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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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Paul Wallis
Paul Wallis
We recently decided to replace our front door, and could not be happier with the result! Thanks so much to Kate, for her time and understanding. Cannot say enough good things about the installation, and Cameron was tidy and efficient. It's been a pleasure to work with Three Counties recently, doors and windows. Many thanks!
Danielle Horsley
Danielle Horsley
Lovely looking door
Agatha W
Agatha W
Three Counties have been superb, their customer service is great and their workman were polite, cleaned up after themselves and the workmanship is excellent!! I am very pleased with their work and would happily recommend them.
Tom Winter
Tom Winter
Excellent service!! We had 21 windows and 3 doors installed and very happy with it all. The process from start to finish was stress free and Ron and Lee who installed the windows and doors were great. Would definitely recommend!
Phil Redhead
Phil Redhead
Just had my tatty old windows replaced by Three Counties, and it’s been a highly professional job from start to finish. Communication from the administration team was prompt and courteous at all times, and installation ended up being much quicker than advertised projections. Installation was without issue and the lads who did the work were amenable to my requirements and did an excellent job. Very happy with the entire process. Three Counties were recommended to me by friends and I can certainly now recommend them to others.
Mark Boyce
Mark Boyce
Bought two new windows and a new front door from Three Counties, was very impressed with the attitude of all staff, who were friendly and informative. Price was good, and installation completed without a hitch - very happy with the final product, and would definitely use again.
Paul Picknett
Paul Picknett
We have just had all our windows (18) replaced, french doors (20 and side panels (2) by Three Counties. We could not be more pleased with their workmanship and the finished product. They left the property incredibly clean after each day, and this despite the messy nature of ripping out old windows and frames. We were kept informed at each stage and a minor snagging issue was resolved promptly and efficiently after installation. A first class service. We would not hesitate to recommend Three Counties.
Anna Trevelyan
Anna Trevelyan
Three Counties have now installed several windows and doors on our house and they're always my go-to company. I used another before I discovered them and they let me down, but I absolutely cannot fault Three Counties. From the moment you contact them they're courteous and professional, and they keep in touch with timescales and installation times. Friendly installers too, who go above and beyond. You'd think all this great service would cost more but they beat other companies on price. Highly recommended and trusted, I'd never go anywhere else now.