WO2010096022A1

WO2010096022A1 - Fire door and fire door assembly

Info

Publication number: WO2010096022A1
Application number: PCT/SG2010/000033
Authority: WO
Inventors: Hoong Thye Eldon Lee
Original assignee: Hoong Thye Eldon Lee
Priority date: 2009-02-18
Filing date: 2010-02-03
Publication date: 2010-08-26
Also published as: TW201033453A; SG164295A1

Abstract

There is provided a fire door comprising a core panel for the door and a peripheral framework surrounding the core panel. The peripheral framework comprises a left stile and a right stile parallel to each other and extending along the length of the core panel, and an upper rail and a lower rail parallel to each other and extending along the width of the core panel. At least one of the stiles or rails comprises at least one strip of fire-stop material.

Description

FIRE DOOR AND FIRE DOOR ASSEMBLY

FIELD OF INVENTION

The invention relates to a fire door, and in particular, to a fire door having a core panel for the door and a peripheral framework surrounding the core panel. The fire door may advantageously possess acoustic properties, i.e. acoustic fire door. The invention also relates to a fire door assembly consisting of a pair of coupling fire door and door frame.

BACKGROUND TO THE INVENTION

The following discussion of the background to the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was published, known or part of the common general knowledge in any jurisdiction as at the priority date of the application.

In compliance with fire safety regulations, fire doors are usually given a fire-rating for an intended purpose. For example, a fire-rating of 30 is used to indicate that the fire door, if installed correctly, will maintain its structural integrity and provide a barrier to fire, heat and/or smoke for at least 30 minutes. There are circumstances where higher fire-rated fire doors are desired. For instance, a fire door installed in a public building requires a higher fire-rating to allow more time for people to escape or to allow more time for help to arrive compared to a fire door installed in a private home.

Conventional fire doors consist of timber-finished or metal-clad core panels and solid timber peripheral frameworks surrounding the core panels. The fire doors are hinged at one side so that they could be easily swung open or closed. Such fire doors typically are fixed with locks so that the doors may remain in a closed position. Advantageously, these fire doors are further provided with closers with self-closing facilities to forcefully close the doors when required, particularly in the event of a fire outbreak. Fire doors typically weigh around 40-80 kg and are 2,100 mm high, 1 ,000 mm wide and 45-50 mm thick. Accordingly, the thickness of the peripheral framework surrounding the core panel of the fire door may be 25-50 mm at the minimum. In certain circumstances such as when locks and closers are required to be installed, the thickness of the peripheral framework at the locks and closers locations may be 75-150 mm. For aesthetic purposes, fire doors including the core panels and the peripheral frameworks may be laminated or overlaid on both faces of the fire doors with plywood, veneer, or the like (i.e. door skins) to enhance the appearance of the fire doors. For such laminated fire doors, the thicknesses of the core panel and the peripheral framework are reduced to 36-42 mm. And with these reduced peripheral framework thickness, solid timber of hardwoods such as kapur, balau and chengal having high densities around 700-900 kg/m³ are needed in order to provide for a fire door with a fire-rating of 30, at the minimum. Hardwoods having such high densities are costly and are becoming scarce in availability.

Figures 1A, 1 B and 1C illustrate a fire door commonly known in the art. Figure 1A shows the front view of a conventional fire door. The fire door consists of a rectangular core panel and a peripheral framework surrounding the core panel. As mentioned previously, fire doors are hinged at one side and are preferably fixed with closers and locks. The hinges are located at one side of the fire door while the lock is located at the opposing side along the same face of the fire door. The closer is located at the top edge of the fire door. The locations of the hinges, closer and lock are illustrated in Figure 1 B. At locations where hinges are to be fixed, prior to installing hinge screws, it is a preferred and common practice to wrap these locations with perforated steel plates (also commonly known as metal box shoe having a C- shape) to spread the stress points/loads of the hinge screws evenly over a wider area. This manner of installing the hinge screws works well especially for fire doors weighing up to 80 kg.

Figure 1C illustrates the top view of the fire door taken from the cross-section along the A-A line. The fire door is shown to abut a door frame rebate when the fire door is closed. Typically the door frame rebate is 20 mm wide to allow a portion of the fire door to abut. Existing fire doors comprise edge strip timber stiles each of about 10 mm wide. The stiles and the core panels sandwich the perforated steel plates therebetween.

It is often encountered that during the onsite installation of the fire doors, portions of the stiles are required to be trimmed to fit within the door frames. With approximately 10 mm width of timber stile on each side of the fire door, trimming of the stile beyond 10 mm is not recommended since doing so will mean cutting into the perforated steel plates and therefore compromising the integrity of the fire door. Increasing the width of the stile beyond 20 mm while maintaining the overall width of the fire door (i.e. reducing the width of the core panel) to account for such subsequently trimming is also not recommended. The door frame rebate is usually 20 mm wide and during the complete burnt-out of the stile, the fire door will no longer abut the door frame rebate and a gap will exist between the door frame and the core panel, thereby allowing fire to spread through the gap.

To improve the fire-resistance of the fire door system, a fire seal such as an intumescent having a thickness of 2-4 mm, is placed at the exposed edge of the door frame rebate or at the exposed edge of the stile or both. This is illustrated in Figure 1 D. In this way, when there is a fire outbreak, heat will cause the fire seal to expand in the direction away from the exposed edge of the door frame rebate towards the stile or from the exposed edge of the stile towards the door frame rebate. The movement of the fire seal acts to close or narrow the gap between the door frame rebate and the stile to prevent the spread of fire through the gap. However, as highlighted previously, if trimming of the stile is required, there exists the risk of accidental removing of the thin strip of the fire seal placed at the exposed edge of the stile.

As material costs increase over the recent years due to the depletion of resources, the thickness of the core panel of the fire door and therefore the thickness of the peripheral framework (stiles and rails) may be reduced, say, from 54 mm to 45 mm. Accordingly, the thickness of the door frame rebate will have to be adjusted to match the thickness of the stile. With a reduced thickness in the door frame rebate and stile, the amount of fire seal placed at the exposed edge of the door frame rebate or at the exposed edge of the stile or both will be reduced. As illustrated in Figure 1 E, fire may burn through portions of the door frame rebate where there is no fire seal and spread over to the other side of the fire door.

Therefore, it is desirable to provide for a fire door and a fire door system that overcomes, or at least alleviates, the above problems.

SUMMARY OF THE INVENTION

Throughout this document, unless otherwise indicated to the contrary, the terms "comprising", "consisting of, and the like, are to be construed as non-exhaustive, or in other words, as meaning "including, but not limited to". In a first aspect of the present invention, there is provided a fire door comprising a core panel for the door and a peripheral framework surrounding the core panel. The peripheral framework comprises a left stile and a right stile parallel to each other and extending along the length of the core panel, and an upper rail and a lower rail parallel to each other and extending along the width of the core panel. At least one of the stiles or rails comprises at least one strip of fire-stop material.

BRIEF DESCRIPTION OF THE DRAWINGS

In the figures, which illustrate, by way of example only, embodiments of the present invention,

FIG. 1 A shows a front view of a prior art fire door and door frame.

FIG. 1 B shows an isometric view of a prior art core panel.

FIG. 1C shows a top view of the fire door and the door frame of FIG. 1A taken from the cross-section along the A-A line.

FIG. 1D shows a top view of the fire door and the door frame of FIG. 1A taken from the cross-section along the A-A line with fire seals placed either in the fire door or the door frame.

FIG. 1 E shows a top view of the fire door and the door frame of FIG. 1 A taken from the cross-section along the A-A line when both the thicknesses of the fire door and the door frame are reduced, and the spread of fire through the reduced thicknesses. FIG. 2 shows a front view of a fire door and door frame in accordance with one aspect of the invention.

FIG. 3A-3F show a top view of the left stile and the core panel taken from the cross-section along the B-B line in FIG. 2.

FIG. 4A and 4B show a top view of the fire door and the door frame as illustrated in FIG. 3D and 3A, respectively.

FIG. 5 shows parts of the peripheral framework, specifically the upper rail, the lower rail and the right stile connecting the upper rail and the lower rail.

FIG. 6A-6H show the top view of the door frame and the door frame rebate taken from the cross-section along the B-B line in FIG. 2.

FIG. 7A-7D show the cross-section taken along the line B-B of FIG. 2, except that the fire door is now double-leaf type or double-swing type.

FIG. 8A-8C show alternative arrangements of the stile when non-combustible facings are provided on each side of the fire door face.

DETAILED DESCRIPTION

The invention relates to a fire door having a core panel for the door and a peripheral framework surrounding the core panel. In particular, the peripheral framework is fire-resistant. The fire door may advantageously possess acoustic properties, i.e. acoustic fire door. The invention also relates to a fire door assembly consisting of a pair of coupling fire door and door frame. In particular, the door frame is fire-resistant.

In accordance with a first embodiment of the invention illustrated in FIG.2, there is provided a fire door 10 comprising a core panel 12 for the door and a peripheral framework 14 surrounding the core panel 12. The peripheral framework 14 comprises a left stile 16 and a right stile 18 parallel to each other and extending along the length of the core panel 12, and an upper rail 20 and a lower rail 22 parallel to each other and extending along the width of the core panel 12. At least one of the stiles 16, 18 or rails 20, 22 comprises at least one strip of fire-stop material 24. The fire-stop material 24 may be a fire-rated gel, glue, graphite-based strip, palusol, or other materials having fire-stopping properties.

The core panel 12 for the fire door 10 may be prior art fire-resistant core panel and may be a lightweight set and hardened material based on cement and/or gypsum. Lightweight characteristics can be achieved by having large voids in the core panel 12 but are more preferably achieved by suitable choice of lightweight, natural or synthetic, particulate or fibrous, fillers, additives and aggregates, and/or the intentional incorporation of small air voids, as a set and hardened air-entrained or aerated materials. The core panel 12 may also be configured with strengthened portions to accept hinge connections, locks and door closers, and the faces of the core panel 12 can be suitably clad with plywood, veneer, decorative papers or metal sheets to improve appearance. For a more detailed description of the core panel 12, reference is made to United Kingdom Patent No. 2266912B granted on 15 January 1997, whose description and drawings are hereby incorporated by reference. Other types of fire-resistant core panels apparent to persons skilled in the art are also suitable.

A top view of the left stile 16 and the core panel 12 taken from the cross-section along the B-B line in FIG. 2 is illustrated in FIG. 3A-3F. Various arrangements of the fire-stop material 24 are shown. In FIG. 3A, a strip of the fire-stop material 24 is sandwiched between two pieces of timber blocks 16A, 16B. Two pieces of timber blocks 16A, 16B sandwiching the fire-stop material 24 forms the left stile 16. Similar arrangements are shown in FIG. 3B-3C. In FIG. 3B, two strips of fire-stop materials are sandwiched between three timber blocks 16A, 16B, 16C. The first strip of fire- stop material 24A is sandwiched between timber block 16A and timber block 16C. The second strip of fire-stop material 24B is sandwiched between timber block 16C and timber block 16B. In FIG. 3C, three strips of fire-stop materials are sandwiched between four timber blocks 16A, 16B, 16C, 16D. The first strip of fire-stop material 24A is sandwiched between timber block 16A and timber block 16C. The second strip of fire-stop material 24B is sandwiched between timber block 16C and timber block 16D. The third strip of fire-stop material 24C is sandwiched between timber block 16C and timber block 16D. It is to be appreciated that any number of strips of fire- stop materials and corresponding number of timber blocks may be possible. Further, the timber blocks 16A, 16B, 16C, 16D may be of equal thickness or otherwise. Similarly, the fire-stop materials 24A, 24B, 24C may be formed of the same material or otherwise.

For simplicity, the blocks 16A, 16B, 16C, 16D forming the left stile 16 are all made of timber, hence termed as timber block herein. It is to be appreciated that blocks formed of other materials are also suitable. For example, in FIG. 3B, the outer blocks 16A, 16B are timber while the inner block 16C could be MDF, particleboard or hardboard. Alternatively, the inner block 16C could be timber while the outer blocks 16A, 16B could be fibreboard or plastic/wood.

The strip of fire-stop material 24 should preferably be as thin as possible in order to provide a larger area available for hinging screws to be fixed in the timber blocks, for instance. The fire-stop material 24 may be soft and will not provide good screw holding if screws are installed through the strip of fire-stop material 24. By reducing the thickness of the strip of fire-stop material 24, the likelihood of a hinging screw being installed through the strip of fire-stop material 24 is lowered. This is particularly useful and advantageous where good screw holding and ease of use are highly desired. As an illustration, for a 40 mm thick stile, a 2 mm thin strip of fire-stop material (e.g. palusol) will achieve the same fire-rating as a 6 mm calcium silicate.

The blocks 16A, 16B, 16C, 16D and the strip of fire-stop material 24 may be sandwiched by conventional methods known to persons skilled in the art. For example, strips of fire-stop material such as intumescents may be laminated onto the stiles or rails using adhesives or glue. Advantageously, the lamination could be reinforced with mechanical attaching means such as small pins, nails and screws for stronger holding for stiles and rails formed of gypsum, magnesium oxide, cement, calcium silicate, ceramic fibres, ceramic tapes, and other boards of powdery nature. Such stiles and rails do not expand to give thermal insulation. Instead, thermal insulation is provided for by the intumescents. Intumescents expand during a fire outbreak due to the heat. The intumescents expand to take up the space left void by portions of the charred/burnt stiles and rails. During the expansion, the stiles and rails tend to be pushed apart thereby leading to failure mode. The stiles and rails may be prevented from falling apart by the small pins, nails and screws holding the stiles and rails in place thereby preserving integrity of the stiles and rails. Alternative arrangements are shown in FIG. 3D-3F, where at least two strips of fire-stop material 24A, 24B, 24C are disposed within the left stile 16. The strips of fire-stop material 24A, 24B, 24C are inter-dispersed forming an interdigital-spaced arrangement. The strips of the fire-stop material 24A, 24B, 24C may extend from one end to the other end along the entire width of the left stile 16 (i.e. FIG. 3B-3C), or extend from one end and stop abruptly along the width of the left stile 16 illustrated in FIG. 3D-3F. In such circumstances where the strips of fire-stop material 24A, 24B, 24C stop abruptly, the amount of overlap between strips of fire-stop material 24A, 24B, 24C and the distance between strips of fire-stop material 24A, 24B, 24C will depend on the types of material used for the timber block and the fire-rating required. For example, if a high fire-rating is required, the amount of overlap between strips of fire- stop material 24A, 24B, 24C should be more than that needed for a lower fire-rating, and/or the distance between strips of fire-stop material 24A, 24B, 24C should be narrower than that needed for a lower fire-rating. Similarly, lesser overlap between strips of fire-stop material 24A, 24B, 24C and/or narrower distance between strips of fire-stop material 24A, 24B, 24C is required for a higher density stile 16 than a lower density one.

Besides being disposed within the left stile 16, the strip of fire-stop material 24 may be disposed on the outer face of the left stile 16 (not shown) and may subsequently be suitably clad with plywood, veneer, decorative papers or metal sheets to improve the overall appearance of the fire door 10. In addition, non- combustible facings may be used to clad the outer face of the fire doors.

FIG. 4A shows the arrangement of the embodiment of the strips of fire-stop material 24A, 24B in FIG. 3D when the fire door 10 abuts the door frame 40 at the door frame rebate 34. Likewise, FIG. 4B shows the arrangement of the embodiment of the strips of fire-stop material 24 in FIG. 3A when the fire door 10 abuts the door frame 40 at the doorframe rebate 34.

The arrangement and the amount of fire-stop material 24 may depend on the fire- rating desired. For instance, for lower fire-rated fire doors, a thin strip of fire-stop material 24, say 0.5 mm, extending along the entire width of the left stile 16 may be sufficient. For higher fire-rated fire doors, at least three blocks 16A, 16B, 16C sandwiching at least two strips of fire-stop material 24 are required. Other suitable materials and arrangements for the blocks and stile apparent to person skilled in the art are also possible. Further, similar to prior art stiles, fire seals 36 may be provided on the exposed edge of the left stile 16.

FIG. 5 shows parts of the peripheral framework 14, specifically the upper rail 20, the lower rail 22 and the right stile 18 connecting the upper rail 20 and the lower rail 22. At locations where a closer 30 and a lock 32 are to be fixed, a closer block 26 and a lock block 28 are provided. The closer block 26 may stem from the upper rail 20 or may be a separate piece attached to the upper rail 20. The closer block 26 may have the same fire-stop material 24, the same arrangement and may be formed of the same materials of the upper rail 20. The purpose of the closer block 26 is to provide a larger area for the attachment by screws, for example, of the closer 30 since the closer 30 will most likely be fixed at a location away from the edge of the upper rail 20. In a similar manner, the lock block 28 may stem from the right stile 18 or may be a separate piece attached to the right stile 18. The lock block 28 may have the same fire-stop material 24, the same arrangement and may be formed of the same materials of the right stile 18. The purpose of the lock block 28 is to provide a larger area for the attachment by screws, for example, of the lock 32 since the lock 32 will most likely be fixed at a location away from the edge of the right stile 18.

In certain circumstances, besides providing the fire-stop material 24 in the stiles or rails, it may be advantageous to simultaneously provide the fire-stop material 24 in the door frames 40, especially wooden door frames 40 that may be burnt-out by fire. Firstly, this will provide a higher fire-rating for the fire door assembly comprising the fire door 10 and the door frame 40. Secondly, in the event that the stile of the fire door 10 needs to be trimmed in order to fit within the doorframe 40 and the trimming is such that very little or no fire-stop material 24 is left in the left stile 16, at least the fire-stop material 24 in the doorframe 40 will act against the spread of fire during a fire outbreak.

FIG. 6 shows the top view of the door frame 40 and the door frame rebate 34 taken from the cross-section along the B-B line in FIG. 2. Similar to prior art door frames, fire seals 36 may be provided at the exposed edge of the door frame rebate 34. In FIG. 6A, the strip of fire-stop material 24 extends along the width of the door frame rebate 34 from one end of the door frame rebate 34 where the fire seal 36 is located and stops abruptly before reaching the other end of the door frame. In FIG. 6B-6D, the strip of fire-stop material 24 is disposed near to one end of the fire seal 36. Similar to the arrangements for the strips of fire-stop material 24 disposed in the stile 16 described in FIG. 3A-3F, it is possible to provide two or more strips of fire- stop materials 24A, 24B, 24C in the door frame rebate 34. And the two of more strips of fire-stop material 24A, 24B, 24C may be inter-dispersed forming an interdigital- spaced arrangement as illustrated in FIG. 6E-6H. Likewise, in circumstances where the strips of fire-stop material 24A, 24B, 24C stop abruptly, the amount of overlap between strips of fire-stop material 24A, 24B, 24C and the distance between strips of fire-stop material 24A, 24B, 24C will depend on the types of material used for the door frame rebate and the fire-rating required.

Besides the single-leaf door illustrated in FIG. 2, it is possible to provide fire doors comprising of double-leaf. FIG. 7A shows the cross-section taken along the line B-B of FIG. 2, except that the fire door is now double-leaf type. Portions of the double-leaf fire door 10 in a closed position is shown in FIG. 7A. The left side of the double-leaf fire door is shown to comprise core panel 12A and stile 16A. The right side of the double-leaf fire door 10 is shown to comprise core panel 12B and stile 16B. The arrangement of the strips of fire-stop material 24A-24D may be similar to that described for the single-leaf fire door 10 and may be be inter-dispersed forming an interdigital-spaced arrangement. Since there exists a gap between the left side and right side of the double-leaf fire door 10 when in a closed position Qust like there exists a gap between the fire door 10 and the door frame rebate 34 when the fire door 10 abuts the door frame rebate 34 in a closed position), it is preferred to provide for fire seals 36A, 36B at each exposed edge of the left side and right side of the double-leaf fire door 10 so that the fire seals 36A, 36B expand during a fire outbreak to narrow the gap between the left side and right side of the double-leaf fire door 10. The arrangements of the fire seals 36 and strips of fire-stop material 24 are also possible for double-swing type fire doors 10 as shown in FIG. 7B. The double-leaf fire door 10 and double-swing fire door 10 may be timber-exposed at the stiles as shown in FIG. 7A and FIG. 7B, respectively. Alternatively, the double-leaf fire door 10 and double-swing fire door 10 may be ply-covered, for example, at the stiles as shown in FIG. 7C and FIG. 7D, respectively. It is to be appreciated that configurations of fire doors other than the above described single-leaf, double-leaf and double-swing types are also possible.

In further embodiments shown in FIG. 8A-8C, non-combustible facings 42 are provided on each side of the fire door face. Non-combustible facings 42 such as gypsum, magnesium oxide, cement, calcium silicate, ceramic fibres, ceramic tapes and other materials apparent to persons skilled in the art may be used. When non- combustible facings 42 are used, it is possible to re-orientate the peripheral framework 14 to increase the screw holding to improve the integrity of the fire door during a fire outbreak. In FIG. 8A, the stile 16 comprises a single block of timber, for example. The stile may comprise more than one block 16A, 16B, 16C and may be formed of different materials. In FIG. 8B₁ the stile 16 comprises two blocks 16A, 16B of different materials such as timber and ceramic. In FIG. 8C, the stile 16 comprises three blocks 16A, 16B, 16C of different materials such as alternating blocks of timber and ceramic. The exposed edge of the stile may optionally be covered with timber, for example. Other configurations of the blocks 16A, 16B for the stile are also possible.

The afore-described fire door and fire door assembly provides several advantages, other than those described previously. Firstly, with the possible use of blocks of different materials for the stiles and rails, lesser quantity of high densities timber may be used. As mentioned previously, hardwoods having densities around 700-900 kg/m³ are required for use as fire doors if no fire-stop materials are used. With the present fire door and fire door assembly, lower densities woods may be employed. Indeed, with the scarcity of hardwoods in recent years, substitutes such as MDF, high glue particleboard, PVC/wood dust extrusions, hardboards, ceramic board, and the like may be used so long as such substitutes are capable of holding screws, being worked such as cutting, trimming and planing, and have timber-like properties. Secondly, by having lighter and low densities materials forming the stiles and rails, and including the lightweight core panel, the entire fire door becomes more stable with less twists and warps, thereby preserving the integrity of the fire door.

Thirdly, by having the fire-stop material extending from the exposed edge and along the width of the peripheral framework (be it stile or rail), the risk of removing the entire strip of fire-stop material during trimming is minimized.

Fourthly, by having different blocks for the stiles and rails instead of a unitary piece of stile or rail, besides sandwiching strips of fire-stop material, it is possible to sandwich sound-insulating materials such as rubber sheets, silicone sheets, foamed rubber, felt, ceramic fibre and thin plywood as separators to thereby form fire doors having acoustic properties, i.e. acoustic fire doors. Other vibration absorbing materials and sound dampening materials may also be suitable.

Further, the different blocks may be easily assembled or joined. Common joint techniques include butt and finger joints. In cases where moulders are available, grooves may be cut at strategic locations on the peripheral framework and the fire- stop material inserted into the grooves. The present fire door and fire door assembly therefore provides for a simple way of achieving high fire-ratings.

Although the foregoing invention has been described in some detail by way of illustration and example, and with regard to one or more embodiments, for the purposes of clarity of understanding, it is readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes, variations and modifications may be made thereto without departing from the spirit or scope of the invention as described in the appended claims. Similarly, discussions relating to the left stile may be applicable to the right stile, and the upper rail to the lower rail.

Claims

CLAIM:

1. A fire door comprising:

• a core panel for the door; and

• a peripheral framework surrounding the core panel, the peripheral framework comprising a left stile and a right stile parallel to each other and extending along the length of the core panel, and an upper rail and a lower rail parallel to each other and extending along the width of the core panel;

wherein at least one of the stiles or rails comprises at least one strip of fire-stop material.

2. The fire door recited in claim 1 , wherein the at least one strip of fire-stop material extends along the length of the stiles or rails.

3. The fire door recited in claim 1 or 2, wherein the at least one strip of fire-stop material transverse across the width of the stiles or rails.

4. The fire door recited in any one of claim 1 , 2 or 3, wherein the at least one strip of the fire-stop material is disposed within the stiles or rails.

5. The fire door recited in any one of claim 1 , 2 or 3, wherein the at least one strip of the fire-stop material is disposed on at least one outer surface of the stiles or rails.

6. The fire door recited in any one of the preceding claims, wherein the stiles or rails is one of: timber; balau; chengal; gypsum; magnesium oxide; cement; calcium silicate; particle board; oriented strand board (OSB); medium-density fibrewood (MDF).

7. The fire door recited in any one of the preceding claims, wherein the fire-stop material is one of: gel; glue; graphite-based strip; palusol; intumescent.

8. A stile suitable for use in a fire door, the stile comprising at least one strip of fire-stop material.

9. The stile recited in claim 8, wherein the at least one strip of fire-stop material extends along the length of the stile.

10. The stile recited in claim 8 or 9, wherein the at least one strip of fire-stop material transverse across the width of the stile.

11. The stile recited in any one of claim 8, 9 or 10, wherein the at least one strip of the fire-stop material is disposed within the stile.

12. The stile recited in any one of claim 8, 9 or 10, wherein the at least one strip of the fire-stop material is disposed on at least one outer surface of the stile.

13. The stile recited in any one of claim 8 to 12, wherein the stile is one of: timber; balau; chengal; gypsum; magnesium oxide; cement; calcium silicate; particle board; oriented strand board (OSB); medium-density fibrewood (MDF).

14. The stile recited in any one of claim 8 to 13, wherein the fire-stop material is one of: gel; glue; graphite-based strip; palusol; intumescent.

15. A rail suitable for use in a fire door, the rail comprising at least one strip of fire- stop material.

16. The rail recited in claim 15, wherein the at least one strip of fire-stop material extends along the length of the rail.

17. The rail recited in claim 15 or 16, wherein the at least one strip of fire-stop material transverse across the width of the rail.

18. The rail recited in any one of claim 15, 16 or 17, wherein the at least one strip of the fire-stop material is disposed within the rail.

19. The rail recited in any one of claim 15, 16 or 17, wherein the at least one strip of the fire-stop material is disposed on at least one outer surface of the rail.

20. The rail recited in any one of claim 15 to 19, wherein the rail is one of: timber; balau; chengal; gypsum; magnesium oxide; cement; calcium silicate; particle board; oriented strand board (OSB); medium-density fibrewood (MDF).

21. The rail recited in any one of claim 15 to 20, wherein the fire-stop material is one of: gel; glue; graphite-based strip; palusol; intumescent.