Description
First of all the dual extended telescopic vent designed to provide a clear airflow passage to a void beneath an insulated suspended floor. (8,000mm² airflow) Furthermore the current and future requirements of Part L of the Building Regulations along with other standards and regulations have led to an increase in the depth of thermal insulation in suspended floors. Along with an increase in cavity widths to accommodate greater amounts of cavity wall insulation. Consequently this has meant that clear access to an underfloor void may be as far as 6 or 7 brick courses (525mm) below the level of an airbrick. And potentially as much as 350mm from the outer face of the external leaf. Traditional telescopic underfloor ventilators would not be able to achieve this without the use of additional vertical and horizontal extension sleeves. Furthermore the dual extended underfloor vent offers vertical telescopic adjustment of between 5 and 8 brick courses (318mm-575mm) without the need for an extension sleeve. Ensure the horizontal outlet is long enough to bridge through an overall wall thickness of 350mm without the need for an additional extension. Finally the front aperture is designed for use with a combination airbrick or it can be used in conjunction with a traditional clay airbrick. Although this would reduce the overall airflow through the system.
Regulations – BRE Digest 17, BRE Digest 262, Building Regulations C4, NHBC Standards 5.2 and BS 5250:2011 Control of Condensation in Building
Installation
1. Should be installed during the normal course of bricklaying.
2. Can be fitted as an assembled unit, or with the base component positioned first
with the top added later when the bricklaying reaches the correct height.
3. If fitted above the DPC then a suitable cavity tray should be fitted above the vent.
4. Should be fitted in at least two opposing walls to create a through flow of
ventilation into an underfloor void.
5. Should be placed at not more than two metre centres and within 450mm of each
end of the wall.
6. Bricklaying should then be completed as normal although care should be taken to
keep the airflow passage clear from mortar droppings.
7. Should be used in conjunction with an airbrick, and possibly an extension sleeve.
8. Extensions that require fewer than a 5 course drop in the brickwork can be achieved by trimming
the required amount from the vent.
