Tread Lightly - Guide to Working on Fragile Roofs (Part Two)

Tread Lightly - Guide to Working on Fragile Roofs (Part Two)

07th August 2015

Last week, in part one of our Tread Lightly blog post, we took a look at working on fragile roofs and some innovative new methods of repair and state of the art roof coatings that will mean that roofs on new buildings last longer and need less maintenance. However, all of the existing roofs here in the UK have not been fabricated from high tech materials and an awful lot of the roof work done in the construction industry is likely to be maintenance or refurbishment work on traditional roofs.

Weather always takes its toll on the exterior of buildings and, here in the UK, there will always be roofs in dire need of attention at the end of every harsh winter. Some of the worst roofs to work on are made from asbestos cement (AC) panels. When first installed, the combination of Portland cement and 10% asbestos offered a strong and flexible composite. However, years of weather exposure leaches out the cement and, as time goes by, the roof becomes more and more brittle.

Today we’re looking at some of the measures you can take to stay safe when working at height on a roof. The Advisory Committee for Roofsafety (ACR) is a UK organisation that’s committe4d to making work on roofs safer. It was originally established by the Health and Safety Executive (HSE) in 1999 to look at the issue of fragility in Roofing Assemblies. The ACR has published some guidelines to follow when working on fragile roofs and other fragile surfaces.

  • If at all possible, work from below, rather than on the roof.
  • If you do need to work on the roof, then prioritise non-contact methods such as using a mobile elevated work platform (MEWP) or a scaffolding gantry – never improvise by using forklifts or extension ladders.
  • If the surface is fragile only in specific, clearly defined areas (such as skylights), cover them with loadbearing mesh or sheeting. Use non-contact or work restraint systems to set these covers in place.
  • If you do have to walk onto the surface, use a load-spreading system (crawl boards) but only if the surface has been proven to be strong enough.
  • If there is any possibility that a worker will fall or step off the platform, you will need to provide a fall protection system of some sort. This would typically be a fall arrest net or a soft landing device (such as an airbag) below the surface.
  • Use edge protection for any work areas within two metres of the edge, including on either side of the point of access.
  • Personal protective equipment (PPE) has a limited role in this type of situation. With careful planning, a restraint system can prevent a worker from stepping off the platform, but a fall arrest lanyard is not an appropriate solution. Even if you do find a suitable anchor point, a normal lanyard’s webbing or rope could be severed by a sharp edge during a roof collapse. Besides a worker would experience severe injuries just by passing through the surface.