Airtight White: High-Performance Airtight & Vapour Control Membrane for Internal Applications - Spray-applied Airtight Liquid Membrane

Passive Purple Airtight White – Airtight Membrane. The world’s most airtight liquid vapour control membrane. BBA Certified and Passivhaus Certified Airtight Vapour Control Membrane.

A polymer-based liquid which is applied with an airless spray device or roll applied and dries to form a permanent flexible airtight seal and vapour control layer. With excellent adhesion to most forms of construction substrates. Certified Airtightness of 0.03 ach on any substrate it is adhered to.

Passive Purple Airtight White adheres to any form of construction, allowing you to achieve maximum results for your desired goal. Once dry, Airtight White forms an extremely tough yet flexible polymer, water control membrane allowing it to move with the building settlement while also being super effective against impact damage. Airtight White, airtight membrane eliminates the inevitable rips, tears, unstuck tapes, staple holes, and many repairs you would expect to find on the classic paper membranes.

We have eradicated the need for paper, tapes and staples through this product, which eliminates all the problems that came with it (labour time, large quantity of damage repairs and waste material).

Airtight White is an airtight coating that is spray applied with an airless spray device. It is designed to cover all areas of an external envelope (warm side of the insulation) of a building, including difficult connections in floors, walls, roofs and joist areas. As long as Airtight White is used on the warm side of the insulation, it can be applied to either face of the external envelope.

The surface material where you apply Airtight White needs to be dust-free, solid and closed before starting the application. A closed surface implies that holes and joints need to be closed beforehand. Large holes and joints (> 5mm) can be closed with fast setting cement-based products or polyurethane foam. Small holes and joints (2-5mm) can be closed with Airtight White Liquid Brush. This is a much thicker (paintbrush applied version of Airtight White).

After these preparations, Airtight White radon barrier membrane can be sprayed with an airless paint spray device. This fast application method allows a single operative to apply up to 300 m² per day.

The wall/ceiling connections also need to be made airtight, especially when the connections are made of two different types of construction materials such as red brick/concrete or steel/concrete. Different construction materials react differently to changes in humidity and temperature, moving at different rates, which can lead to small cracks in plaster or another type of finishing. That movement can create air leaks that cause your building’s energy performance to suffer and potentially open the gateway for damp and mould to appear.

Both products can be used for these wall/ceiling connections: Airtight White vapour control membrane can be applied with an airless paint spray device. Or Airtight White Brush can be applied by brush. If you don’t have an airless sprayer but would still wish to install Airtight White yourself, don’t worry, we have a roller version for you. It may take a bit longer, but it gets the job done.

Pipe and wire penetrations can be the downfall of any air tightness testing. Airtight White and Airtight White Brush are applied around objects that penetrate any surface to the external envelope, sealing where most tapes and membranes fail. 

Before you apply Airtight White or Airtight White Brush, first apply polyurethane foam around any penetrations. After hardening, remove the excess foam and apply a generous amount of Airtight White Brush with a flat paintbrush. In all cases, apply a sufficient, well-covering layer to guarantee airtightness and a strong radon barrier and vapour control membrane.

Airtight White can be applied (and is tested) on different construction materials such as concrete, brick, wood, PVC, aluminium and polyurethane foam. With a coat of Airtight White, the whole window/door reveal can be made airtight.

Working method: cut off the excess polyurethane foam, and apply Airtight White Brush.

Features and benefits:

• The product is ready to use.
• Volatile organic content (VOC), carcinogen-, ammonia- and formaldehyde-free.
• British Board of Agrément (BBA) and Passivhaus certified.
• Certified radon barrier.
• A Passivhaus certified score of 0.03 ACH which is 20x lower than the required 0.6 air changes per hour (ACH).
• Can guarantee a score of 0.6 ACH.
• A single installer can apply up to 300 m² of Passive Purple a day using an airless spray device. Construction is sped up, and labour costs are dramatically reduced with this easy airtight pain.

Technical characteristics:

• Density: 1.2 kg/L.
• Resistance to fatigue movement (to EOTA TR008): No cracking or delamination.

- Adhesion (to ISO 4624):

• Red brick: 1.5 N/mm² (dry), 1.4 N/mm² (moist).
• Concrete: 1.9 N/mm² (v) (dry), 1.6 N/mm² (v) (moist).
• Ytong block: Adhesion value exceeding substrate strength, 0.8 N/mm² (dry), 0.7 N/mm² (moist).
• Gypsum block (Isolava): 1.6 N/mm².
• Oriented strand board (OSB) wood: Adhesion value exceeding substrate strength, 0.6 N/mm².
• Multiplex wood: Adhesion value exceeding substrate strength, 0.6 N/mm².
• Ethylene propylene diene monomer (EPDM) rubber ISO 4624 (Tridex): Adhesion value exceeding substrate strength, 1.3 N/mm².
• Roofing: Adhesion value exceeding substrate strength, 0.7 N/mm².
• Plaster (Knauf MP75) on PASSIVE PURPLE: Adhesion value exceeding substrate strength, 0.4 N/mm².
• Thin plaster (ALLTEC) on PASSIVE PURPLE: 0.8 N/mm² (v).