Greenhouse Autovents from Bayliss Autovents

Bayliss Autovents are widely thought to be the best automatic vent openers on the market and are suitable for both wooden and aluminum windows and frames. Adequate ventilation is one of the most important aspects of greenhouse growing and our selection of autovents takes the guesswork out of this all important operation and ensures accurate, continuous venting 24 hours a day.

Bayliss Autovents have been produced since 1964 by our family business in Ashbourne, the gateway to the Peak District in Derbyshire. We are proud of the reputation we have for design, quality, reliability and service. We offer a range of autovents that covers almost any automatic ventilation requirement you may have.

Corrosion resistant construction	Balanced lifting action
Illustrated fitting instructions	Alternative finishes and colours
Customisable designs	Manufacturer's Guarantee

What does a Bayliss Autovent do?

It opens and closes a hinged vent automatically using energy from the warmth of the sun or the surrounding air. The hotter it gets, the wider it opens the vent.

"No longer do I have to decide whether to leave the ventilators open a little on warm summer nights or if it’s safe to open them on cold autumn mornings before I go to work. It’s all taken care of automatically and with perfect efficiency by a set of Bayliss Autovents."

Read how Bayliss Autovents made one gardener's life easier >

Guaranteed for 2 years

All our products are guaranteed for two years against faulty manufacture. Provided the unit has not been tampered with (i.e. the piston pulled out of the tube), damaged by the window being tied shut, damaged by unusually strong high winds or fitted incorrectly, then we will repair it free of charge if it is returned to us.

Our Autovents are not ‘throw away’ items and are designed and tested to last many years. However, each and every part of a Bayliss Autovent can be serviced should the need arise, and we carry spares for all our current units as well as many earlier models.

View the full range of autovents and spares in our Product Catalogue >

How does it work?

A strong metal tube contains a mineral wax which expands with heat. This pushes a piston which opens the vent via a balanced linkage. As the temperature drops, the wax shrinks and a strong stainless steel spring closes the vent and resets the piston. Learn more about the science behind Bayliss Autovents >

Why is the Bayliss Autovent better?

It has been designed by engineers who have been making automatic vent controls for over 40 years, and incorporates all the knowledge and experience gained during this time. All Bayliss Autovents have a strong stainless steel spring to give a firm closing force, and this virtually eliminates any risk from wind damage. The unit gives a balanced lifting action in the middle of the vent and this avoids any sideways thrust on the vent which can twist it or even push it out of position.

View the full range Bayliss Autovents in our Product Catalogue >

Custom designed Autovents

The details given on this site show our standard range of automatic ventilation units. However, because we design, make the components and assemble them 'in house', we are able to offer special versions of the Bayliss Autovent. Variations can include alternative finishes and colours, different operating temperature ranges and even special designs for specific applications. Contact us to discuss your requirements >