Airtightness is not something that has been achieved by historic construction. Everything, from gaps in floorboards through to the presence of chimneys and poor window installation can contribute to a lack of air sealing. As construction and design are increasingly judged against standards of both safety and energy efficiency, the need for buildings that excel at airtightness has become much greater. When you’re considering the overall efficiency and safety of your building, air sealing is as much of an importance as firestopping.
What is air sealing?
Air sealing is essentially the prevention of air leakage. A building that has achieved positive air sealing has a level of resistance to inward or outward air leakage. Air can either leak in or out through the various cracks and gaps in the fabric of a building and the design and construction of that building will have a big impact on how airtight it is. Factors such as wind against the outside of the structure, air buoyancy and condensation can be both the cause and effect of a lack of air tightness. Some of the most common air leakage paths in a building include:
- Window sills
- Gaps between floorboards
- Windows and doors that don’t close properly
- Gaps between dry lining and ceilings
- Recessed ceiling lights
- Gaps around service pipes
- Gaps between walls and solid ground floors
- Gaps around service pipes
Clearly, in any building, a balance needs to be struck between the requirement for ventilation and airtightness. But why is air sealing so important?
The importance of air sealing in firestopping
The airtightness of a building will have a role to play in how effective firestopping methods will be in the event of a fire, for example the use of gaseous fire extinguishing systems. This is particularly used for computer rooms or plant rooms, where fast extinguishing is essential to reducing downtime and stopping fire spread. For gaseous fire extinguishing to work most effectively, a room must be well sealed, otherwise the gaseous agent can escape and the fire could re-ignite or not fully extinguish.
Enclosure integrity testing to measure air sealing
Due to the fact that the sealing of a room can have such a huge effect on how well gaseous fire extinguishing methods work, the British and International Standard (BS:ISO14520) necessitates the need for an enclosure integrity test (or pressure test) to be carried out during system installation and re-tested annually. A formal report is issued, making any recommendations for adjustments to the room according to the results.
When you’re reviewing the fire performance of a building, air sealing has an important role to play alongside firestopping. If you’d like to find out more about how your business could benefit from air sealing, or to book your enclosure integrity test today, please get in touch with Hillmoore Fire Protection Ltd today on +44(0)1628 890122.