venting a view on re-roofing

Over 1.5m homes in the UK are rented from registered social landlords- an increase of 250% over the past 25 years! Further, statistics* show that over 70% of homes were built before 1984, meaning they require remedial work to ensure they are remain warm and weatherproof- including the roof fabric. Glidevale Ltd, one of the UK’s leading suppliers of roofing solutions, has developed an innovative range which enables cost-effective re-roofing to Regulatory requirements, and which provides cost and labour savings, both for the specific project and in long-term maintenance.

BS5250 is now the main means of complying with Building Regulation requirements and is good practice in re-roofing. The Standard recommends the combined use of a vapour permeable (type LR) roof underlay and high level ventilation to combat the risk of harmful roofspace condensation in cold-pitched roofs.

In older properties, air leakage through ceilings transfers more moisture into the roof by convection than passes through the ceiling materials by diffusion, so simultaneously should be addressed to optimise the roof performance. Figures from the Building Research Establishment have shown that 50% of vapour transfer from the warm home to the cold loftspace occurs around the loft hatch cover, especially if the hatch is a conventional unsealed version.

Glidevale’s combination of Protect VP400 vapour permeable underlay, Rediroll ridge ventilation system and high performance loft traps combine to ensure a dry, properly ventilated roofspace is achieved, particularly in re-roofing/ roof upgrade programmes, where the ceiling is unlikely to be ‘well-sealed’.

Glidevale’s Protect VP400 is highly vapour permeable but entirely watertight. It is strong and lightweight for ease of handling and easy to cut yet is fully UV and heat resistant and tough and durable. Protect VP400 carries certification for unrestricted use with regard to wind uplift, regardless of geographical location within the UK.

Glidevale Rediroll universal dry fix ventilated ridge and hip system’s all aluminium construction makes it rot proof and corrosion resistant, helping it overcome the durability and weathering problems associated with other fabric based roll ridge systems. Its innovative design incorporates integral ventilation inlets to ensure adequate throughflow of air along the ridge and hip, yet resists penetration by driving rain. Rediroll is quicker to install than alternative ridge ventilation systems, eliminating issues of the quality of workmanship in using mortar, and can be fitted regardless of weather conditions whilst the work is undertaken. Rediroll provides a maintenance free solution, removing the need for future re-pointing or re-bedding of the ridge tiles, optimising effective use of budgets.

Glidevale loft traps not only meet the air leakage requirements of BS5250, but also the minimum U value requirements of Building Regulations of Part L: LA1, LA2, LA5 and LA6 loft traps, when specified with rigid insulation, all achieve a U value of 0.35W/m2K.

Details of the entire Glidevale range, including the full ambit of Protect building membranes, roofspace ventilation, and Sunscoop tubular rooflights are available on the company’s website www.glidevale.com. Glidevale specialises in developing and bringing to market innovative yet practical roofing and ventilation solutions to changing requirements.
ENDS
*Survey of English Housing, Office of the Deputy Prime Minister