- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 07 Jan 2019
An airbrick is a special type of brick that contains holes to allow the circulation of 'fresh' outside air beneath suspended floors and within cavity walls to prevent moisture building up as a result of cold or damp air ‘sitting’ in voids or empty spaces.
Airbricks have traditionally been manufactured using clay or cast iron. Some modern airbricks are made from plastic which can be more durable and enable a greater rate of airflow. An alternative to airbricks is the use of cast iron grilles, known as air vents.
Airbricks should be located and installed so as to maximise the cross ventilation in the underfloor voids, and should be kept clear of obstructions. A consideration when installing a conservatory is that airbricks on the wall of the house can be blocked by the conservatory structure or by vegetation, earth, and so on. Similar care must be taken when constructing extensions, to ensure that ventilation air paths are not obstructed, or that alternative air paths are provided.
Airbricks can be positioned either above or below the damp proof course (DPC) level, and should ideally be incorporated on all sides of a building, typically at least 75 mm above the ground to prevent water ingress.
A disadvantage of using airbricks is that the small holes can allow pests such as mice, slugs, and wasps to enter a building. A possible solution is to fix wire mesh over the airbricks, or use specially-made airbrick covers, which can prevent entry of pests.
NB Weep holes are openings placed in mortar joints of facing materials at the level of flashing, to permit the escape of moisture, or openings in retaining walls to permit water to escape. For more information see weep holes.
 Find out more
 Related articles on Designing Buildings Wiki
Featured articles and news
Indoor environments should provide a multi-sensory experience.
We have a great range of introductory articles written by ECA.
7 of the most common myths, busted.
Consider a career in the electrotechnical industry.
Exploring local assets of community significance. Book review.
Wood-burning stoves should not be used in thatch-roofed buildings.
Servitisation, smart systems and connectivity.
What happens to the Construction Products Regulation if there is no Brexit deal.
The first step to long-term prosperity.
The status and rights of employees in construction
Continuing to share environmental best practice.