By Jason Godfrey, General Manager, Safesite Ltd
Today’s requirement for more sustainable planning and construction has seen an increase in the demand for green roofs with both government and local authorities actively encouraging such developments, particularly in urban areas.
Why are Green Roofs Popular?
The benefits of this technology are substantial. As well as being aesthetically pleasing and a cost effective means of enhancing biodiversity, green roofs also have the benefits of increasing the life expectancy of the roof membrane, protecting it from UV degradation and weather damage, reducing rainwater run off which prevents localised flooding and improving air quality by converting CO2 to oxygen and removing airborne pollutants. Their greater thermal mass also has a positive impact on a building’s energy consumption by improving its thermal performance, reducing fuel costs by insulating and/or cooling the building
So when you take all this into consideration, it’s easy to see why the demand for sustainable construction has grown and we’re seeing an increase in green roofs, particularly in cities where these roofs are seen as an important part of combating the effects of climate change.
Safe Maintenance of Green Roofs
There is however, a common misconception that green roofs are self-sustaining so do not require maintenance. This is not the case, green roofs require maintenance at least twice a year, which according to the HSE is frequent activity. In addition to maintenance of the vegetation such as removing weeds or replacing dead plants, drain outlets and fire breaks must be checked, components such as flashings, mastic and roofing membrane inspected, rooflights cleaned, photovoltaic panels maintained and general rubbish removed from the roof.
It’s essential that these maintenance requirements are planned for at the design stage and, as is legally required, provision made for fall protection systems so that work can be carried out safely. When considering a safety system, the general rule is for collective measures such as guardrails to be the first priority, especially when many of those accessing the roof will have limited experience and training when it comes to working at height. As this photograph shows, guardrails need not detract from the aesthetics of the green roof, powder coating in a colour that blends in with the environment can help to enhance it.
There will be occasions however, such as for technical or design reasons where collective measures are not suitable. In these cases, fall restraint or fall arrest systems such as roof anchors and lifelines provide an ideal solution. Lifelines allow the user continual handsfree protection along the length of the system without the need to detach while roof anchors can be used as a single unit or as a series of anchors linked together via a horizontal lifeline to provide user protection. Whenever possible these systems should be used as fall restraint which prevents the user from reaching the leading edge. If work does need to be carried out in an area where a fall is possible, then fall arrest protection will be required and the user must then have appropriate training on both the equipment and rescue.
Growing Demand for Green Roofs
With demand increasing for environmentally and ecologically friendly construction methods, the popularity of green roofs will undoubtedly grow. As with any form of work at height, safety on green roofs must not be overlooked. By considering safety at the design stage, fall protection systems can be installed before planting, allowing the green roof to grow ‘around’ the system. This makes it less obtrusive but still ensures that the roof and equipment on the roof can be maintained in complete safety