The builders are now in Church House , knocking down partitions, removing ceilings, chipping out mortar.

What they can't see is behind the walls and for this a Thermal Imaging expert Robert Demaus was called in.

First the equipment must be cooled down to a very low temperature because it works by detecting temperature changes.

Next it was carried into the building and set up ready for action.

Robert explains his procedures to Allen Van der Steen, the architect and the builders.

A visual check is made on an alcove that was thought might have been a window

The Imager will be able to detect any previous opening in the wall.

Robert must now continue all round the room and then move from room to room

Finally he will take all the film back to his laboratory and produce his report for the Church House Management Committee