Poulton Lancelyn Community Primary School in the town of Bebington on the Wirral is part of the Oak Trees Multi Academy Trust. The school is based in two buildings on a single campus, with foundation stage and key stage one pupils in the infant block and key stage two students located in the junior block. Both single-storey buildings had significant issues with water ingress and were in need of improvements to their thermal performance to bring them into line with current building regulations.

Poulton Lancelyn Community Primary School was eligible to apply for government funding and the school worked closely with partnering surveyor, E3 Cube, and Sika Liquid Plastics’ to develop a business case for the project to support their bid.

The roof of the infant block was in very poor condition, with a badly degraded felt covering and standing water caused by poor drainage. To address this, the project called for a strip out of the existing roof and installation of a warm roof system with tapered insulation. While the existing felt roof of the junior block had also reached the end of its service life, this building could be refurbished as a warm roof overlay.

Refurbishment of both roofs also required replacement of the existing roof lights.


As the work had to take place in a live school environment over the winter months, use of a low odour liquid system that offered speed and ease of installation was essential to reduce disruption and minimise the programme. The school was also keen to ensure that the selected system would offer an extended service life and excellent performance.

Sikas’ Area Technical Manager carried out a condition survey on the roofs and worked closely with E3 Cube to develop a full technical specification that would both resolve the issues and ensure the ponding water did not recur. Sika Certified Roofing Contractor, Mars Construct Ltd, was awarded the contract to carry out the roof refurbishment.

The infant block roof was stripped back to the substrate and 270mm Decotherm insulation was installed, tapering to 120mm to create falls for drainage. The 53 existing roof lights were removed as part of the strip out and Decolight roof lights were custom-fabricated to replace them in the existing apertures. The Decothane Ultra, 25-year, virtually-odourless cold-applied liquid system was then applied onto the Decotherm board. The roof was finished with a maintenance walkway in a contrasting colour.

For the junior block, the Decothane warm roof system was installed as an overlay. Decotherm 130mm insulation board was installed onto the prepared felt surface and the 10 existing roof lights were removed and replaced in the original apertures with custom-fabricated Decolight units. The Decothane Ultra system was then installed across the roof.

"This was a challenging project due to the need to carry out the works in a live school environment during the winter months. However, the use the virtually odour-free Decothane Ultra system from Sika Liquid Plastics enabled us to minimise disruption." Craig Difiori, Mars Construct