The extreme cold of the past two winters has a hidden implication for housing providers- the risk of increased, damaging condensation in the roofspace. A new white paper proposes the safe, secure way to address the issue before next winter strikes.
Published by Glidevale
, the UK’s leading supplier of roof ventilation solutions, the white paper examines the growing trend towards the use of internally installed roof underlay lap ventilators, and advises specifiers to check compliance with Building Regulations and Standards regarding roofspace ventilation requirements, and for practical implications arising during installation. It also offers considerations to ensure the roofspace is effectively- and safely-ventilated, to eliminate the risk of harmful condensation, such as fitting of specifically-designed, through-roof ventilators.
Nick Beswick, Glidevale
Sales Director, elaborates, “Preventing harmful condensation with roofspace ventilation has historically been a major consideration in housing specification, but one somewhat forgotten as our climate has been more temperate for a few years. The severity of 2009 and 2010 winters has seen a significant increase in incidence of roofspace condensation, and prompted a ‘knee-jerk’ reaction, in some instances.
“Internally fitted ventilators have found a niche because they do not need contractors to work on the roof, they can be fitted from within the loftspace. However, that means the contractor is still at risk, balancing on joists to avoid falling through the ceiling, joists which could be hidden under the insulation, or crawling into the tight eaves space or reaching at full stretch to higher underlay overlaps.
“And even once installed, research shows that the ventilators do NOT deliver adequate ventilation, and increase the risk of tiles lifting under wind loading. Testing shows that a typical single course of interlocking tiles including internally fitted ventilators can only provide 3000mm2/m free ventilation area; Building Regulations require over three times that amount (10,000mm2/m). Also, certain types of these ‘ventilators’ in effect create holes in the underlay, stopping it acting as a wind deflector and allowing both the weather and potentially birds, vermin and insects into the loftspace!”
slate and tile ventilators are purpose-designed to ventilate through the roof slope and form an integral part of the roof covering, whether new build or refurbishment/retrofit, without adverse impact on its performance. They are supplied with an underlay opening protector, integral 4mm insect screen and throat or extension sleeve to meet all the design requirements of BS5250
. In addition, they are deluge and driving rain resistant, and the only ventilators of their type to carry AA fire rating enabling unrestricted use. Uniquely, Glidevale
offers a site survey service to give property managers a detailed review of what type and quantity of ventilation products, if any, are required for individual properties.