Smoke Seals

Intumescent strips and smoke seals can be used together or separately. Combined seals are used where both fire and smoke containment are required. Fire-only intumescent strips are used where smoke containment is not needed, and a smoke seal can be used on its own for draught and noise exclusion.

Types of smoke seals

• Brush seals — flexible bristle strips ideal for uneven gaps and sliding doors.
• Fin seals — rubber or silicone blades that flex against the door face for a tight seal.
• Acoustic smoke seals — designed to reduce sound transmission as well as block smoke.
• Rebated smoke seals — fitted into a routed groove in the door or frame edge, giving a concealed finish.
• Surface-mounted smoke seals — applied directly to the door edge or frame face without routing, making them ideal for retrofit projects.

How to install smoke seals

Smoke seals are typically fitted to the door edge, frame rebate or threshold, depending on the product type. Most door assemblies are designed around a 3–4mm perimeter gap between door and frame, and the seal is selected to suit this tolerance. Rebated seals sit flush inside a machined groove — usually installed at manufacture or by a joiner — while surface-mounted seals can be fitted on site with pins or adhesive backing, making them well suited to refurbishment work. Correct installation is essential to maintain the certified performance of the door assembly.

Compliance and standards

Smoke seals help buildings meet the requirements of Approved Document B of the Building Regulations, which governs fire safety in England and Wales, including provisions for smoke control at door openings. Performance is typically verified to BS EN 1634-3, the smoke and leakage test standard for door assemblies, which measures resistance to ambient and medium-temperature smoke. Specifying seals tested to this standard ensures door assemblies perform as intended in a fire scenario.

How we can help

At FireSealsDirect, we have a range of high-quality smoke seals available in several sizes and colours from Lorient and Pyroplex. Our team has extensive experience in fire stopping and smoke control specification across the construction industry, and we work closely with contractors, specifiers and facilities managers to select the right products for new build and refurbishment projects.

Take a look at our blog to find out how to soundproof a door or learn more about what a smoke seal is. Visit our Advice Centre for the latest updates on regulations, specifications and fire-stopping news, or call our Technical Helpline for free, impartial advice on selecting seals for your project.