GB2510614A

GB2510614A - Fire seal

Info

Publication number: GB2510614A
Application number: GB1302299.1A
Authority: GB
Inventors: Stephen Hutsby; Ray Anning
Original assignee: INTERIORS Manufacturing Ltd
Current assignee: INTERIORS Manufacturing Ltd
Priority date: 2013-02-08
Filing date: 2013-02-08
Publication date: 2014-08-13
Anticipated expiration: 2033-02-08
Also published as: GB201302299D0; GB2510614B

Abstract

A fire seal 30 for sealing a gap 29 between opposing faces 20a, 20b of first and second structural members 26, 20. The fire seal comprises a first end 52 and a second end 54, the first end being dimensioned so as to be wider than the second end, and a generally tapered profile extending between the first end and the second end. The fire seal is formed from a resiliently deformable material and a fire-retardant material. The resiliently deformable material and profile of the seal is such that, in use, the fire seal can be deformed into a gap between opposing faces of a first and second structural member and once in position is mechanically held. The seal may be formed by extrusion, and may be formed from a closed-cell foam comprising nitrile rubber and having a graphite intumescent material distributed throughout. An assembly comprising the fire seal, first and second structural members and an architrave 60 to be positioned over the first end of the seal may also be provided.

Description

A fire seal

FIELD OF INVENTION

The present invention relates to a fire seal, which is particularly, but not exclusively, intended for use in sealing a gap between first and second structural members. The invention also relates to an assembly comprising a fire seal, as well as first and second structural members.

In particular, the seal of the present invention is suitable for providing a fire seal between a door frame and a building wall having a door opening in which the frame is located.

BACKGROUND

In public buildings such as hospitals, airports, retail shops, factories, etc., door installations nccd to comply with fire regulations and arc inspected during installation by an inspector to ensure compliance.

When installing a door frame, there is a gap between the frame members (i.e. the two uprights and top) and the surrounding wall which defines the door opening. In the event of afire, this gap provides a passageway for smoke and noxious gases, so needs to be sealed in order to meet fife regulations.

In our earlier application GB2472402 we disclose a seal comprising an elongate strip with a T-shaped or L-shaped cross section that can be adhesively attached to the frame mcmbers to covcr the gap between the frame members and the surrounding wall. In many instances this has been found to work well, but requires additional installation steps associated with removal of a backing to the adhesive, and may not adhere satisfactorily if the members on either side of the gap are not co-planar. This type of seal also requires the gap width to be within a relatively small range, the seal being ineffective if the gap width lies outside this small range. A further embodiment of this application illustrates a rounded seal that is intended to be inserted wholly within the gap, and has intumescent material embedded within. Whilst this negates some drawbacks of the other embodiments, it is still only capable of fitting in a relatively limited range of gap sizes; if the gap size is too small, the seal won't be received in the gap or will protrude too far out of the gap, and if the gap is too large, the seal may not be held properly in place and may become lost' within the gap, so it is extremely difficult to remove.

The present invention seeks to overcome or mitigate the problems associated with the

prior art.

SUMMARY OF INVENTION

A first aspect of the present invention provides fire seal for sealing a gap between opposing faces of first and second structural members, the fire seal comprising: a first end and a second end, the first end being dimensioned so as to be wider than the second end, and a generally tapered profile extending between the first end and the second end, and wherein fire seal is formed from a resiliently deformable material and a fire-retardant material, such that, in use, fife seal can be deformed into a gap between opposing faces of a first and second structural member and once in position is mechanically held in place.

The shape of the profile ofthe seal enables it to be easily installed; the user simply has to push it into a gap and the tapered profile of the seal will engage opposing faces of structural members, holding it in place mechanically. No adhesive is needed and it is easy to insert even when the structural members either side of the gap are not co-planar, due to poor workmanship for example.

The generally tapered profile increases the range of gap widths that can accommodate the seal; if the gap is wide, the seal just needs to be pushed in further before the outer edges engage the opposing faces of the structural members, and if the gap is narrow, the seal will still fit due to a combination of the resiliently deformable material and the narrow second end.

If the gap is below a predetermined width, the seal will not need to be pushed in all the way; a section of the seal will still protrude out of the gap. This advantageously allows the seal to be easily removed. It also prevents the seal from being lost within the gap.

The seal may be generally wedge-shaped.

The profile of the seal may decrease in width at a non-constant rate from the first end to the second end.

The profile of the seal may have at least one planar face.

At least one side of the profile may comprise a first planar face and a second planar face. An angle between the first planar face and a longitudinal axis of the seal extending the length of the seal from the first end to the second end may be greater than an angle between the second planar face and the longitudinal axis. This profile shape advantageously has two surfaces at different angles, which enables the seal to be appropriate for an increased range of gap sizes. The angle between the first planar face and the longitudinal axis is large for contacting faces of structural members with a wide gap therebetween. The angle between the second planar face and the longitudinal axis is small for contacting faces of structural members with a narrow gap therebetween The seal may comprise a lip that extends from the tapered profile at the first end.

At least one side of the profile of the seal may comprise a curved surface, for example a concave or convex surface, or a profiled surface, for example the surface may include projections, the projections may be shaped to ease insertion of the seal into a gap but to resist movement of the seal out of a gap. The profile of the seal may include an undulating surface.

The profile of the seal may be symmetrical about a longitudinal axis of the seal (extending the length of the seal from the first end to the second end).

The seal may be integrally formed. For example, the seal may be formed by extrusion.

The seal may be elongate. The seal may have a a constant profile along its length. This enables the seal to be manufactured very simply, for example, the seal may be manufactured in a single extrusion process.

The resiliently deformable material may be a foam, preferably an elastomeric foam, and preferably a closed cell foam. Even more preferably, the foam comprises nitrile rubber.

The resiliently deformable material of the seal may be impregnated with fire-retardant material such that the fife retardant material is distributed therethrough. For example, the fire retardant material may be fire retardant particles. The fire retardant material may be substantially evenly distributed therethrough. Distribution of the fire retardant material through the resiliently deformable material improves the fire-resistance of the seal because each discrete element of the fire-retardant material may have space around it to expand into when heated by fire.

The impregnated fire-retardant material may be graphite-based.

A second aspect of the invention provides a fire assembly comprising: a) a fire seal according to the first aspect; b) a first structural member having an internal face; c) a second structural member having an intemal face; and wherein the internal face of the first structural member opposes the intemal face of the second structural member such that a gap is defined between the two faces, the seal being deformed into the gap and mechanically held in place, e.g. by the resilient expansion of the seal.

The first end of the seal may be dimensioned to be wider than the gap between the two opposing internal faces of the structural members. This ensures that the seal cannot be lost into the gap during installation; the first end will always stick out, enabling the seal to be easily removed again if required.

The assembly may further comprise an architrave positioned over the first end of the seal. The arehitrave may comprise a channel dimensioned to have a substantiafly similar width to the first end of the seal, such that the architrave can be easily fitted over the seal.

The seal may extend entirely along the length of the gap between the two opposing internal faces of the structural members. This advantageously seals the entire gap, draught-proofing the gap and preventing smoke from passing through during a fire.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a schematic view of a door frame installed in a door opening formed in a building wall fitted with a fire seal according to an embodiment of the present invention; Figure 2 is a cross-sectional view taken along line Il-Il in Figure 1; Figure 3 is a cross-section through a door frame and building wall fitted with a fire seal according to an embodiment of the present invention; Figure 4 is a cross-section of the fire seal from Figure 2; Figure 5 is an isometric view of a fire seal assembly according to an embodiment of the present invention; Figure 6 is a cross-sectional view of the fire seal assembly of Figure 5, further including an architrave according to an embodiment of the present invention; and Figures 7 to 11 show alternative cross-sections for alternative embodiments of fire seals.

DETAILED DESCRIPTION OF EMBODIMENT(S)

Figure 1 shows a building waH 20 in which is formed a door opening 21. A door frame 24 is shown mounted in the door opening 21; the frame 24 including a pair of spaced upright frame members 26, 27 and a bridging top frame member 28.

Although not visible in Figure 1, there is a gap between respective frame members 26, 27 and 28 and the wall edge face which defines the door opening 21. The gap extends completely around the door frame 24. In accordance with the present invention, this gap is sealed by a fire seal 30.

Referring now to Figures 1 and 2, the gap between frame member 26 and the wall edge face 20a is visible in Figure 2 and is designated by reference number 29. A similar gap is defined between respective frame members 27, 28 and opposed wall edge face 20a and so the following description relating to the sealing of frame member 26 also applies to frame members 27, 28.

The gap 29 has a first open mouth 31 located adjacent to one side face 26a of frame member 26 and a second open mouth 32 located adjacent to its opposite side face 26b.

The frame member 26 is typically secured to the edge face 20a of the wall using a number of screws (not shown), and wooden or plastics packers (not shown) are place in the gap 29 around the screws, to ensure the frame is not distorted following installation. The packers may be of variable size, and in some instances may be at or near the mouths 31 and/or 32 of the gap 29.

A fire seal 30 of an embodiment of the present invention is shown fitted on either side of the door frame in order to seal off both mouths 31, 32. This is the preferred arrangement (ie. sealing off both mouths 30, 31) but it will be appreciated that only one mouth 31 or 32 may be sealed off as desired. The construction of seal 30 is described in more detail below. It will be appreciated that as illustrated in Figure 2, the seal is in a partly compressed, fitted state and is therefore a different shape from the relaxed, unfitted state shown in Figure 4 (described later).

In use, the seal 30 is pushed into the gap 29 to seal it along fts entire length. It is pushed in as far as it will go and is then held in place mechanically by the internal surfaces 20a, 20b of the gap 29. No form of adhesive is required to hold it in place. It can also be removed easily if desired.

The width of the gap 29 to be sealed is Wg. In practice, when fitting door frames into building wall openings the size of the door frame 24 is approximately that of the opening less a working tolerance. Accordingly, in most circumstances it is known that the gap width Wg will be within a known tolerance.

The seal 30 has a maximum width dimension Ws, which is greater than the generally accepted maximum gap width Wg, such that during installation the seal cannot be pushed into the gap 29 too far and get lost.

Figures 3 and 4 show the profile of the seal 30 in more detail. Figure 3 shows the seal in a partly compressed, fitted state, and Figure 4 shows the seal in a relaxed, unfitted state. Firstly, referring to Figure 4, the profile of the seal in a relaxed, unfitted state is substantially symmetrical along a central longitudinal axis A-A, with a fir st end 52 and a second end 54. The first end has a width Ws, which is chosen to be greater than the width of the gap Wg that the seal is to be inserted into. By way of example only, 15mm is an appropriate width Ws.

The second end 54 has a narrower width than the first end 52, so the seal profile is generally wedge-shaped. The width of the second end 54 is narrower in order to enable the seal to be inserted into gaps with a very narrow width Wg. For illustration only, and to give an impression of the scale of the seal, an appropriate width of the second end 54 is 2mm and the longitudinal distance from the first end 52 to the second end 54 is 25mm. In other embodiments, it will be appreciated that these dimensions may be varied as required and a range of sizes may be offered to fill gaps of varying sizes.

Two outer faces 56 extend from the first end 52 to the second end 54. In this embodiment, each outer face 56 is divided into a first portion 58 and a second portion The first portion 58 and second portion 60 are planar surfaces. The planar surfaces are angled such that an angle between the longitudinal axis A-A of the seal 30 and the planar surface of the first portion 58 is greater than an angle between the longitudinal axis A-A and the planar surface of the second portion 60. As an example, in this embodiment, the angle between the first portion 58 and the longitudinal axis A-A is approximately 23°, and the angle between the second portion 60 and the longitudinal axis A-A is approximately 6°.

The seal of Figure 4 is symmetrical about the longitudinal axis A-A, but alternatively, the seal may not be symmetrical.

Referring now to Figure 3, it can be seen that when the seal 30 is inserted into a gap 29, the seal is deformed locally where the seal contacts an edge of the door frame member and an edge of the wall. In this embodiment, the seal is generally un-deformed in areas outside the region of localised deformation.

It can aslo be seen from Figure 3 that when the seal 30 is inserted into the gap 29, an angle is created between the internal side faces 20a and 20b, and the first portion 58 and the second portion 60. The angle between the internal side face 20a and the first portion 58 is steeper than the angle between the internal side face 20a and the second portion 60. This also applies to the angle between the opposite first portion 58 and the internal side face 20b and the opposite second portion 60 and the internal side face 20b.

As the angle between the second portion 60 and the longitudinal axis A-A is small, the seal can be fitted in narrow gaps with a relatively low insertion force, but still be securely held in place mechanically. Additionally, a larger angle between the first portion 58 and the longitudinal axis A-A ensures that a part of the outer edge 56 is still in contact with a structural member even when the gap 29 is wider, without the seal 30 being too bulky, and to rcducc the ehanec of accidental over-insertion.

It will be appreciated that the face 56 can be of any shape, provided it joins the first end 52 to the second end 54. Figures 7 to II show examples of alternative shapes of seals 30b, 30e, 30d, 30e, and 30 For example, the seal may have a convex portion as shown in Figure 7, or a concave portion as shown in Figure 10. The seal may have a curved profile undulating along a generally tapered profile of the seal, as shown in Figure 8. The seal may comprise a lip at the first end of the seal as shown in Figure 9.

The seal may comprise a profile having barbs positioned to ease insertion in a gap but resist removal of the seal from the gap, as shown in Figure 11. Alternatively, the seal may have any appropriate combination of the these features.

As shown in Figure 5, the seal 30 is elongate, with a constant profile along its length.

This ensures that it is able to fill the entire length of the gap 29. In alternative embodiments, the profile may be varied along the length of the seal.

The seal 30 is preferably manufactured by a co-extrusion process, which advantageously leaves smooth outer surfaces for ease of installation. Alternatively, the seal 30 could be manufactured in other ways, for example cutting or moulding.

In this embodiment, the seal is formed from an elastomerie foam with a closed cell structure, which comprises nitrile rubber. The applicants have found a closed cell foam to be preferable to an open cell foam, as it more readily retains the compressed shape without a tendency to work its way out of the gap by re-expanding.

The foam is also impregnated with a fire-retardant material, in this case a graphite-based fire-retardant particles. Tn the event of afire, the graphite may intumesee to a certain extent, i.e. expanding into the gap further.

Although this material has properties that make it ideal for use in this application, it will be appreciated that other materials may be used provided they have similar properties (resiliently deformable, easily extruded etc.), for example a flexible plastic.

In the present embodiment the seal is formed as a substantially solid body (i.e. the only vacant areas are formed by the cells of the foam), alternatively, the seal may be formed a hollow body.

Tn the present embodiment, the fire-retardant material is impregnated in the foam material as part of the mixture, prior to extrusion unlike the solid core or protruding section of the prior art. This means that the fire-retardant material is substantially evenly distributed throughout the material, giving the seal a good fire resistance. In addition

TO

Although tire resistance is its primary function, the seal typically also inhibits the transmission of smoke and acts as a sound attenuator.

Referring now to Figure 6, a fire seal of the presently described embodiment is shown in use in an installation. In addition to the fire seal 30, the installation includes first structural member, in this ease a door frame 26, a second structural member, in this ease a wall 20, and preferably an arehitrave 60, to cover the seal.

The arehitrave 60 is a strip of material dimensioned so as to cover the length of the gap 29 and hide the seal 30. Its profile comprises a channel 62 that is continuous throughout the entire length of the arehitrave 60. The channel 62 is dimensioned to fit over the first end 52 of the seal 30 as it protrudes out of the gap 29. Tn use, the architrave 60 is pushed into contact with the outer surfaces of the first and second structural members 22, 26a with the channel 62 accommodating the first end 52 of the seal 30 that protrudes out of the gap 29. The architrave 60 may be adhesively attached to the structural members 20, 26 by, for example, contact adhesive, or pinned using nails/panel pins. If the seal 30 has been inserted into a gap at the narrow end of its range of functionality, then protruding excess material may in some circumstances be cut from the seal, e.g. using a sharp blade, to enable the arehitrave 60 to be fined.

Where packers have been used in the gap 29, if they are recessed from the mouth of the gap the seal 30 may fit over the top without interruption. If however the packer is at or near the mouth, it may be necessary to cut the seal and space it so it does not fit over the packer. In other words, there may be more than one length of seal in the gap, separated by the or each packer, but the combination of the seal and the packers acts to block the potential routes for transmission of fire.

The embodiments described above have been described in relation to a door frame installation; it will be appreciated that the seal according to the present invention may be used for other installations, such as window frame or internal wall partition installations.

Further, although the invention has been described above with reference to one or more preferred embodiments, it will be appreciated that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

Claims I. A fire seal for sealing a gap between opposing faces of first and second structural members, the fire seal comprising: a first cnd and a sccond end, thc first cnd bcing dimensioned so as to bc widcr than the second end, and a generally tapcrcd profile cxtending between thc first cnd and thc second cnd, and wherein the fire seal is formed from a resiliently deformable material and a fire-retardant material, such that, in use, the fire seal can be deformed into a gap between opposing faccs of a first and sccond structural mcmbcr and once in position is mechanically held in place.
2. A fire seal according to claim 1, wherein the profile of the seal decreases in width at a non-constant rate from the first end to the second end.
3. A fire seal according to any previous claim, wherein the profile of the seal has at least one planar face.
4. A fire seal according to claim 3, wherein at least one side of the profile comprises a first planar face and a second planar face, and wherein an angle between the first planar face and a longitudinal axis of the seal extending the length of the seal from the first end to the second end is greater than an angle between the second planar face and the longitudinal axis.
5. A fire seal according to any one of the previous claims, wherein the seal compriscs a lip that extends from the tapered profile at the first end.
6. A fire seal according to any one of the previous claims, wherein the seal is integrally formed, e.g. by extrusion.
7. A fire seal according to any previous claim, wherein the seal is elongate and comprises a substantially constant profile along its length.
8. A fire seal according to any previous claim, wherein the resiliently deformable material is a foam.
9. A fire seal according to claim 8, wherein the resiliently deformable material is an elastomcric foam.
10. A fire seal according to claim 8 or claim 9 wherein the resiliently dcformablc material is a closed cell foam.
11. A fire seal according to claim 10 wherein the resiliently deformable material comprisics nitrile rubber.
12. A fire seal according to any previous claim, wherein the fire retardant material is impregnated into the resiliently deformable material so as to be distributed therethrough.
13. A fire seal according to any previous claim, wherein the fire-retardant material is graphite-based.
14. A fire seal assembly comprising: a) a fire seal according to any one of the previous claims; b) a first structural member having an internal face; c) a second structural member having an internal face; and wherein the internal face ofthe first structural member opposes the internal face of the second structural member such that a gap is defined between the two faces, the seal being deformed into the gap and mechanically held in place..
15. A fire seal assembly according to claim 14 further comprising an architrave positioned over the first end of the seal.
16. A fire seal assembly according to claim 14 or 15, whercin the seal extends substantially entirely along the gap between the two opposing internal faces of the structural members.
17. A fire seal substantially as hereinbeibre described with reference to and/or as shown in the accompanying drawings.
18. A fire seal assembly substantially as hereinbcfore described with reference to and/or as shown in the accompanying drawings.