1201XL | Telescopic Underfloor Vent 5-7 Courses

• Telescopic and adjustable for a step of 5, 6 or 7 brick courses.
• Suited for 50-150mm cavity width construction.
• Horizontal and vertical extension accessories available.
• Free area of 8000mm2 per unit when installed without airbrick.
• Free area of 6500mm2 per unit when installed with 1201AB airbrick.
• Equivalent area of 6170mm2 per unit when installed with 1201AB airbrick.
• Special grille included to prevent entry of vermin.
• Durable, robust and totally resistant to decay.

• Satisfies all NHBC requirements.
• Manufactured to BS EN ISO 9001 and BS EN ISO 14001.
• Complies with all relevant Building Regulations.
• Meets all relevant British Standards.

• Manufactured by injection moulding in polypropylene.
• Available in black only.

F30 Accessories/sundry items for brick/block/stone walling

Clause 160 | AIR BRICK

• To BS493, Class 1, built in as the work proceeds.
• Manufacturer: Timloc Building Products, Timloc House, Ozone Park, Howden, East Yorkshire, DN14 7SD. T: 01405 765567, W: www.timloc. co.uk
• Reference: 1201XL Telescopic Underfloor Ventilator
• Design: Rectangular
• Work size: Each unit 375/525mm coursing x 220mm
• Material: Polypropylene
• Colour: Black
• Optional Accessories:
  • 1203 Horizontal Front Extension (+115mm)
  • 1204 Vertical Extension Sleeve (additional 2 brick courses)
  • 1205 Duct Adaptor (suits 110mm diameter duct)
  • 1206 Horizontal Rear Extension (+100mm)

• Always use in conjunction with a Timloc airbrick.
• The airbrick and upper front opening of the telescopic underfloor ventilator must be positioned above the finished external ground level – usually at the same level as the ground level DPC
• The lower rear opening of the product must project down to the level of the underfloor void and must not be obstructed by the floor construction. A vertical extension sleeve is available to fit with this product if the standard 7 course step is not adequate.
• Building Regulations require a free airflow below suspended ground floors of at least 1500mm2 per metre run of wall. This can be achieved by spacing the ventilators at 4m centres, however, such a wide spacing is not recommended as stagnant air pockets could form in the underfloor void. Timloc recommend a spacing of not more than 2m centres to comply with NHBC standards.
• The NHBC recommend that underfloor ventilators are spaced at a maximum of 2m centres, with ventilators also positioned not more than 450mm from the ends of the wall.
• As a minimum requirement, ventilators should be positioned down two opposite sides of the building so as to create a cross flow ventilation action. It is good practice to position ventilators around the full perimeter of the building, particularly with complex building designs.
• If the underfloor void is separated by dividing walls, openings must be provided to allow a free flow of air around the underfloor void.
• The standard ventilator will fit into a cavity wall with an external leaf of 100-102.5mm, a minimum cavity width of 50mm and across a cavity of 150mm. External and internal horizontal extension sleeves are available to accommodate thicker walls or wider cavities.
• To be installed with a DPC Cavity tray and wall weeps to collect any water ingress. We recommend Timloc’s IL4 and 2 weeps (Invisiweep or 1143 Cavity Wall Weep Vent).
• When incorporating with a gas barrier system and adjusted to the required height, the joining sections should be sealed with proprietary tape.
• It may be a requirement to protect with a lintel for direct loads.

N.B. The 1201XL is designed for use with a 1201AB airbrick. It can be used with a clay airbrick but this will reduce the overall airflow.

• Measure the length of each wall requiring telescopic underfloor ventilators and divide by 2m to establish the quantity required.
• Always round up if the calculation does not work out to an exact whole number.
• To be installed with a DPC cavity tray and wall weeps to collect any water ingress. We recommend Timloc’s IL4 and 2 weeps (Invisiweep or 1143).

• 1201XL telescopic underfloor ventilator.
• Matching airbrick and a range of accessories (available separately).