Cambridge Flat Roofing – Single Membrane System
The Single Membrane or ‘Single Ply’ System, how it works and what you should be aware of.
Whenever you invest in renovation work, you would be wise to research all the possibilities and the questions, problems and pitfalls you may encounter before you make your final decision. It would always be wise for you to make sure that any system you use has been tested and certified by the BBA and that it can back up its performance claims, and you should also work to make sure you have at least a basic understanding of the different options that you will be presented with.
The basic premise of the single membrane system is that in place of the multiple layers of mineral felts or asphalts formerly used in flat roof construction, a single ply sheet of waterproofing membrane constructed from a combination of manmade synthetic materials is used instead. This membrane has a significant advantage over the traditional approach in that it is impervious to the elements and will weather year on year without tearing or becoming warped. It will also be resistant to mould and moss growth, it is breathable and so prevents moisture becoming trapped in the layers below and is solar reflective, so you won’t have to worry about chipping blowing into your guttering.
Different types of installation system may be mechanically fastened or fully bonded and although both have their advantages and disadvantages, they are both best applied under fairly individual circumstances. Mechanically fastened roofs are best used where the substrate deck is made out of timber, whereas fully bonded roofs are better where the substrate is made of either concrete of wood wool slabs. It’s equally important for you to be aware that the fully bonded system should never be installed in temperatures below 5 degrees and as such it would be wise for you to wait for warmer weather before you begin your renovation project.
The joins may also present you with a choice that you would do well to be informed about. You may well be asked to choose between heat welded joins and glued joins and if you aren’t, we would certainly advise you to ask the question. Glued joins are secured using tape or adhesive both of which can be vulnerable to changing temperature and moisture levels. Welded joins, using a heat gun, have no such vulnerabilities and are stronger and more durable than any other alternative.