On 10/03/2020 14:25, Bert Coules wrote:
Andy Bennet wrote:

An IR camera works - different thermal characteristics of the morter v
the blocks.

Thanks very much for that.Â* Am I right in thinking that it would be
necessary to remove any obstacles such as shelves, empty bookcases and
the like away from the wall to get a meaningful result?


Yes you will, as all those other items will just clutter the picture
with there own signature - I assume the point of interest is behind
those?. Obviously wallpaper is ok as it is thermally homogeneous.