirement of product sales/use within the UK. This means that some clay brick products may exhibit the mark while others will not immediately do so. All clay brick products are, for the foreseeable future, able to conform to BSEN771-1 with or without CE marking being used. However, Hanson will be CE marking products from April 2006.