Specifier Review


Liquid waterproofing specialist, Kemper System, has launched KEMPERGRO, the company’s first ever complete green roof system.




Suitable for use in both newbuild and refurbishment projects, KEMPERGRO has been designed to enable specifiers to source a complete green roof from a single supplier and builds on Kemper System’s existing track record in the green roof sector.  Kemper System’s KEMPEROL wet-on-wet liquid waterproofing membranes, including the environmentally-friendly solvent-free KEMPEROL 2K-PUR system, offer root resistance and a service life in excess of 25 years, making them an ideal base for green roofs and a common specification beneath externally sourced green roof systems.


KEMPERGRO is a three section green roof system comprising a reservoir attenuation composite, growing medium and vegetation. The reservoir attenuation layer includes an upper filter fleece, central reservoir core and lower protection fleece all of which are manufactured using over 90% recycled materials which helps to enhance the green roof’s environmental credentials. All three components are factory bonded to maximise performance and simplify installation, preventing sagging under the weight of the growing medium to maintain reservoir capacity and prevent blockages.



The growing medium is 100% composed of recycled brick, tiles and green compost and is processed and graded to support an extensive range of sedum, meadow and lawn roof media, all of which are grown and sourced in the UK.  Whether the requirements are for sedum matting, plug plants or seeds, Kemper System can provide a solution to meet local climatic conditions, aspect, biodiversity and specifier preference and the company can advise on the most appropriate growing medium to match the specific needs of individual projects.


In addition to providing a natural, living roof environment created using recycled materials, the KEMPERGRO system also helps to enhance the environmental profile of refurbishment projects by enabling installation on top of the existing substrate.  This ensures that strip out and removal of existing roof materials to landfill can be avoided. For refurbishment installations, Kemper System’s hard top insulation board can often be bonded directly to the existing substrate, using the existing waterproofing as the vapour control layer. This is followed by KEMPEROL waterproofing, the attenuation layer, the growing medium and finally the sedum or vegetation.



Harry Cowell, managing director of Kemper System comments: “Green roofs are amongst the most popular ‘eco’ features in contemporary building projects but ensuring that this type of living roof thrives, enhances the building and has no detrimental effects on structural integrity is a complex undertaking. Kemper System’s track record in sustainable and environmentally-friendly products, along with our roofing expertise and substrate conservation means that specifiers can be completely confident of a high quality end result with KEMPERGRO while rationalising their supply chain.”