GB2347712A

GB2347712A - Fire resistant ledged door

Info

Publication number: GB2347712A
Application number: GB0013947A
Authority: GB
Inventors: Walter Ernest Inder; Alan John Smith; Kathleen Sandra Raymond
Original assignee: ROOKSMOOR TIMBER Co LIMIT
Current assignee: ROOKSMOOR TIMBER Co LIMIT
Priority date: 1999-07-10
Filing date: 2000-06-09
Publication date: 2000-09-13
Anticipated expiration: 2020-06-09
Also published as: GB0013947D0; GB9916148D0; GB2347712B

Abstract

A fire resistant door is formed from two wooden layers [1,2], each layer consisting of a number of planks [3] linked together by tongue and groove joins [4]. The two layers [1,2] are fixed together with fixing members [6] and have their respective tongue and groove joins [4] offset from each other. Ledges [8], located across the planks [3] on one side of the door, are secured in place using further fixing members [9], which are recessed into the ledges [8]. The ledges [8] cover the heads of the fixing members [6] used to hold the layers [1,2] together, and strips or caps are secured over the heads of the recessed ledge fixing members [9]. A layer of intumescent material may be sandwiched between the layers [1,2] of the door. A strip [13] of intumescent material may be provided around the edge walls of the door or frame [14]. The heads of the ledge fixing members [9] may be aligned along a groove in the ledge [8], which is then filled by gluing and pinning a wooden bead [11] into position.

Description

"Improvements Relating To Fire Doors" Conventional fire doors are made from fire resistant material or specially treated or coated timber. It is difficult to make these doors particularly attractive or to make them to appear like an old fashioned timber door, particularly those made from inter-connected planks. The invention has as its object the creation of an attractive door which will nevertheless be capable of meeting specified safety standards for fire resistance.

According to the invention there is provided a fire door construction comprising two wooden layers, each layer comprising an array of planks linked together by tongue and groove joints, such that the joins between the planks on one side of the door are off-set from the joins between the planks on the other side of the door to define overlap regions at least equal in distance to the plank thickness, the planks in the two layers being secured together by positive fixing members, at least in said regions of overlap, ledges located across the arrays of planks on one side of the door to cover the heads of the fixing members and secured in place by further positive fixing members whose heads are recessed into the ledges, and covering strips or caps secured into the recesses over the heads of the further fixing members.

With such a construction the planks are held together very securely by the various fixing members and the overlap between the joins in the two layers of planks ensures that there is no direct route for flames to pass from one side of the door to the other. For even further security there will preferably be a layer of intumescent material sandwiched between the two layers of planks of the door. Thus, when subjected to heat, the intumescent material will expand in the region between the planks to provide further resistance to the passage of fire through the door. Ideally a layer of intumescent material will also be provided around the edge walls of the door or frame so that, when the door is set into the frame, the intumescent material will expand into the gap between the door and the door frame.

The positive fixing members will be of the type which can be driven into the two layers of planks and will have ribbed features which resist the removal of the fixing members, so that the two layers of planks are held securely together. Screws will be the particularly preferred type of fixing member but ribbed nails or the like are another possibility.

In the preferred arrangement the heads of the further fixing members will be aligned along a groove in the respective ledge, that groove being filled by a wooden bead.

In any event the strips or caps which are secured into the recesses over the further fixing members will ideally be held in place by gluing and pinning. The further fixing members will ideally extend into both layers of the planks of the door.

The invention may be performed in various ways and a preferred embodiment will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a view of the rear face of a fire door constructed in accordance with this invention; Figure 2 is a horizontal section on the line X-X of Figure 1; and Figure 3 is an illustration of a detail of a hinge mounting for the door of Figure 1.

The door as shown in Figures 1 and 2 is formed from two layers 1,2 of planks 3. The planks in each layer are inter-connected by tongue and groove joints 4 and a decorative beading effect 5 is created at the join region. As can be seen from Figure 2 the joints 4 in the layer 1 are off-set from the joints 4 in the layer 2 so there is no direct path through these joints from one side of the door to the other. The planks are fixed together by a first set of screws 6 which, in particular, are secured through the two layers of planks in the regions of overlap 7.

The planks are further held together by ledges 8 on one side of the door. These improve the integrity of the door should it be subjected to the effects of a fire. Furthermore they cover over the heads of the screws 6 so that they are protected from any fire. The ledges 8 are themselves held in place by screws 9 which are set into a groove 10.

The heads of the screws 9 are then covered by a bead 11 which is glued and pinned into the groove 10.

It will be seen that this structure has substantial integrity both in terms of normal usage and in being able to resist the effects of a fire, to the extent which can be achieved with a conventional domestic fire door. Firstl) the potential passageway through the door for smoke anc flame is very limited due to the extent of overlap betweei the joints 4 in the front and rear layers 1 and 2 of the door planks. Furthermore it is very easy to insert a sheet of intumescent material into the region 12 between the twc layers of planks 1 and 2. When subjected to heat this wil- expand to block any gap between the two layers 1 and 2. The heads of the screws 6 and 9 are protected by the ledge 8 anc the bead 11 and the ledge and bead hide away the constructional features of the door and thus increase its attractiveness. The door could be supplied with a layer oi intumescent material set around the edge walls of the door, or an intumescent strip 13 could be set into the frame 1' for the door. At the hinge region, as shown in Figure 3, ai intumescent sheet 15 can be inserted between the hinge 1 ( and the layer 2 of the door.

Claims

1. A fire door construction comprising two wooden layers, each layer comprising an array of planks linked together by tongue and groove joints such that the joins between the planks on one side of the door are offset from the joins between the planks on the other side of the door to define overlap regions at least equal in distance to the plank thickness, the planks in the two layers being sealed together by positive fixing members, at least in said regions of overlap, ledges located across the arrays of planks, on one side of the door to cover the heads of the fixing members and secured in place by further positive fixing member whose heads are recessed into the ledges, and covering strips or caps secured into the recesses over the heads of the further fixing members.

2. A fire door according to Claim 1, wherein the heads of the further fixing members are aligned along a groove in the respective ledge, which groove is filled by a wooden bead.

3. A fire door according to Claim 1 or Claim 2, wherein the strips on the caps are secured into the recesses over the further fixing members by gluing and pinning.

4. A fire door according to any one of Claims 1 to 3, wherein the further fixing members extend into both layers of planks of the door.

5. A fire door according to Claims 1 to 4, wherein a layer of intumescent material is sandwiched between the two layers of planks of the door.

6. A fire door according to Claims 1 to 5, wherein a layer of intumescent material is provided around the edge walls of the door.

7. A fire door substantially as herein described with reference to the accompanying drawings.