A roofer came into the yard on New Road last week with a re-roof on a semi off the High Road in Ilford, wanting to know why his usual breather membrane kept failing building control on the vapour check. It’s a fair question, and one that’s had a timely answer this month: the Proctor Group, one of the bigger names in membrane manufacture, has just supplied product free of charge to a modular housing project run by the homelessness charity Social Bite, and the spec they went with is worth any trade or self-builder round Rainham, Romford or Dagenham taking a look at.
The units are cross laminated timber panels built offsite, which sounds a world away from a Victorian terrace on Wangey Road, but the membrane principles are exactly the same ones we sell across the counter every day. A breather membrane still needs to shed bulk water while letting vapour out from the roof void, and with CLT panels that’s arguably more important, not less, because there’s no traditional loft space to dilute any moisture build-up. Get the lap wrong — anything under 150mm on the horizontal — and you’re inviting condensation into the timber.
For anyone doing a cold roof conversion in Hornchurch or Upminster, the lesson from this job is about consistency of detailing rather than any single clever product. Counter battens at the right gauge, a proper vapour control layer taped at every junction, and breather membrane dressed correctly into the verge rather than just draped over it — that’s what got this build past its own regulatory checks, and it’s exactly what we tell customers at the trade counter when they’re stood there with a roll of felt wondering if it’ll do.
It’s also a reminder that offsite and modular construction is creeping into general house building faster than a lot of tradesmen in Essex and East London might expect. A garden room extension, a granny annexe, a full self-build plot in Elm Park — more of what comes through our doors now starts life as a factory-built panel, and the roofing detail still has to be right on site regardless of how the walls arrived.
If you’re speccing a re-roof or an extension anywhere from Barking to Eastham and want a straight answer on which membrane, batten gauge or lead code to use, call in and see us at RTB Roofing Supplies on the Rainham Road — we stock what the trade actually asks for, not just what’s cheapest to shift. More on rtbrs.co.uk/.