Air bricks are necessary to achieve the required levels of ventilation as stipulated in Building Regulations Approved Document J 2010.

Air bricks - also known as vent bricks or ventilation bricks - are traditionally made of clay, and most still are today. Air bricks can be installed quickly and easily.
Rooms with a cavity wall, a void under a wooden floor, or that contain a gas appliance, need air bricks and cavity wall ducts to increase airflow and minimise the possibility of damp or accumulation of gases.
Air bricks are particularly important for properties with timber flooring that has a void underneath.

Without ventilation, the air in the void may become stale and humid.

This can lead to mould and potentially dangerous gases collecting within the underfloor void.

The installation of air bricks allows air to flow under the floorboards, helping to regulate temperature and minimise the formation of condensation and mould.