The underfloor heating screed perimeter border / edging or perimeter edge insulation strip is used with screed floors.
The underfloor heating foam border edge strip allows the screed floor to expand and contract with the underfloor heating system. When the underfloor heating heats up the screed floor will expand and contract, the screed perimeter edge strip eliminates all risk of damage to the building through this movement.
The polyethylene foam perimeter edge strip is supplied in two sizes 25 metre & 50 metre roll sizes x 100 mm x 8 mm thick with PVC apron to ensure a good seal is made to eliminate the risk of the warm screed floor being in contact with the cold sub floor.
Screed perimeter border edge strip is usually supplied is blue colour but this may vary.