"R D S" wrote in message
...
I know of a building which has been gutted by fire, stone and brick
construction.

It was empty for ages before the fire and I had my eye on it coming up for
sale as it would be perfect for my needs.

Most buildings in this state seem to end up demolished, it would need new
floors and a roof but other than that is there any reason why it couldn't
be usable?

Heat can reduce the mortar strength to the extent the walls can collapse.
You need to get it checked to see if the walls are salvageable.