Derby Magistrates' Court
The internal plasterwork to one of the courtrooms at the grade II listed Derby Magistrates Court was failing. The plaster was coming away from the wall in large sections and evidence of damp was apparent.
All the plaster along the 9m long wall was removed along with the decorative picture rail. A mortar analysis was taken and this showed that a large percentage of the plaster was a modern renovating type plaster and this was trapping damp in the wall. The wall in question was once an external one and was probably replastered when a large extension to the courtroom took place. Small amounts of the original lime plaster were in evidence however. The wall was prepared by dubbing out with lime mortar all the larger holes and recesses. Vertical screeds were then formed on the wall and plumbed to make the wall level.
A base coat of lime putty, sharp sand and goat hair was then placed and allowed sufficient time to dry. A levelling coat of the same mix minus the goat hair was then placed between the screeds and ruled level to give a flat and plumb wall.
A new moulded picture rail was then fixed to the wall matching exactly the original before the wall was given its finishing coat comprising lime putty and silver sand. This was then decorated with a suitable paint.