At Rensair, we live and breathe clean air

“Just as people expect pure water from the tap, or hygienic food from the supermarket, so too they expect clean air in buildings and shared spaces. It’s not just an expectation, it’s a human right.”

— Christian Hendriksen Co-founder & CEO

Clean air, for generations

For over two decades, we’ve been transforming commercial air filtration and leading the drive for better indoor air quality.

Our technology was developed by Henrik Hendriksen, a Danish ventilation engineer who created the world’s most lab-certified solution for reducing airborne pathogens, pollen and pollution in non-residential buildings.

Today, we’ve reimagined Henrik’s technology for the connected world and created Rensair – the world’s first air quality ecosystem, and a step-change in how we make indoor spaces healthier for everyone.

From clean air to carbon-cutting

We were proud to play our part during the
Covid-19 pandemic by helping healthcare
environments improve their indoor air quality and
create Covid-secure environments. The NHS
quickly became our largest customer.  

And along this journey we saw that our air quality
ecosystem could also be used to decarbonise
indoor spaces and help organisations lower their
energy use and emissions.

40% of a building’s energy consumption comes
from mechanical HVAC ventilation systems. By
optimising these systems based on real-time
occupancy and environmental data, we’re able to
help our clients significantly reduce energy
consumption – saving them money, reducing
emissions and helping them meet their
sustainability and Net Zero goals.

A better way to decarbonise

This discovery has inspired us to build the next generation of ventilation solutions for any indoor environment that uses mechanical ventilation.

We call it HVAC: Hacked.

Because by hacking antiquated HVAC technology and ventilation systems with our powerful air quality ecosystem, we make clean air and carbon-cutting go hand-in-hand.

Crucially, we avoid the need to ‘rip and replace’ existing ventilation systems, which is costly, disruptive and carries its own hefty carbon cost.

It’s a more sustainable and cost-effective approach to ventilation that will deliver a step-change in how buildings and indoor spaces are ventilated for decades to come.

Hacking HVAC systems all over the world:

Our mission is to provide clean air and lower energy consumption for every indoor space: from offices and co-working spaces to hospitals and dental practices, schools and lecture halls to hospitality venues, hotels, restaurants and retail outlets.

We’re the most certified air quality proposition in the industry, with two decades of leadership in commercial air filtration. Our award-winning air quality ecosystem is trusted by businesses, education, transportation and healthcare providers in more than 40 countries over five continents.

With operations in the UK, Europe, the USA and Asia, we’re bringing our next generation ventilation technology to the world and enabling both public and private organisations to cut carbon, costs and pollutants from their indoor environments.


Where we operate



We help organisations radically reduce energy consumption and save money across their real estate without ripping and replacing existing ventilation.



We improve indoor air quality in every classroom and lecture hall while bringing down energy costs – even in older buildings.




Our technology helps leading healthcare providers transform indoor air quality and improve patient safety by reducing airborne transmitted diseases.



Transport providers rely on Rensair to clean the air and make every journey healthier and happier for passengers and staff.

Let’s talk

Time to Hack your HVAC system, contact our team to save money, 
cut carbon and improve your IAQ.