Traditional built up felting used to weather flat roofs has been around for many years & served commercial & domestic flat roofing extremely well. With the other types of membranes now on the market e.g., EPDM rubber roofing & GRP glass fibre roofing, many people feel that because they are new technology, they are better than traditional felt roofing, and have asked are these replacements for built up felting.
But at Brian Parker Services with our 40 years plus experience as a flat roof contractor Wokingham, we feel they are just new options & will undoubtedly cost you more money to fit and maintain in the short and long term.
Allow me to explain:
The guarantees from the manufacturers on these two new membranes are no more than traditional felting, even that given by the contractors!
Built up felting comes in two different types APP & SBS. All APP felt will tear in your hands with little or no effort & is more likely found covering the garden shed.
SBS felt on the other hand won’t, in fact a very sharp blade is required to cut it, it is pretty tough & almost puncture proof unlike rubber EPDM roofs & indeed GRP glass fibre!
We found contractors within the industry will charge you for SBS felts & then fit an inferior APP felt, a contractor fitting APP felts on a flat roof will provide your flat roof with inferior felts that will tear due to expansion/contraction & only last around 10-15 years maximum.
If high performance SBS felts are used & correctly fitted, then the life span will easily increase to a minimum of 20-30 years.
Even within the realms of SBS felts there’s low end felts & high ends felts! Talking to your contractor about these felting options is vital so he knows that you are serious and asking the right questions.
The standard guarantee period we as a company provide on these type of SBS felt covered roofs is a minimum of 15 years, but we know they will last 20-30 years depending if over hanging trees are nearby and how much exposure there is to the elements.
If I may before I finish point out & advise that both EPDM rubber roofing needs to be stuck down to clean decking boards, to achieve this new decking boards will be required along with the increase cost of materials/labour & possibly waste disposal of the old decking.
This merely enables the contractor to completely stick the rubber roof to the decking timbers. GRP glass fibre roofing is the same, in fact it requires tongue & groove boards to be fitted over the existing decking boards.
With these two new membranes available replacing them in the future will be extremely costly as they are completely stuck down! Where traditional built up felting done well will cost you a lot less and last you almost as long as the new options and isn’t stuck down to the decking boards.
As I write GRP membranes still haven’t achieved the BBA agreement standards recognised in the UK but we’re assured there working towards getting it.
SBS felting has all it’s BBA approval but will require full public liability insurance for the use of heat to install it & that is why some roofing contractors are changing to the new alternatives as they don’t require full heat cover, however, both EPDM rubber roofing & GRP glass fibre both use chemicals that are highly flammable, so cover yourself and check there are adequately insured. Brian Parker Services ARE fully insured for the use of heat.
We do offer the option to all our customers of having any one of the above membranes fitted to your home. but we felt it needed to be explained as felting was being branded as the poorer option which is most definitely NOT the case.