More On Mould Prevention - One Solution trickle vents on windows and patio doors

Mould on patio door and frame.

Mist on window.

I asked AI the cost of installing trickle vents. Copilot told me

What is the difference in cost between a patio window without trickle vents and one with trickle vents?

The short version:

Adding trickle vents to a patio door usually increases the cost by about £5–£20 per vent, depending on the type and supplier. That means the overall price difference between a patio door with and without trickle vents is typically £10–£40 for a standard two‑vent setup.

💷 What drives the cost difference

The price gap comes from the vents themselves, not the door. Based on current UK retail pricing:

• Basic uPVC trickle vents cost £5–£7 each.

• Mid‑range adjustable vents run £6–£15 each.

• Acoustic or premium vents can be £10–£20+ each.

Most patio doors need one or two vents, depending on width and building‑reg requirements.

🧩 What installers typically charge

Installers often:

• Include the vent cost plus a small labour charge

• Add £10–£30 to the door price

• Or simply bundle vents into the quote for new-build‑compliant installations (since vents are now required in many cases)

So the real‑world difference you’d see on a quote is usually £20–£50, unless you choose acoustic vents, which can push it higher.

🪟 Should you include them?

A few practical considerations:

• Required in many new installations under UK ventilation rules.

• Help reduce condensation, especially on patio doors.

• Some people dislike the look or occasional wind noise, but they do improve air quality.

AI says - If you want, I can help you estimate the cost for your specific door size or compare vent types so you know whether the upgrade is worth it for your home.

The short answer

You can add trickle vents to most existing uPVC, aluminium, and timber patio doors, but it requires cutting into the frame, so it’s usually a job for a window installer rather than DIY.

🔧 What determines whether it’s possible

1. uPVC patio doors

• Usually possible.

• The installer cuts a slot in the head of the frame and fits the vent internally and externally.

• The main limitation is whether the steel reinforcement inside the frame is in the way.

2. Aluminium patio doors

• Often possible but more specialist.

• Aluminium frames are harder to cut and may have thermal breaks that need careful handling.

3. Timber patio doors

• Easiest to modify.

Can I fix vents to an exiting patio door?

 AI told me - see start above.

Useful Websites

https://www.nea.org.uk/get-help/resources/dealing-with-damp-and-condensation-national-energy-action-leaflet/