"Dave Plowman (News)" wrote in message
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In article ,
Steve wrote:
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I've noticed there are small gaps, around a millimetre, at the edges of
some tiles - the mortar has separated from the tile edges. They may
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Cement mortar is a poor material for ridge tiles - as the roof always
moves relative to them. And the stronger you make it the worse the
problem. Use a good non setting mastic to fill any gaps. If doing again
use lime mortar.

Thank Dave. Can you suggest a source for non setting mastic? I can't see
any on Screwfix or Toolstation.