In article ,
Antony Gelberg wrote:
Here are some "clues": the block was purpose-built in 1986.

The regs requirement for external walls was 1.0 from 1975 to
1990, 0.6 from 1990, 0.45 from 1995 and 0.35 from 2002. Yours
may of course be better than the minimum, or just could be worse
if one of the trade-off provisions was used. For places built at
the time the regs changed it's probably wise to assume the
higher figure as the plans were probably approved pre-change.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
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