With so much else to compete with in London, the three-day Building Limes Forum (BLF) conference and limes fair at the Old Royal Naval College in Greenwich in September did not achieve quite the publicity that had been hoped for during London\'s \'Open House\' week.

The BLF did not manage to get a separate mention on the Open House website or in its literature and both the specialist and general press had a lot else to report.

Nevertheless, with 64 people at the conference and 120 members attending the three-day event the BLF do not consider it in any way a failure.

Being in London, they took the opportunity to discuss the chalk limes that were used in London and the South of England before the advent of Ordinary Portland cement in the 1860. The chalk lime came in two forms, one sold as chalk lime and one as stone lime. Stone lime was still made from chalk, but chalk from lower beds that naturally contained clay and produced a stronger mortar.

Changes to the European standards on lime mortars, which are expected to take effect in 2009 and to which the BLF have had a significant input, should make it possible to use these mortars again, which will be important for conservation work in London and the South.

The lime industry has often complained that the standards for lime mortars encompassed in EN459 have been based on the standards used for hard cement. However, changes now proposed deal much more specifically with lime.

Ian Brocklebank, the BLF chairman who organised the Greenwich event with, in particular, treasurer Michael Beare and Between Time conservation builders, says the BLF are particularly pleased with the proposal to introduce a new category of hydraulic lime to be known as NHL1 with a strength below 2N/m2. This is the category that will encompass these chalk limes.

There will also be changes to standards governing hydraulic limes that contain pozzolans and other additives.

These have sometimes had poor reputations because users are not always sure what they contain and there has been no requirement for the contents to be listed. Under the new proposals for EN459 they will be renamed \'preformulated limes\' and their contents will have to be identified.

Next year the BLF\'s conference is on the Isle of Man.