SIKA SARNAFIL SPECIFIED FOR NEWNHAM COLLEGE, CAMBRIDGEThe Principal’s Lodge at Newnham, one of the 31 colleges at the University of Cambridge has received a major upgrade of its existing corrugated aluminium roof in order to improve installation properties and aesthetics.

The new roof now includes 500sq m of SikaSarnafil single ply roofing system, installed by leading flat roof specialist and contractor Cambridge Polymer Roofing.

To ensure that disruption to staff and students was kept to a minimum, Buildings Manager at Newnham College worked closely with main contractor Cambridge Polymer Roofing to manage the project appropriately.

The original roof was not in character with the nature of the dwelling; it was virtually un-insulated and was an industrial style aluminium roof so at the client’s request, Cambridge Polymer Roofing installed a SikaSarnafil G410-18ELF single ply membrane in Light Grey. This is an adhered system, which also incorporated Décor Profiles to imitate a standing seam roof.

The specification required attachment of the new roofing system to the existing metal deck, which meant additional fixings were installed to ensure the deck was secure prior to the SarnaTherm installation being mechanically fastened on top. As the profiled deck was aluminium – soft metal – normal fasteners could not be used and special fixings, called peel rivets, which are normally used with problem decks, were utilised instead.

Once the insulation was attached the SikaSarnafil membrane was then installed to give a waterproof finish and completely encapsulate the existing roof.

A number of challenges arose during installation. “The greatest difficulty was in changing the profiled aluminium details to SikaSarnafil details and still maintaining the aesthetics. Additionally, the low pull out strengths of the aluminium deck necessitated alternative fixings by way of the peel rivets,” Cambridge Polymer Roofing’s Steve Wale said.

“Nothing was an issue for us although it is a slightly strange design having an inverted elevation. Despite this unusual roof design, the team on the project showed a professional approach and carried out the project with no glitches,” Newnham College’s Andy Kite stated.

The project was successfully completed to the client’s satisfaction, on time and budget.

“The finished product looks very good and the client was extremely happy with the outcome. The roof building is visible from adjacent blocks so the visual impact is significant which meant the need for the aesthetics was essential,” Steve added.

“The team at Cambridge Polymer Roofing were great to work with and I would definitely recommend them to other clients,” Andy said.