Your model railway dealer will stock different 1/87 scale imitations of corrugated iron or fibre cement sheet. Nevertheless, Mr. Hans Sack, Germany, had a very nice idea for creative modellers.
you need is a piece of ribbon cable which you will find in most personal
computers (nowadays there will be at least one old discarded PC in every
a sanding block, carefully remove the insulation until the silvry wire strands
appear. Cautiously tear them off.
the remaining insulation ribbon to the size you need (e.g. with a sharp knife
and a metal ruler).
paint or patinate the ribbon sheet.