An open vent in a greenhouse

How to fit an automatic greenhouse vent opener

Find out how to fit an automatic greenhouse vent opener with the help of our practical step-by-step guide.

Do it:

Jun, Jul, Aug

Takes just:

two hours

Keeping your greenhouse cool in summer is essential, as high temperatures can cause heat stress, damaging your plants and potentially, your crops.

Damping down and providing shading in the form of blinds, screens and shading paint can help, and it's really important to encourage good air circulation by opening the doors and vents.

You can make sure your greenhouse ventilation is constantly regulated during hot summer months, whether you're at home or not, by installing an automatic vent opener. It contains a wax that expands when heated, opening the vent. When the temperature falls, the wax contracts and the vent closes.

UPVC greenhouses have lightweight roof vents and may require a stronger vent opener to keep them closed or prevent them being blown away - check before you buy.

Available at garden centres or online, automatic vent openers are quick and easy to install - here's how to do it. 

You will need

  • Greenhouse
  • Automatic ventilation kit
  • Screwdriver
  • Screws


Place the opener in the centre of a window vent and mark the position of the holes on the window frame and greenhouse frame.

Screw the automatic window opener to the frame of the window then check that the window can open and close.

If necessary, adjust the amount the window opens by rotating the main tube of the vent opener.

On a sunny day, watch and wait to see that the vent is opening properly.


Cold frame

Essential greenhouse kit

Find out about more useful items for your greenhouse in our guide to essential kit for your greenhouse

Discover more ideas and inspiration

Related content

How to grow gloriosa

How to grow herbs from seed discs

How to take cuttings from house plants