Intumescent Vents

Intumescent materials typically last for the life of the door, if they are not damaged or exposed to conditions that could degrade them, for instance vandalism and tampering, extreme moisture or physical wear. It's important to inspect the pads periodically during regular fire door maintenance.

Enhanced fire safety: When ventilation is required they help to contain fires, preventing them from spreading rapidly

Smoke and gas protection: Intumescent vents can, after being exposed to heat, prevent smoke and harmful gases from leaking through gaps 

Cost-effective: They are an affordable fire safety measure compared to buying pre made / hung door sets and frames

Legislation: When ventilation is required in a fire door, fitting intumescent vents is a legal requirement. Fire door hinge fire test evidence is gained when intumescent hinge pads are fitted

Easy installation: They can be retrofitted into existing doors and frames

An intumescent vent is a fire-rated vent manufactured from heat-sensitive intumescent material. The intumescent material will expand when exposed to heat to seal fire doors and prevent the spread of fire. 

• Fire-rated doors: To provide ventilation while maintaining the fire-resistance rating
• Ductwork and shafts: To allow air circulation without compromising fire safety
• Fire compartments: In buildings where smoke and heat need to be controlled to prevent the spread of fire

The intumescent vent is a fire-rated vent manufactured from heat-sensitive intumescent material. Normally, the vent remains open to allow air flow. When exposed to high temperatures, the intumescent material expands, sealing the vent and preventing smoke and flames from passing through. 

• Cut the aperture in the door
• Line the aperture with a 6mm hardwood liner
• Apply a bead of our intumescent acrylic sealant centrally and spread the sealant across the full width of timber liner, to achieve a thickness of 0.50mm
• Install the grille into the aperture
• Secure the system into place using steel pins (not supplied). Alternatively, secure the system using self-tapping screws
• Fit cover plates on both faces of the door

Free air flow requirements is normally what is specified by the architect, alternatively it's as simple as knowing the size of the hole in the door.  

We state online and, in our catalogue, both free air flow and overall size. 

Importantly the vents are sold separately to the grille cover so don’t forget to order either 1 or 2 grille covers for 1 or both sides of the door. 

Intumescent vents are designed to manage the balance of fire safety with the need for ventilation. Without these vents, fire-resistant barriers could become ineffective due to the lack of airflow, leading to heat buildup, smoke accumulation, or even system failure. Intumescent vents ensure that fire protection is maintained without compromising the building’s ventilation needs.

On 14th June 2017, the Grenfell Tower fire spread primarily through its external cladding, tragically killing 72 people. The Grenfell Tower Public Inquiry identified matters of concern relating to construction products including the testing and certification of materials, design and choice of materials, fire doors and smoke extraction systems.  

The resulting information has changed the landscape of responsibility, holding individuals responsible for their actions. 

Like all fire safety devices, intumescent vents should be inspected regularly to ensure they function properly. Maintenance includes: 

• Ensuring the vent is not blocked or obstructed
• Checking the intumescent material for signs of damage
• Testing that the vent closes properly under heat conditions
• Replacing or repairing the vent as needed

The main difference is that intumescent vents are designed to react to heat and close automatically during a fire, whereas regular vents do not provide any fire protection. In contrast, traditional vents could allow fire and smoke to pass through freely, compromising safety in the event of a fire.

Intumescent vents are suitable for most commercial and residential buildings, especially those with fire safety requirements. However, the specific installation requirements and product certifications may vary depending on the type of structure, the level of fire protection needed, and local fire offer requirements. Check if you are unsure.

Our Responsibility: Offer and guide customers through fire door ironmongery legislation and offer tested and accredited fit for purpose products

Your Responsibility: To fit appropriate tested and accredited ironmongery when fire doors are required

Joint Responsibility:  Communicate effectively to ensure correct specification, selection, fitting and maintenance of ironmongery fitted to fire doors. If you're not sure, please ask us

“More importantly still, I think you need to examine why you are doing this. You should be doing this because it’s the right thing to do. Not because legislation make you do it.” 

Dame Judith Hackett

Yes, as you would expect, our intumescent vents are fire-rated and come in various sizes for free air flow requirements.  

Our air transfer grille system (vent and grille covers) are tested to BS476 part 20/part 22:1987. - 30 and 60 minute rated. 

Intumescent vents should be stored in a cool, dry place and protected from damage. They do not require special handling, but care should be taken to avoid exposing them to extreme conditions like heat and moisture prior to installation.

The vents themselves don’t require active maintenance, but they should be checked periodically to ensure they are not compromised. If the door or hinges are removed or replaced, the hinge pads should also be inspected and replaced if needed.

Yes, intumescent vents are almost always used in combination with other fire-sealing materials like intumescent strips, fire-rated glazing, or door sweeps to enhance the overall fire protection of a door assembly.