Passive Purple offer guaranteed passive house airtightness

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According to company managing director Alex White, the company’s decision to back its airtightness claims for the Passive Purple liquid vapour control membrane with guaranteed performance was a no-brainer: “If it’s installed by one of our installers or by Passive Purple we’ll guarantee 0.6 air changes per hour.”

White explains that the BBA certified product – which is VOC free and water based – also has remarkable radon resistance qualities and is certified as a radon barrier when used in ground floor build-ups and at ground floor to wall junctions. Radon, an invisible, odourless radioactive gas is the 2nd largest cause of lung cancer in the UK. Radon exposure in the home is associated with circa 1,100 deaths per year in the UK according to the NHS.

According to White, Passive Purple is class-C fire rated where most paper membranes have class-E.

White said Passive Purple’s robustness and flexibility is leading to it being used by a number of different offsite build system manufacturers including timber frame and SIPS manufacturers, in addition to the wide range of onsite applications, which can bring any build method up to passive house airtightness levels – from traditional masonry through to modern methods of construction.

“Passive Purple can be used in certain difficult locations as well as full envelopment covering,” said White. “It all depends on the score you’re trying to achieve.”

Also available as a brush or roller-applied product, Passive Purple arguably comes into its own when sprayed. “Using an airless spray machine, we can come and install 300 plus sqm of membrane a day with a single operative,” said White.

“We also know that purple isn’t every one’s cup of tea and as our product can be left on show in places such as car parks and commercial stair wells, we have got Airtight White, with all the same great features as the Passive Purple.”

Passive Purple is part of family run business Whites Carpentry Group which includes White Haus Bespoke Timber Frame, White Air, White Haus Bespoke Windows, Passive Schools and Intelligent Membranes Ltd.