Building Regulations – Document F

The time for change has arrived and it is called Building Regulations – Document F. Until now, regulations suggest that if the existing item doesn’t have trickle vents, they will not be required in your replacement items. However, if the existing item does have trickle vents, or is going into a new aperture, the item being installed must include trickle vents. New legislation from Building Regulations has now been enforced for all glazing installations taking place from 15.06.2022.

Aluminium Bi-Folding doors including trickle vent

What is Document F?

Document F has been introduced to maintain or improve indoor air quality. The areas specific to the glazing industry indicate the need for trickle vents. They are now required in doors and windows in almost all circumstances. Document F is relevant to many trades, so be sure to check that any work you have done around your home complies.

What does this mean for me?

My Windows / Doors already include trickle vents

There is no notable difference to the new regulations. This means your replacement products must include trickle vents. The replacement trickle vents cannot be smaller than the ones currently in the window or door being replaced.

My Windows / Doors are going into a new aperture

There is no change from the existing regulations. All items being installed into a new aperture must include trickle ventilation.

My current Windows / Doors don’t include trickle vents

When replacing windows or doors in a habitable room, the replacement product must include them. The size of the trickle vent depends on the purpose of the room, but if the minimum ventilation cannot be achieved, the closest possible equivalent must be used.

Are there any exceptions?

There are a few exceptions, but these do not apply to most replacement items. If it is unfeasible for the new window or door to contain a trickle vent then one cannot be installed. Also, if your home has mechanical ventilation with a heat recovery system, then trickle vents are not required.

If the property has “continuous mechanical extract ventilation” no trickle vents are required in wet rooms (kitchen, utility, bathroom, WC), but you must fit 4000mm² equivalent area in all other rooms. Other exclusions include properties that are listed or in a conservation area.

As a FENSA approved installer, we will ensure that you are aware of whether trickle vents will be required and install your products in line with all regulations.

FENSA Trickle Vents Installation Requirements Guide

Approved Document L – Energy Efficiency

Another change that has come into force affects the minimum acceptable thermal performance requirements for new windows and doors. These changes mean that:

  • The new products must be no less efficient than what is currently installed
  • Either achieve a whole window or door value of *1.4W/m²K or:
  • (Windows) have a Window Energy Rating of B or better
  • (Doors with a glazed area greater than 60%) have a Door Set Energy Rating of C or better
  • (All other doors) have a Door Set Energy Rating of B or better

Why is it important to comply with the new Building Regulations?

Regulations have been put in place for a reason, to improve the quality of products, and installations. We ensure that as a company, we follow all regulations. If your installation does not comply with regulations it can cause numerous issues for you. If your installation is non compliant and you were to receive a building inspection, you could be told that your products need to be replaced. This could cause a significant loss of money for you and also cause issues if you were to try and sell your house. We have built a very high reputation which we endeavour to uphold. Our customers mean everything to us and by ensuring that all regulations are met, everyone can be safe in the knowledge that we can be here to service all of our past and future customers’ needs.

If any company suggests that they can get around the regulations, this should be a cause of great concern. No company is above regulations. If they aren’t met, you run the risk of causing problems that could cost you dearly.

I want to find out more

At MPS, we take care of the hard work for you. It is our job to ensure that all of the relevant standards and regulations are met, taking the worry and hard work away from you. From your initial contact with our consultants, all the way through to installation from our in house teams of installers, we ensure that you receive nothing less than the best. Our experts take into account your requirements, desires and budget to provide you with a quotation that meets your needs.

We are happy to provide a quotation online through our contact form but if you would prefer, we can arrange a visit to your property at a date and time suitable for you. We’re aware that budget is often a deciding factor and we are on-hand to talk you through the available options and offer our expert advice as market leaders for 30 years.



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