Unlike the majority of flat roof membranes, Dryseal glass reinforced polyester (GRP) roofing system is a mechanically-fixed component based solution, supplied as a kit of pre-cured parts from the company’s Northamptonshire factory. Thus the vagaries affecting ‘wet lay’ roofing systems are eliminated, facilitating on-site installation time and labour.
Unlike conventional PVC single ply membranes, Dryseal does not suffer from polymer migration during its life; on a timber roof, Dryseal GRP is in excess of 20 times more puncture and load resistant than PVC membrane.
Dryseal achieve Ext F.AC external spread of flame ratings or better under BS 476. It can be manufactured using materials which meet higher levels of fire retardation if the specification requires it. Dryseal achieves the Ext F.AC rating when laid directly onto combustible substrates such as timber, without needing to introduce fire retardant insulation.
Being a semi rigid membrane, it is easier to detail around potential weak spots such as dormer windows, valleys, mansards, bay tops, porches, parapets, troughs, balconies, vertical and curved building edges. Innovatively, it is BBA certified for ‘zero’ falls (1:60). It can also be used to form green roofs, without the need for a fleece underlay or root barrier. As it does not leech, it is also safe to use with grey and potable water schemes. It can be used to form new cold and warm roofs, and in refurbishments, where it can be fixed without necessarily stripping off the existing covering.
Beyond its practicalities as a material, it is eco-friendly. Its ability to accommodate rigid PI insulation as part of a warm roof construction can help deliver higher-than-average thermal efficiency: U values of 0.12W/m2K, compliant with Green Deal, can be attained. All component parts can be recycled. With regard to embodied CO2, Dryseal has a rating of 6, PVC generates almost three times more, and bituminous membrane six times more.
Dryseal Manager Andy Fell said “Dryseal is a win: win for housing associations. It can help achieve energy efficient homes. It is able to withstand some fairly heavy treatment whilst being quick and easy to install and durable – it is guaranteed watertight for 20 years.
“Housing Associations are under pressure to cut costs after the 2015 Maximum Fair Rent rule changes, but also need to build to meet the proven need for social housing. Indeed, latest figures from the Office for National Statistics show a growth of more than 10% in social housing new build. Using our Approved Contractors, housing associations can confidently specify Dryseal, knowing one product can be used in a vast range of applications, new build and refurbishment. That saves time and effort developing specifications and tenders, and then on-site.”