Richard wrote:

Problem: the house is built from a type of white brick which is very
hard and shatters given half a chance.

I presume that these: http://tinyurl.com/ywx855 hardwall picture hooks
- described as not suitable for plastered walls - cannot be used.

I use those on ('50s hard) plaster all the time and find them very good.
You can also remove them with little damage just with a few gentle taps
on the side with a small hammer.

The quick answer is invest in a bag of them and try. (Screwfix do a
couple of different sizes)

--
Cheers,

John.

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