3,000mm² airflow per vent.
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Outdoor Aluminum Pergola Gazebo – Adjustable Roof Pavilion for Garden or Terrace
Aliexpress UK
If further ventilation is required, install one lap vent into every rafter space at low level and/or into lap joints at higher levels. The lap vents should be fitted to both sides of the roof space in order to provide cross-flow ventilation.
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Aluminum carport parking shed metal car canopy with polycarbonate arched roof
Aliexpress UK
Consideration must be given to increased risk of wind uplift and driving rain resistance outlined in BS5534:2014. Discrete profile design.
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3mx4m Waterproof Aluminum Pergola Gazebo with Adjustable Louvre Roof
Aliexpress UK
Cromar - Vent 3 - Blue - 1m x 50m High Performance. It is equally suitable whether draped unsupported over rafters, laid directly over insulation. Technical Information SIZES CUT TO SIZE BUY WHAT YOU NEED NO WASTE /FANTASTIC SERVICES.
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5x6m Aluminum Pergola with Retractable Roller Blind Waterproof Outdoor Arbour for Balcony Garden Cover Roof Motorized Pergolas
Aliexpress UK
Felt Vents for Loft: Each unit will provide 3000mm² of free airflow into the loft space. Lap Vents for Loft: Can be fitted at joist centres ranging from 400mm to 600mm, suitable for most roofs.
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Aluminum Gazebo with Sliding Glass Doors and Motorized Louvered Roof – Ideal for Villa Garden, Balcony, or Poolside Shade
Aliexpress UK
BBA Certified. Vent3 Classic is a breathable roof underlay for cold and warm roof applications which give major benefits over traditional roof underlays. Cold & warm roof application. Light grey surface prohibits glare.
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Door Canopy Awning Shelter Front Back Porch Outdoor Shade Patio Roof Rain Cover 120*80cm
Aliexpress UK
10 x Felt Lap Vent Loft Attic And Roof Ventilation Airflow Lap Joints
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Roof Mounted Bio Ethanol Suspended Fireplace Cocoon Hanging Floating Fireplace
Aliexpress UK
It's a practical addition, especially when coupled with increased loft insulation. Ensure lap vents are fitted on both sides of the roof space for optimal cross-flow ventilation. Install one lap vent into every alternate rafter space at a low level.
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Outdoor Glass House Sunroom Roof Panels Aluminium Veranda for Garden Patio Balcony sunroom
Aliexpress UK