Trickle Ventilation Changes

Passive, Background Ventilation for Homeowners in England changed 14th June 2022 and in Wales on 22nd November 2022 and you must ensure any new windows and doors installed in your home after this date complies

New Building Regulations changed for Windows and Doors

  • June 15th 2022 was the introduction date for these updates in England, and November 22nd 2022 in Wales
  • The regulations do not provide a grace period for orders placed prior to these dates

What does this mean for homeowners?

Background Ventilation

Covered under Part F - Ventilation

This basically means that new windows in both existing and new homes will require the inclusion of trickle (passive) ventilation, and the amount of ventilation required will depend on the room status

Basically, all rooms with walls require background ventilation

Multi-Storey Homes Single-Storey Homes
Habitable Rooms 8,000mm2 10,000mm2
Kitchen (not open plan) 8,000mm2 10,000mm2
Kitchen (open plan) 24,000mm2 30,000mm2
Utility Room Not required Not required
Bathroom 4,000mm2 4,000mm2
Ensuite / Enclosed Add +4,000mm2 to another room Add +4,000mm2 to another room
Sanitary Room Not required Not required

Exception, if the total number of ventilators installed in a home's habitable rooms and kitchen are fewer than 5, then 5 must be the minimum except in single bedroom properties where there is a minimum of 4 background ventilators within the property

What if we have continuous Mechanical Extract Ventilation installed already?

If you already have a Mechanical Extract Ventilation system installed then a reduction or removal in the need or performance of the background ventilators may be permitted

Continuous Mechanical Continuous Mechanical with Heat Exchange
Wet Rooms Not required Should not be installed
Habitable Rooms 4,000mm2 Should not be installed

However, the Mechanical or Mechanical with Heat Exchange system needs to comply with the minimum air exchange requirements indicated within the official document linked to - and professional advice may be required to confirm this


Covered under Part L - Air-tightness

Windows and doors must connect to the main (primary) air barrier and the windows and/or doors taped to the surrounding structural openings using an Air Sealing Tape, with the option of using supplemental taping by use of gun sealants or compressible seals if required

Your window and door installer should incorporate this method of fixing and sealing into the project as standard,

The requirements for Windows and Doors will be

U-Value BFRC Energy Rating
Windows 1.4u Band B or above
Doors with 60% or more glazing 1.4u Band C or above
Doors with less than 60% glazing 1.4u Band B or above

Of course, when you order your installed Windows and Doors through Heronhurst, and installation is by us and within a domestic home and within the dates of these new regulations, we will ensure every requirement is met, and certification to back this up, for your peace of mind

Note that these regulations are in addition to the Purge (full room air exchange) ventilation and Fire Safety regulations that must also be met in almost every home

The full document can be access here