GB2591134A

GB2591134A - Door seal

Info

Publication number: GB2591134A
Application number: GB2000740.7A
Authority: GB
Inventors: Michael Jones Jeffrey; Nicholas Purdom Hans
Original assignee: Linear Building Innovations Ltd
Current assignee: Linear Building Innovations Ltd
Priority date: 2020-01-17
Filing date: 2020-01-17
Publication date: 2021-07-21
Anticipated expiration: 2040-01-17
Also published as: GB202000740D0; GB2591134B

Abstract

A frame assembly 14 comprises a frame forming a closing area for a fire door 10, the frame assembly comprising a pre-applied intumescent strip 18 applied to an outer face of the frame such that it will be located between the frame and a wall when installed. The assembly may comprise two frame uprights 44 and a lintel and a common singular intumescent strip may be applied across all three members. The assembly may include a sill or threshold 26 which is also provided with an intumescent strip. The intumescent strip may be made of a graphite, hydrated sodium silicate, or monoammonium sulphate, based compound. Also disclosed is a method of enabling pre-certification in respect of fireproofing standards, a method of using the frame assembly whereby upon installation the gap between the strip and the wall is no wider than the rated expansion distance of the strip, and a doorset or door assembly comprising a frame assembly as described and a fire door.

Description

DOOR SEAL

The present invention relates to a door seal assembly, in particular for riser doors, for assisting with fire and smoke resistance in a building.

One of the functions of a door and door frame in a building is to slow down fire and smoke from spreading throughout buildings. Such doors can be specifically designed for this purpose -so called fire doors. Fire doors slow the spread of fire and also provide a means for closing the route of escape behind a user to maintain or enforce that protection.

There are different categories of fire doors, which can receive fire resistance duration ratings, such as FD30 for a 30 minute door or FD60 for a 60 minute door in the United Kingdom. The ratings given depend on their effectiveness at resisting a flame, fire or smoke, which is typically a duration of time, although other forms of rating can also be applied.

Typically fire doors are assessed through standardised test procedures, such as those defined by British Standards, e.g. BS476 part 22. Other Standards exist too. One such alternative standard is under EN16034. For example, a 30 min door would be E30 or E30Sa under this alternative Standard, the latter being where it is also rated for smoke at ambient temperature.

Tests may also be completed on a doorset, which additionally include the frame, plus seals. A doorset can thus be certified as well as the doors themselves separate to the rest of the doorset.

According to European Standard EN16034, the term doorset encompasses "pedestrian doorset, industrial, commercial and/or garage doorset, rolling shutter and/or operable fabric curtains including any frame or guide, door leaf or leaves, rolling or folding curtain, etc., which is provided to give a fire resisting and/or smoke control capability when used for the closing of permanent openings in fire resisting separating elements, including any side panel(s), vision panel(s), flush over panel(s), transom panel(s) and/or glazing together with the building hardware and any seals (whether provided for the purpose of fire resistance or smoke control) which form the assembly and fulfilling the provisions of this European Standard". The term doorset is thus commonly considered to be where the the frame and door are supplied together with all essential items involved in the final installed arrangement, and all typically provided by the one supplier in a kit.

The present invention is relevant to such doorsets, but also to door assemblies more generally, particularly where one or more of the essential items are supplied by more than one company -i.e. not all by the one company. Such a door assembly, which can likewise be tested and rated, might be just the frame, door and hinges, plus seals, in a kit, some or all of which might be made or packaged by the same or different companies, or the door, frame and hinges and seals, plus all the remaining door hardware, in the kit, either all made or packaged by one company or by more than one company.

Intumescent door seals are commonly used in doorsets and door assemblies. Such door seals are designed to swell when heated above a trigger temperature. Different materials can offer different intumescent properties, as is well known in the art, such as swell rate, trigger points, and fire resistance timings.

Such door seals will generally be fitted to the stiles and head of the frame of a fire-resisting doorset or door assembly, or into the door itself. The intumescent seals are commonly fitted into grooves that are cut into the door edge or door-edge facing surface of the frame, although sometimes they are on the face of a door stop that faces front (or back) edges of the door. In other arrangements they may be surface mounted, but they will typically bridge between the frame (or stop) and the door to create a flame or smoke barrier -to attempt to resist or stop flame, smoke or heat transfer through any gap between the door and the frame.

As indicated above, the useful characteristic of these intumescent door seals is that when an ambient temperature rises, e.g. due to a fire, the seal can swell to seal the gap between the door and the frame. This can prevent smoke transmission and will help to delay the spread of fire.

Due to the great danger that smoke poses to life and property, passive smoke seals might also be fitted, which provide a more permanent seal or barrier across the gap -to prevent smoke from travelling around the door edges prior to heating and swelling of the seals. These are often put at the bottom of the door as well as the sides and top thereof. They generally provide the seal when the door is in normal use -i.e. when closed, and at ambient temperatures. Many of these, however, will fail when exposed to fire conditions as they may melt or otherwise be destroyed by the heat. The intumescent seals, however, should by then trigger to replace them. Such passive seals when fitted within a door or door frame, for enabling a smoke rating to be achieved, are thus more typically for cold smoke or smoke at ambient temperature ratings.

Many door seals comprise both intumescent and passive elements in one seal, with the passive element being derived from the initial shape of the seal, and the intumescence component allowing that seal to swell upon exposure to heat to increase its effectiveness as a fire/smoke seal.

Some smoke seals comprise brushes or plastic blades to passively resist or stop the spread of smoke.

The skilled person will also realise that intumescent materials may act in different ways.

Some expand in all directions but may not provide much support to structural distortion of a door leaf. Others may expand primarily in one direction and provide some structural support to the door leaf. Some react in all directions.

In addition to the gap between the frame and the door, fire sealing can also be required between a doorset or door assembly (i.e. the frame part thereof) and a wall -to bridge any gaps through there, which gaps could otherwise compromise the effectiveness of the doorset or door assembly as a fire resisting barrier. Depending upon how the frame is installed, this can be a difficult task as backfilling of the gap between the frame and the wall may be necessary depending on the size of the gap.

For example, a back-filling material such as mineral wool might need to be used to fill the gap after installation of the doorset or door assembly, together with an unbroken capping or seal strip of mastic applied around the perimeter.

In new builds, or refits, particularly in commercial installations, these installations can be required to conform to official Standards so the backfill materials and the mastic would need inspection, which adds to the complexity of the fit. For example, the mastic would need to be shown to be an intumescent mastic, which is difficult to achieve after its application. Further, the back-fill would become unseen after installation so it could need inspection prior to fitment.

Without such checks a certification that these installations will adequately protect against the spread of smoke and fire can be difficult or impossible to provide, even where the doorset or door assembly itself is certified. Before the fitting process is undertaken, therefore, all products that are to be used may need to be checked for certification purposes, and the installer may need specific qualifications to allow him to certify his work, or otherwise assist the building inspector in providing the necessary signoffs for the build.

Further issues that can arise include the fact that intumescent mastic can be difficult to apply properly, whereupon even if it looks externally correct, it might not always provide a proper seal behind that external surface.

Another issue is that packers are commonly used during the installation of the frame to hold the frame in the correct position during its attachment to the wall. These packers -typically being thin wedges of plastic, can also interfere with the application of the mastic unless they are trimmed back to an acceptable depth behind the edge of the frame to enable them to be adequately covered by the intumescent mastic.

The present invention therefore seeks to offer an alternative design of doorset or door assembly and a new approach for certification of doorsets or door assemblies, and to make post-fitment certification of a build easier, thus reducing the difficulties associated with certification of any required backfill or the application of mastic as an intumescent strip around the frame during the fitting of a doorset or door assembly in a wall.

Furthermore, the present invention seeks to assist with the correct certification of the doorset or door assembly upon its installation to assist a building inspector or the like in certifying the installation in respect of fire or smoke resistance.

Statement of Invention

According to the present invention there is provided a frame assembly for a doorset or door assembly comprising at least a frame forming a closing area for a fire door, the frame assembly comprising a pre-applied intumescent strip applied to an outer face of the frame such that it will be located between the frame and a wall when installed in an opening in the wall.

More than one intumescent strip might be applied to the outer face of the frame. They may extend parallel to one another, and they may be spaced apart laterally with respect to their extending lengths.

Preferably the or each strip forms a continuous length along the component of the frame assembly to which it is applied, such as a frame upright or frame head or lintel.

The continuous length, however might be formed from more than one length of strip -which are ideally butted up against one another at their adjacent ends.

By virtue of the intumescent strip being pre-applied, the frame assembly together with its intumescent strip can be pre-certified, i.e. certified prior to its installation, and beneficially pre-certified at the time of purchase from a hardware store.

The present invention also provides a method of enabling pre-certification of a frame installation comprising providing a frame component and pre-applying an intumescent strip to an in-use outer face of the frame component such that the intumescent strip will be located between the frame and a wall when installed in an opening in the wall.

Preferably the invention comprises providing two frame uprights and a frame head or lintel, all three of these frame components each comprising at least one pre-applied intumescent strip -applied to an outer face of the frame component such that the or each intumescent strip will be located between the frame and a wall when the three components are installed in an opening in the wall.

There may be one continuous strip around the three components or three separate but preferably abutting intumescent strips, abutting end to end -e.g. at the joints between the components of the frame.

Preferably the frame assembly is formed from the three frame components. However, the frame assembly may additionally comprise a sill or threshold. Preferably the sill or threshold is also provided with a pre-applied intumescent strip on its in-use underside surface. Typically this additional pre-applied intumescent strip is a separate strip to those or that of the frame uprights and head or lintel as commonly the bottom ends of the uprights do not meet the sill at the ends of the sill or threshold. Instead the ends of the sill or threshold may extend laterally outward relative thereto. However, in a doorset or door assembly with a premeasured sill or threshold, the ends may meet and thus a continuous intumescent seal may extend around all four side of the doorset or door assembly -i.e. under and around the sides of the sill or threshold as well as up and over the uprights and head of the frame assembly.

The pre-application of the intumescent strips, as provided by the present invention, offers an added benefit of reducing costs associated with labour during the fitting process as there is no need to undertake the process of the application and inspection of an intumescent mastic, or the trimming of the packers backward of the edge of the frame for permitting an adequate depth of that mastic to be fitted. It will also avoid the need for a post-fit check and certification of the materials used as the pre-applied strip can be pre-certified, and when pre-applied before purchase of the frame components, the certification can be pre-applied prior to purchase of the frame components.

In some embodiments the intumescent strip is made of a graphite compound. Such compounds are commonly chosen for intumescent strips as they offer fire resistance and they are able to conform to various shapes.

In some embodiments the shape chosen for the strip -to fit to the outside of a frame -which commonly has a flat planar external surface, is a rectangular shape. At the time of installation, the rectangle can be generally flat against the flat planar external surface. The ends of the rectangle may be square, although in other embodiments the shape is just relatively flat, with the shape of the ends of the flat shape being any chosen form.

The outside of the frame can have a groove into which the strip is installed, much like that commonly found in door edges. In preferred frames, however, the frame has a flat surface for receiving the strip.

Preferably the frame is formed of a metal, such as steel or aluminium. A preferred type of frame component is one formed from a folded steel sheet. Extruded aluminium frame components are also suitable for use with the invention, as are composite frame components.

Frames made of plastic are generally not suitable as they tend to melt when exposed to the level of heat needed to activate the intumescent strip. Preferably, therefore, the present invention does not include plastic frame components for the upright and head components of the frame assembly.

Most styles of fire door, however, are suitable for use in the present invention -for fitting in the frame to form the doorset or door assembly. Fire doors can be made of wood, plastic or metal, and may have a fire or heat resistant core, or an adequate thickness or some other known fire resisting property or characteristic.

In some embodiments the intumescent strip is made of a hydrated sodium silicate based compound. This, like graphite compounds, can be fire resistant and is able to conform to many shapes.

In some embodiments the intumescent strip is made of a monoammonium sulphate based compound. Again this can be fire resistant and able to conform to many different shapes.

In some embodiments, at the time of frame installation, or at the time of purchase of the frame component, the intumescent strip has thickness of between 0.5mm and 6mm from the back surface of the frame component (or from the surface of the frame component that faces or lies adjacent to the wall in the opening of the wall.

10 15 20 In some embodiments the intumescent strip has a width of between 10mm and 50mm, measured perpendicular to the length of the frame component and perpendicular to the thickness of the strip. This width is typically less wide than the surface of the frame component on which the strip is applied, fitted or adhered.

In some embodiments the frame comprises a folded form, e.g. from folded metal -preferably steel. In other embodiments it is an extrusion, such as an aluminium extrusion. Preferably it comprises a bead member along its length for defining guide for a plasterer.

The frame component may comprise bead with a perforated flange for receiving and better enabling adhesion of plaster.

Preferably the perforated flange provides a wall-return for the frame component, the perforated flange in use thus lying substantially parallel to the wall surface of a room, rather than in the opening of the wall.

Preferably the intumescent strip is not applied to the rear of that perforated flange. Preferably it instead is provided on a surface of the frame component that extends perpendicular to that perforated flange.

The intumescent strip may be combined with a passive smoke seal, such as a plastic blade or a brushes to additionally provide a passive seal against smoke ingress around the frame between the frame and the wall.

In some embodiments the frame assembly comprises a fire door as well as the frame.

In some embodiments the frame assembly is a pre-assembled doorset or door assembly with the door pre-installed in the frame.

In some embodiments the frame assembly is for use with a riser door. The frame assembly is thus then generally for fitting in the wall of a vertical riser of the building, such as a riser duct.

According to a further aspect of the present invention there is provided a method of using the frame assembly of the present invention, comprising fitting the frame component in the opening with the intumescent strip facing the wall of the opening, the space or gap, if any, between the strip and the wall facing it, being no wider than the rated expansion distance of the strip.

In some embodiments, the space or gap, if any, does not exceed 20mm, or falls within the range 0 to 50mm, or more preferably 0 to 20mm.

With this use, the intumescent strip will be able to expand to fill the gap between the frame and the wall during a fire in order to prevent or resist the fire or smoke on one side of the door from breaching across to the other side of the door.

In some embodiments, during the installation of the frame assembly, no intumescent mastic is applied to the frame assembly after the frame is located in the opening. This avoid problems involving the application of the mastic. A non-intumescent mastic can instead be used, which requires no certification due to the pre-installed strip offering the required certification.

The present invention also provides a doorset or door assembly comprising a frame assembly as defined above, wherein a door -preferably a fire door, is provided for fitting within the frame assembly.

Brief description of drawings

These and other features of the present invention will now be described in further detail, purely by way of example, with reference to the accompanying drawings in which: Figure 1 shows a frame assembly in the form of a doorset or door assembly for a riser, with intumescent strips on both sides and the top and bottom frame components. Figure 2 shows a vertical section A-A through the doorset or door assembly of Figure 1.

Figure 3 shows an enlargement of a top part or sub-assembly of the doorset or door assembly of Figure 2.

Figure 4 shows an enlargement of a bottom part or sub-assembly of the doorset or door assembly of figure 2.

Figure 5 shows part of the top subassembly from Figure 3, showing a section through a top frame component and intumescent strip.

Figure 6 shows part of the bottom subassembly from Figure 4, showing a section through a bottom frame component and intumescent strip.

Figure 7 shows a horizontal section through the doorset or door assembly of figure 1.

Figure 8 shows an enlargement of a hinge side part or sub-assembly of the doorset or door assembly of figure 7.

Figure 9 shows an enlargement of a lock side part or sub-assembly of the doorset or door assembly of figure 7.

Figure 10 is a perspective view of a doorset or door assembly with a partial view of a wallboard surrounding it.

Figure 11 is a rear elevation of the doorset or door assembly of Figure 10.

Figure 12 is a vertical section through the doorset or door assembly of Figure 11. Figure 13 is a side elevation of the doorset or door assembly of Figure 10.

Figure 14 is a front elevation of the doorset or door assembly of Figure 10.

Figure 15 is an enlargement of a corner of the wallboard from Figure 10. Figures 16 and 17 show variants of the frame components in figures 5 and 6.

Detailed description of drawings

Referring first of all to Figure 1, there is shown a doorset (or door assembly) 12 for a riser, the doorset or door assembly 12 providing a frame assembly (or frame) 14 with top, bottom and side frame components and a hinge-line near a left (as shown) side frame 48. The illustrated doorset or door assembly 12 of this embodiment includes a door 10 with a three point lock 16 to allow the door to be latched closed relative to the frame assembly 14. Other forms of door latch or door lock can instead be used with the present invention.

The door 10 fits inside the frame assembly 14, and is surrounded on all four sides by the frame components and in this embodiment it is fixed in place, when closed and latched, by the three point lock 16.

In other embodiments, the three point lock 16 may be replaced with a single point lock or other known latch/lock systems. Further, in some embodiments, the frame assembly might not include a bottom frame component, as it might be for fitting above an existing threshold.

The frame assembly 14 in this embodiment is thus formed by a plurality of identifiably separate frame components 48, 50, 52 (herein four) and they may be formed separately and then bolted, welded or otherwise joined together. In this embodiment the frame components are made of folded metal -preferably steel -sheets or plates, but they can instead be extruded sections or fabricated/cut sections.

As shown in Figures 5 and 6, the frame components can have different forms relative to one another. For example, as shown the section of the base or threshold frame component 30 as shown in Figure 6 can be different to the section for the frame components used for the side frame components and top or head frame components as shown in Figure 5.

With the section shown in Figure 5, which is an advantageous sectional design for the side and top frame components, there is a projecting bead 54. This, when the three similarly sectioned frame components are in their combined form (i.e. around the door and in the wall) provides a sidewardly extending feature relative to the frame section as shown in Figure 5, but in use this will be a forwardly protruding corner ridge 54 relative to a central plane of the door 10. This ridge 54 will extend around the side and top perimeter of the door to provide a guide for a plasterer that corresponds to the level to which plaster will be applied over sides 62 of the frame components14 during the installation of the doorset or door assembly 12.

In this preferred embodiment the ridge 54 sits flush with the adjacent face of the door 10 to achieve a more hidden appearance for the fitted door. In other words, while the door 10 of this embodiment has a flat front surface 60, when that door is closed the front surface 60 of the door 10 is substantially co-planar with the front-most plane 56 defined by the tip of the ridges 54 of the three frame components around the sides and top of the door 10. This is beneficial where the door is a riser door, as riser doors tend to want to be less prominent in a room or corridor than a more frequently used everyday access door. It can also be desirable for minimalist interior designs.

The frame 14 is rectangular in this embodiment as the door 10 is likewise rectangular -they will generally be shaped to fit with one another.

The frame component 14 shown in Figure 5 comprises a four-times-folded metal sheet, thus defining five generally planar plates, with at least one of the folds forming the corner ridge 54. Two of the sectional components with this section are longer than the third, and define side components 48, 50, and the third defines a top frame component 52.

The front-most plane 56 is extended frontwards (relative to the central plane of the closed door 10) of a plaster-receiving flange 62 of these frame components 14, the plaster-receiving flange 62 being perforated, or otherwise roughened, to facilitate the fixing of plaster thereto during installation of the frame components 14 within an opening in a wall. With perforations the frame component can also be more easily attached to the wall -e.g. with nails or screws.

These frame components are made of a metal such as steel or aluminium.

In some applications the frame components may be painted or galvanised, or both.

The door 10 may also be made of a folded metal sheet, or some other known door form may be used.

For a fire door, the door will typically be infilled with, or made from, a fire or heat resistant or insulating material 40.

Figure 2 shows a vertical cross section through the doorset or door assembly 12 of Figure 1. At a top of the doorset or door assembly 12, there is provided a top sub-assembly 20, which is shown in greater detail in Figure 3. At a bottom of the doorset or door assembly 12, there is provided a bottom sub-assembly 22, which is shown in greater detail in Figure 4.

Figure 3 shows an enlargement of the top sub-assembly 20 of the doorset or door assembly 12 of Figure 2. The top sub-assembly 20 comprises the top sectional component 52 of the frame component 14, plus also a sprung pivot pin 24, an intumescent strip 18, an upper portion of the door 10 and a conventional door seal 28. The intumescent strip 18 is attached to an outside face of the sectional component 52. The spring pivot 24 fixes the door 10 to the frame component 14, allowing the door 10 to rotate about the spring pivot pin 24 to open.

The intumescent strip 18 is provided to each of the frame components that form the sides and top of the frame assembly, around the outside face of the frame components to form an intumescent barrier around the frame between the frame and the wall.

Figure 4 shows an enlargement of the bottom sub-assembly 22 of the doorset or door assembly 12. The bottom sub-assembly 22 comprises a threshold frame component 46, also having an intumescent strip 18, plus also a bottom pivot pin 26 (this time a fixed one), plus a convention door seal 28. Also shown is a bottom portion of the door 10. The intumescent strip 18 is again attached to an outside face of the threshold frame component 46, and in this embodiment, as the ends of the threshold frame component are attached to the bottoms of the side frame components 48, 50-in a manner to form a ring around the door such that the outside faces of the four attached frame components also define a ring, the four intumescent strips 18 all together form a barrier for fire/smoke during use, which barrier is a full ring around the opening.

The bottom pivot 26 is a fixed pivot in this embodiment as only one of the pivot pins needs to be sprung to allow insertion and easy removal of the door from the frame the The second pin 26, co-operates with the sprung pin 24 to allow the door 10 to rotate open and closed within the opening defined by the four frame components.

As seen in Figures 3 and 4, the sprung pivot 24 comprises a top part 72 positioned in a cylinder 78 within the door and is arranged to slide therein contrary to a biasing force provided by a spring 80 such that a free end of the top part engages into a correspondingly positioned hole in the top frame component.

The bottom pivot pin 26 comprises a bottom pin 74 in the bottom sectional component 46 and it fits in a correspondingly positioned bottom hole 76 in the door 12.

These thus define pivots that are used for pivotal mounting of the door within the frame 14 using the suitably positioned pins 70, 74 and holes 72, 76 in the relevant areas of the frame components and door.

The top movable pin 70 in the door 10 is moveable to facilitate easy removal of the door 10.

Rather than top and bottoms of the door, the pins may be in sides of the door to allow pivotal movement of the door around a rotated axis.

As can be seen in Figures 3, 4, 5, 6, 8 and 9, there is a seal 28 extending around the perimeter of the inside face of the frame 34. The seal 28 is for engaging against the door 10 when the door 10 is closed within the frame 14. This seal 28 can also be made from an intumescent material to enable that part also to be certified for fire resistance.

Referring to Figures 4 and 6, the bottom sectional component 46 of the frame 14 has a step 64 to allow the bottom sectional component 46 to act as a door stop. The other three sectional components 48, 50, 52 have flat inside faces 34, allowing the door 10 to open and close freely upon rotation. The step 64 can support the hinged end of the door -e.g. during installation or if the hinge fails.

In the embodiment of Figure 5, the extended flange 62, a flat inside surface 66, the stepped inside surface 82 and a further extended flange 68 of the two side sectional components 48, 50 together define an approximate U section for this frame component, in section. This U shape can have a width to roughly match a wall thickness as this forms the frame within the wall.

The top sectional component 52 is similar but shorter in length than the two side frame components as the final frame 14 of this embodiment is for an upright rectangular door.

The further extended flange 68 and the perforated flange 62 offer stiffness and rigidity to the frame 14 The bottom sectional component 46 has a different folded form in this embodiment. As shown in Figure 6, it has a folded inside face 34 to provide a step to act as a door stop. As it is for a threshold, however, it will generally sit flush or close to flush with the floor of the room. As such it needn't have a flange for plaster.

To maintain stiffness, the section can have 5 folds as shown, to thus form 6 planar faces. There is a bottom planar face 84 to which the intumescent strip 18 is applied, a door edge facing face 86, the step that provides a stop defining face 88, the folded inside face 34 and two adjacent end faces 90, 92, which can be welded together to make it additionally stiff. This part of the frame 14, by also being metal, is also thus substantially rigid once all folded and welded together into a ring or loop, thus being suitable for use as a threshold.

Figure 7 shows a horizontal cross section through the doorset or door assembly 12 of Figure 1. From it, Figures 8 and 9 show greater details of the ends of the section.

Figure 8 thus shows an enlargement of the hinge side sub-assembly 36 of the doorset or door assembly 12 of Figure 7. The hinge side subassembly comprises the door 10, the sectional component 48 (side) of the frame 14, the intumescent strip 18, a dog bolt 42 and the conventional seal 28. The dog bolt 42 is provided in the frame to fit into corresponding holes within the door 12 when the door 10 is closed. The dog bolt can add strength or security to the door when closed. In particular, however, it is provided to resist warping of the door or frame out of their corresponding planes as they heat up, thus preventing gaps from forming that would bypass the seals between the door and frame.

As discussed previously, the intumescent strip 18 is provided on the outside of the frame component to face the wall.

Referring next to Figures 16 and 17, a variant to the frame components of Figures 5 and 6 are shown. In this variant, instead of a single intumescent strip, a pair of intumescent strips are provided. As shown these are spaced apart. This can be formed also from a single strip by cutting out a middle part, but that is likely impractical on cost grounds.

Depending upon the shape, size or form of the frame component, more than two strips might be helpful in ensuring a full or proper barrier between the frame and the wall.

Referring next to Figure 9, this instead shows an enlargement of the lock side of the doorset or door assembly 12 of Figure 7. The lock side sub-assembly 38 comprises the door 10 with a mineral wool core 40 -e.g. Rockwool, another sectional component (side) 50 of the frame 14, the intumescent strip 18, the three point lock 16 and the conventional seal 28. The three point lock 16 is shown to have an engagement member 94 for engaging into a hole in the frame component -in this instance in the part numbered 34.

The intumescent strip 18 is again provided on the outside of the frame component.

As discussed above, the door 10 can be formed from one or more folded metal sheets, forming a hollow interior, which is filled with the insulating material 40, as can be seen in Figures 3, 4, 8, 9 and 12.

The door thus assembled will have a cavity inside it, infilled with the insulating material 40, such as Rockwool, as seen in Figure 9.

As seen in Figures 10, 11 and 14, an example of fitment of the frame assembly in a wall is shown. In this example, wallboard forms the walls into which there is an opening for the frame assembly.

Figure 10 shows a rear view of a breakaway part of a section of wallboard with a wall face forming wallboard having an upright 44 and a lengthwise part 45. These may be parts of bigger sheets. Extending around the opening for the door are further wallboard lengths 47, 49, two of which are shown. Extending these boards across the top of the opening (board 49) and to the sides of the opening (part shown as board 47) the opening for the frame assembly is defined.

As seen in Figure 11, the frame assembly thus fits in the opening thus defined with the perforated flanges 62 lying against the wallboards. Plaster is then applied to the front face of the perforated flanges 62 and the wallboards 44, 45 to a level of the front-most plane 56 as defined by the features 54.

The present invention relates to the frame assembly, or the doorset or door assembly comprising that frame assembly. The invention also relates to methods of installing the frame assembly or doorset or door assembly, the method comprising providing a frame assembly or doorset or door assembly as described above and fitting it in an opening in a wall.

Preferably the installation involves plastering over a flange of the frame assembly up to a front-most plane of the frame assembly.

The above embodiments are only examples and are not intended to limit the scope of the invention as claimed. The present invention is thus defined above purely by way of example and modifications to the invention may be made within the scope of the claims appended hereto.

Claims

CLAIMS: 1. A frame assembly for a doorset or door assembly comprising at least a frame forming a closing area for a fire door, the frame assembly comprising a pre-applied intumescent strip applied to an outer face of the frame such that it will be located between the frame and a wall when installed in an opening in the wall.
2. The frame assembly of claim 1, having a pre-certification in respect of fireproofness in respect of fireproof Standards prior to its installation.
3. The frame assembly of claim 1 or claim 2, comprising two frame uprights and a frame head or lintel, all three of these frame components each comprising at least one pre-applied intumescent strip applied to an outer face of the frame component.
4. The frame assembly of claim 3, wherein the three intumescent strips are a common singular strip applied around the frame assembly
5. The frame assembly of any preceding claim, further comprising a sill or threshold.
6. The frame assembly of claim 5, wherein the sill or threshold is also provided with a pre-applied intumescent strip on its in-use underside surface.
7. The frame assembly of claim 6, wherein the additional pre-applied intumescent strip is a separate strip to those or that of the frame uprights and head or lintel of the frame assembly.
8. The frame assembly of any preceding claim, wherein the intumescent strip is made of a graphite compound.
9. The frame assembly of any preceding claim, wherein the intumescent strip or strips are a flat or rectangular shape.
10. The frame assembly of any preceding claim, wherein at least one of the frame components is a metal frame section.
11. The frame assembly of any preceding claim, wherein the frame has a flat surface for receiving the strip.
12. The frame assembly of any preceding claim, wherein the intumescent strip is made of a hydrated sodium silicate based compound.
13. The frame assembly of any preceding claim, wherein the intumescent strip is made of a monoammonium sulphate based compound
14. The frame assembly of any preceding claim, wherein at the time of purchase of the frame component, the intumescent strip has thickness of between 0.5mm and 6mm.
15. The frame assembly of any preceding claim, wherein the intumescent strip has a width of between 10mm and 50mm, measured perpendicular to the length of the frame component and perpendicular to the thickness of the strip.
16. The frame assembly of any preceding claim, wherein a door is fitted within the frame.
17. The frame assembly of any preceding claim, wherein the frame assembly is a pre-assembled doorset or door assembly with a fire door pre-installed in the frame.
18. A method of enabling pre-certification of a frame installation comprising providing a frame component and pre-applying an intumescent strip to an in-use outer face of the frame component such that the intumescent strip will be located between the frame and a wall when installed in an opening in the wall.
19. The method of claim 18, comprising providing a frame assembly in accordance with any one of claims 1 to 17, wherein the frame component of claim 18 is part of the frame assembly.
20. A method of using the frame assembly of any one of claim 1 to 17, comprising fitting the frame component in the opening with the intumescent strip facing the wall of the opening, the space or gap, if any, between the strip and the wall facing it, being no wider than a rated expansion distance of the intumescent strip.
21. The method of claim 20, wherein during installation of the frame assembly, no intumescent mastic is applied to the frame assembly after the frame is located in the opening.
22. A doorset comprising a frame assembly as defined in any one of claims 1 to 17 and a fire door.
23. A door assembly comprising a frame assembly as defined in any one of claims 1 to 17 and a fire door.