Sika Liquid Plastics’ Decothane cold applied liquid membrane has been used to overlay a 1000m2 police custody suite at Paisley Police’s divisional headquarters.


Originally constructed in 1964 as part of a mixed development that includes the police headquarters, Renfrewshire Council offices and the District Court, the single storey building contains police cells and accommodation for officers.


The building was partially overlaid using Sika’s Decothane liquid system when polyurethane membranes were in their infancy 30 years ago, and the previous Decothane surface was still intact.  However, two thirds of the roof still had an asphalt surface and, as this was failing, the decision was taken to overlay the entire 1000m2 roof with Decothane 20-year single point guarantee system in slate grey.  

Decothane was specified by the scheme’s architect, Kenneth MacNaught, as a cold-applied liquid system that requires no hot works, providing an ideal solution for a building in which full occupation and security are business critical.


Roofing contractor, MMPS Scotland Ltd, prepared the roof by power washing both the asphalt and Decothane surfaces and carrying out patch repairs on the asphalt to create an even surface. An appropriate Sika primer was then applied to each area and allowed to cure overnight before the Decothane system was applied to each area of the roof surface.


The red Decothane resin base coat was applied to each section of the roof using rollers and allowed to cure before the installation team applied the grey top coat.  The change in colour between the two coats ensured that the MMPS team could see instantly when sufficient resin had been applied to obscure the red base layer.  

This visual check delivers the 20 year guarantee to ensure the police station would be sound for years to come, as the works were checked on a weekly basis during progress by the Sika Liquid Plastics technical team, to ensure correct application of the system, leading to a full 34 point Final Inspection sign-off.


The project also involved construction of a new raised concrete area on the roof to accommodate new plant and MMPS used the Decothane system to encapsulate the upstands, lifting each piece of plant to install the roofing system in phases across the rooftop plant area to ensure a completely watertight finish.

To complete the installation, MMPS created non-slip maintenance team walkways by applying an additional layer of green Decothane top coat with fine sand and sealant around the plant roof and access areas.


Jim Killen from MMPS, said: “We have been using the Decothane system for around 12 years and were impressed to find that the Decothane surface laid onto this roof 30 years ago was still performing well.


“As a low odour system that requires no hot works, Decothane was the ideal solution for this building and, as always, the technical support we received from Sika was second to none.”

Danny Quinn, Senior Area Sales Manager

"Decothane has been used on many police station and custody suite projects in Scotland because of its excellent service life and ease of application.


“We’re delighted but not surprised that the existing Decothane at Paisley divisional HQ’s custody suite was still intact and, following the overlay project, the whole building can now expect to remain leak free for decades to come.”