Our large-capacity trickle vents deliver a tested equivalent area of approximately 4320 mm², providing high levels of background airflow for retrofit and replacement window installations. These vents are designed to support compliance with Approved Document F and other current ventilation standards, offering reliable performance where greater air exchange is required.

Ideal for energy-efficient refurbishments, these vents help manage indoor humidity and maintain healthy air quality without compromising the integrity or appearance of existing frames. Available in multiple colours to match uPVC, timber, and aluminium profiles.

Note: Equivalent Area (EA) performance is based on laboratory testing under standard routing conditions. It is the installer’s or designer’s responsibility to determine whether the total background ventilation provision meets the specific regulatory requirements for each project.