Leaving asbestos alone

Filon over-roofing saves cost of asbestos disposal in Wrexham

When the existing asbestos cement roof started to fail at Coleg Cambria, Wrexhams’ higher education college, Filon over-roofing was used to refurbish the Engineering Centre of Excellence.

Water ingress, caused by deterioration of the existing roof, was putting high value machinery inside the building at risk. Urgent attention was required, but the asbestos in the roof meant that it would be a potentially time consuming and risky project.

To keep time, cost and risk to a minimum, the contractor opted to use Filon’s GRP over-roofing sheets. These can be used in refurbishment projects without needing to remove and dispose of the original asbestos. Making the refurbishment process much quicker and less disruptive.

As metal roof sheets would be too heavy, the lightweight Filon GRP system was the perfect solution. It added very little to the overall load of the roof and the structural survey proved it worked.

Approximately 3400m2 of Filon’s double reinforced OPDR30E sheet in a light grey coloured 32/1000 trapezoidal profile was used. The opaque sheet uses conventional glass reinforcement with a preformed woven glass matt. This produces a sheet that has greater impact resistance, span and load bearing capabilities than a heavier standard production GRP sheet, without increasing the sheet thickness. Thinner sheets have crisper profile definition for more effective side and end lap sealing, so can be installed much more easily.

Filon over-roofing sheets that match most current and obsolete profiles are available to improve the performance and aesthetics of failing buildings.


On projects like this, where workers are accessing fragile roofs, it’s vital to ensure everyone’s safety. It’s common practice in large asbestos cement-clad buildings to install safety nets to protect against falls, but this wasn’t possible at Coleg Cambria because of internal ceilings, so an alternative was needed.

The solution? A bracket and bar spacer system was installed to create a void between the existing roof and the over-roofing sheets. This allowed ‘sacrificial’ safety nets to be fixed over the existing roof. It also allowed for insulation to be included, which improved the thermal performance of the roof. The relatively low cost of the safety netting, compared with the potential cost of removing and re-fitting the ceilings, made sacrificial netting a very cost-effective solution.

Peace of mind with Fixsafe

The safe replacement system for damaged roof sheets and rooflights

The Fixsafe system allows you to replace roofsheets and rooflights from below, so you don’t need to access dangerous, fragile roofs.

Saves money

Fixsafe minimises access equipment costs, reduces time needed on site and doesn’t risk workers’ safety.

Minimises disruption

The speed, ease and safety of using Fixsafe means that sites can carry on with minimal disturbance to the normal routine.

HSE compliant

Fully compliant with Regulation 9 of the Working at Height Regulations 2005, Fixsafe is an accepted means of allowing those involved in repairing fragile roofs to work safely.

A complete system

Fixsafe is made up of specific GRP replacement sheets to match all popular asbestos and fibre cement profiles, together with fixings to install from below.