Stockport, United Kingdom


A popular primary school with around 1000 children on roll, Didsbury Road School in Stockport is a large single storey building located within a conservation area.

The building’s flat roof features large glazed areas along with a small number of traditional roof lights. Both the roof covering and the glazed areas were in a poor state of repair: large areas of the existing felt roof covering had delaminated. Meanwhile, some of the glazing was broken, allowing vegetation to grow through the roof, and there was water ingress in a number of locations.

To address these issues, a roof refurbishment was carried out using Sika Liquid Plastics’ Decothane Ultra cold-applied liquid roofing system. The project has transformed the building and was shortlisted in the Liquid Applied Roofing Systems category in the 2019 National Federation of Roofing Contractors (NFRC) Awards.

Flat Roof Project Requirements

The refurbishment required a complete strip out of the existing roof covering and glazing. The strip out could be carried out during the summer holidays but much of new roof installation had to be carried out during term time, so it was important to specify a system that would minimise disruption for staff and students. As a result, Sika Liquid Plastics’ low-odour Decothane Ultra provided the ideal cold-applied liquid solution with no nuisance odours to disturb lessons.

As there was very little insulation on the existing roof, upgrading the building’s thermal performance with a warm roof build up to meet current building regulations was also essential. In addition, the insulation upgrade provided an opportunity to create falls in the flat roof to aid drainage.


Sika Liquid Roofing Solutions

Following a site audit and condition survey by Sika Liquid Plastics’ Technical Area Manager, a technical specification was drawn up for the project and Sika Liquid Plastics national award winning quality assured QA Contractor, Permicoat Ltd.

The Permicoat Ltd team stripped the roof back to the metal substrate and removed the existing glazing before applying Sika Liquid Plastics’ Primer 600 and installing S-Vap 5000 air and vapour control layer (AVCL).

Both flat and tapered 130mm Decotherm insulation was then installed onto the prepared roof surface, followed by another coat of Primer 600 and S-Vap 5000.

The low-odour Decothane Ultra cold-applied liquid roofing system was then applied to the whole roof area, including the parapet walls and the newly formed gutters.

Permicoat also replaced all the traditional Georgian roof lights and were assisted by Cheadle glass to replace the 80m long glazed panels along with a small number of which were specified to meet the restrictions of the conservation area location.

"There was no alternative but to fully strip off all the existing roof coverings before the new Decothane Ultra BUR system was installed providing the ideal solution for creating an entirely new roof build up within a programme of just 15 weeks. The low-odour, cold-applied system enabled the school to operate on a business-as-usual basis during the project and will provide a durable solution for at least 20 years. Decothane Ultra provides an ideal solution for operational school refurbishments and, with the addition of tapered insulation and new guttering, the new roof will provide robust protection against the elements." Phil Purcer, Managing Director from Permicoat

Products Used

Sika® Liquid Plastics Decothane Ultra

Sika® Liquid Plastics Primer 600

S-Vap 5000 air

Vapour Control Layer


Project Participants

Specialist Contractor
Permicoat Ltd

Sika Organization

Sika Liquid Plastics

Roofing Client
Stockport Council