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What Are Trickle Vents and Why Are They Needed?

(4 min read)

Quick FAQs

Is it a requirement to have trickle vents?

Yes. As of June 2022 most buildings, with exceptions such as listed buildings, must have trickle vents when new windows are installed

Are trickle vents available in different colours?

Yes, there are different types and colours of trickle vents to match your windows, doors and property

Do You Need to Improve the Quality of the Air in Your Room?

You are probably required to install your windows and doors with trickle ventilators because of the new building regulations, starting from 15th June this year.

If you’re not an expert in the window industry but want to allow fresh air to enter a room, filter the polluted air out, and meet the legal requirements simultaneously, don’t worry; scroll down and check out all the information we’ve prepared for you!

Definition of Trickle Ventilation

Trickle ventilation can be provided to ensure there is always an adequate level of background ventilation. Trickle ventilators are typically manually maintained slots integrated into window frames. They are commonly operated by opening or closing a flap depending on the need for ventilation. However, they are intended to be left in the open place.

Also, they might be self-balancing, with the size of the open position changing automatically; depending on the air pressure difference across it, they may decrease the risk of draughts during windy weather.

Criteria for the Size of a Trickle Ventilator

The criteria for the size of the trickle vent are not dependent on the size of the room; it is dependent on the kind of room. Here are the typical room types of a home and their equivalent area (EA):

  • Habitable room (bedrooms, living room etc.) – minimum 8000mm EA
  • Kitchen – minimum 8000mm EA
  • Bathroom/WC – 4000mm EA
  • Conservatories – 1000mm EA

In addition, it is essential to mention that all trickle vents must have the size marked on the vent.

Properties That Do Not Need Trickle Vents or Need Permission First

As an exception, for all the building types below, we would need to contact the local authority to check if they are happy to have trickle vents installed:

  • Listed buildings
  • Historic buildings
  • Conservation areas

Modern buildings tend to be virtually sealed from the outside. Modern, naturally ventilated buildings might suffer issues, such as condensation, when windows or other ventilators are closed, for example, in the winter or at night. It is highly recommended that trickle ventilators are located approximately 1.7m above the floor level to avoid producing cold draughts.

Houses near railways, main roads and airports are not exempt just because they are noisy; you would need to install attenuator (acoustic) vents. However, these are extensively bigger and more pricey.

Why Do We Need Trickle Ventilators?

As a result of better-sealed windows and higher insulated houses, houses aren’t naturally ventilated as well as they were in years gone by. This makes an issue for the inhabitants, as many pollutants build up inside the home, which, if not removed, may cause harm.

Condensation can form in badly ventilated rooms too, which may lead to a build-up of mould. This is where trickle ventilators come in. Increasing the airflow in a home reduces the build-up of condensation and harmful pollutants, leading to a cleaner home environment.

Advantages of Installing Trickle Vents

Apart from the necessity to have trickle vents to comply with building regulations, there a surprisingly a few other reasons to consider:

  • Maintain a comfortable temperature 24/7 without having to worry about making the room too hot or cold
  • Conserve energy with minuscule trickle vents for a constant, moderate temperature
  • Allow fresh air to flow into the room to meet regulations
  • Deplete the energy efficiency goals for which they were installed
  • Prevent cracking
  • Improve energy efficiency(low heating bills)

Are There Different Types of Trickle Vents With Varying Impacts?

Trickle ventilators may fit all new window frame materials, such as PVC-u, timber, steel and aluminium and are available in many colours to match your window frames.

Through window frame design

A through-frame trickle vent design is usually placed through the top of the window frame. The trickle vent is incorporated into the window frame itself.

Over-window frame design

An over-the-frame design is utilized when it is impossible to fit the trickle vent via the window frame. It allows the ventilation to be routed over the framing or head of the windows.

Glazed into the window

The trickle ventilator fits into the glazed window position along the top of the sealed double-glazed glass window unit.

Acoustic trickle vents offer noise cancellation and better energy ratings but are hard to get hold of and cost the earth.

Conclusion – Are Trickle Vents Required?

As discussed above, trickle vents are usually needed with new installations – if you are in doubt, contact us and we’ll let you know if your property is exempt.

Regulations aside, trickle vents allow cool air to continue flowing through your home while your windows are locked and they may reduce/remove the risk of condensation. They may also remove stale air from turning around your home, which prevents the build-up of unwanted odours.

So don’t wait; let the fresh air circulate in your room and get a fully compliant installation with the highest standards. Call or email the glazing team and they’ll help you take the first steps.

Need advice on trickle vents?

Talk to one of our glazing experts to find out more trickle vents.

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David Bryant
David Bryant
Very happy with our new door . The support team kept us up to date on everything and the guys on the installation team were early , friendly and professional. Great value all round
Kate Hulbert
Kate Hulbert
Was looking for a new front door, to replace our tragically 80's monstrosity. The Three Counties website was great as i could see and design the door i wanted and then get a quote for it. The sales team was really quick to respond, and not at all pushy. A survey was easily arranged, to confirm sizes etc and the installer turned up precisely on time, was super friendly, efficient, neat and very tidy. Whole process took about 4 weeks, beginning to end, and I now have the door of my dreams! The only downside is my neighbors keep pestering me for details of who did the job. No hesitation in recommending Three Counties.
Nikki Wade
Nikki Wade
I'm very happy with my new conservatory - Mark and David did a brilliant job of the build and resolved any issues I had to make sure everything was finished to a really high standard.
Dominic Blood
Dominic Blood
This is the second time I have used Three Counties , a few years later and in a different house this time. It’s great to see the quality of the windows and workmanship have remained 5*. A stress free installation from start to finish, all windows installed have transformed how our 70s style house looks and now no worries of mould as a result of the old timber framed windows. The Installers who completed our job were amazing, and I mean amazing! Hard working, extremely skilful at their trade, polite and very tidy. Each day when they left they hovered up and left the place in the best condition they could. The whole process from the initial quote , measurements and dealing with the office team before and after the installation has been a true pleasure , if only all businesses were as efficient as this. Highly recommended for anyone considering new windows or any other products they provide and I won’t hesitate to use them again. Thank you Three counties!
Kim Stevens
Kim Stevens
I shopped around and three counties came in at the most reasonably priced, and I used the buy now pay later option. Really happy with my new door and window, which were both fitted in one afternoon. The customer service was very good throughout and everything went smoothly.
I had some windows fitted a few years ago and have recently had a problem with one of the locking mechanism failing. I called 3 Counties, who had a base call out charge, where a lovely lady took my details, refered to my file and we agreed a date when the fitter would come out and inspect the issue. Paul arrived bang on time and was very helpful. He checked the window, confirmsd the issue and promptly fixed it there and then with a replacement part he had on board his van. He was polite and knowledgable. Very efficient. Thank you 3 Counties.
samie dowling
samie dowling
I had new windows fitted and they look amazing, make such a difference. House is much warmer and soundproof! Staff were very professional, done the job so quickly and cleaned up after. Would definitely recommend.
Ywain Martin
Ywain Martin
Excellent service throughout the process. Very happy
Victoria Stone
Victoria Stone
Very happy with our new windows. Fitters were respectful and tidy. From start to finish. Thanks again.