If you’re looking into getting fire doors, you might have heard about intumescent strips. These strips are important parts of a fire door. When they get hot, the strips expand quickly to fill gaps and block smoke and fire.
But the big question is – do these strips go on the inside of the moving door or on the frame? Where exactly you put them matters. Knowing what’s normal helps make sense of the best choice.
By default, intumescent strips usually go inside the door frame. They line the sides and the top of the frame. Putting them here lets them react fast even with just some heat, but locks, wires, and bolts on a door make it hard to place strips well.
Therefore, for most regular doors, the normal way is putting strips on the frame, but some custom doors are made to have the strips on the door edge instead.
The specific features and intended use of a fire door can impact the best spot to place intumescent strips. Factors that influence mounting location:
Doors with built-in electronic card/fingerprint access control locks may benefit from mounting strips along the door edge instead of the frame to simplify wire routing.
The number and position of key deadbolts/lock points on the door can determine ideal space to fit continuous intumescent strips without interfering when engaging with receivers on the frame side.
Intumescent strips lining door edges with large vision glass cutouts help make up for insulation gaps increased by perimeter glazing spacers stopping flush fire-rated window panes.
Heavy traffic doors endure more potential seals damage along vulnerable leading door edges For longevity, commercial fire doors often opt for extra protected intumescent sealing integrated into frames.
For frame or door mounting, the heat exposure will hit the strips differently. Depending on which side faces out, the strips react faster or slower. Testing relies on the strips getting heat on their “front”—if flipped around during fitting, the reaction gets weaker.
External frame strips are common for heavy-use doors, but outside strips activate a little slower to heat.
No matter which type, strips are useless unless sized and installed precisely. Gaps or incomplete joints prevent the big volume swelling that blocks smoke and fire when hot.
Proper room for expansion also matters—too rigid and the barrier effect fails. That’s why certified door tests use the right strips mounted correctly to guarantee effectiveness.
Without experience, recreating ideal conditions is hard. That’s why involving specialists like Bradbury Group gives reliability – our tailor-made steel doors seamlessly integrate fully-tested strips on the frame or leaf edge.
In the end there’s no absolute rule – custom applications and door functions require case-by-case decisions on strip mounting conventions by accredited manufacturers. For guaranteed regulatory compliance and performance, let us handle integrating expert solutions.
Rely on Bradbury Group for compliant fire rated doors suited to any building type. Contact our team today to explore your best choices!
