This invention to joist hangers, more particularly, but not exclusively, of the type that in use are attached to a wall or other vertical structure and which are adapted to receive and support a joist during the building or repair of a floor or other structure that is to be supported by the joist.
Wooden joists are conventionally spaced apart and prevented from relative displacement about their longitudinal axes by cross members known variously as a noggins or dwangs (hereinafter jointly referred to as noggins).
Noggins are usually in the form of short lengths of timber, often off-cuts, which have their ends nailed respectively to the adjacent vertical faces of a pair of timber joists. Each noggin usually has its ends angled in opposite directions so that an upper end will bear against an upper portion of one joist whilst the opposite end will bear against a lower portion of the adjacent joist. Noggins are usually fitted in pairs so that one noggin is inclined in the opposite direction to the other noggin. A pair of joists typically is provided with a series of noggins along their lengths to retain the desired spacing whilst inhibiting any relative rotational movement - that is relative rotation about their respective longitudinal axes.
As each noggin is usually cut individually from wooden off-cuts, their fitting to the joists is often poor and their function is frequently unsatisfactory. Once a series of joists has been covered by floor boards, or the like, it is impossible to assess the efficiency of the various noggins without lifting at least part of the floor. The adequacy of noggins is further compromised by a reduction in the quality of building timber compared with that used 30 or 40 years ago. Modern building timber is usually kiln dried, has a greater number of wood knots, and can easily twist or otherwise deform, particularly where central heating is used.
Noggins are notorious for impeding the subsequent insertion of electrical and plumbing services which need to be laid along the joists and to pass through apertures that need to be drilled horizontally through one or more joists. Indeed the drilling of such apertures can be difficult if a noggin has been placed in an inconvenient position, and the proximity of the adjacent joist prevents the formation of a horizontal aperture. Where apertures are required through a series of adjacent joists, one is left with a series of inclined apertures and the problem of drilling these in alignment.
An example of a joist hanger, referred to as a structural connector, is described in US Patent Application
Another example of a joist hanger, referred to as a perimeter clip for tying an end of a beam (in a dropped ceiling) to an angle of a moulding, is described in US Patent
US Patent Application
According to a first aspect of the invention there is provided a joist hanger comprising: a rigid support defined by an elongate sheet which is folded and arranged in the form of a prismatic box structure with an abutment plate which in use abuts a vertical surface; characterised in that a plurality of joist supports are formed integrally with the rigid support each being able to receive a joist.
In one preferred embodiment the joist hanger is hung or suspended from a vertical surface, such as a course of bricks, by way of a wall hanger. The wall hanger includes a horizontal strap or brace, which may be in the form of a flat portion, formed integrally with the joist hanger and optionally extending along substantially the entire length of the rigid support. Where the rigid support is a flat elongate plate, when it is folded into an L-shaped, or S-shaped form, the wall hanger is defined by a flattened face.
In one embodiment the joist supports are adapted to slide laterally along the rigid support. In an alternative embodiment the joist supports are formed integrally with the rigid support.
It is seen therefore that use of the invention, where the joist supports are formed integrally with the rigid support, facilitates rapid and precise installation of joists, for example for flooring, as carpenters no longer need to measure gaps between joist, mark and fix individual joist hangers, as these are already in place.
The rigid support may be in the form of an elongate plate, strut, extrusion, rod or the like.
Ideally the rigid support is in the form of an elongate plate, strut, extrusion, rod or the like, however as mentioned above it may be generally L-shaped, or S-shaped. In use the rigid support is placed against a wall and hung by way of a wall hanger on a course of bricks. Fixings to the wall can be made after further courses of bricks are laid on the wall hanger. The joist hangers are located on opposite walls of a room and joists are slung between opposite hangers.
Provided a joist hanger at one end is aligned to the corresponding end of the opposing hanger (and the corners of the room are 'square'), individual joist supports will face opposite one another, thereby speeding the process of installing the joists. A carpenter now only has to ensure that joists are cut to the correct lengths and properly located and fixed in individual supports and this task can be carried out by a less skilled assistant, thereby further reducing costs.
Joist supports are ideally defined integrally with the joist hanger, as hereinafter described, however individual, or groups of joist supports, may be fitted, connected with or joined to the abutment plate, by way of clips, mechanical fixings or welded joints.
The rigid support is ideally fabricated from a strong and stiff material, such as: synthetic plastics, steel, mild steel, aluminium or a metal alloy.
The rigid support is defined by an elongate sheet which is folded and arranged in a prismatic section. The prismatic section may be square, rectangular or triangular.
Most preferably the rigid support is triangular in cross section, including one corner which is a right angle, which corner, in use rests against a wall or other vertical surface or upright.
In the alternative embodiment of the rigid support being in the form of a prismatic section, cut-outs in portions of the prismatic section are adapted to define joist supports.
In another embodiment the locations for joist hangers may even be marked or pre-formed, by way of partially cut or pre-pressed apertures, for example in the prismatic section, ready for a carpenter to press out and define when using the joist hanger. It is seen therefore that use of the invention greatly reduces the time required to install supports and joists from which a raised floor is to be supported. This reduction in time it is felt reduces considerably the cost of building dwellings, offices and similar buildings.
In the aforementioned particularly preferred embodiment, wherein the support is triangular in cross section and includes one right angle corner, a portion of the side of the prismatic section, that in cross section defines the hypotenuse, may be removed so that a recess is revealed, said recess defines the joist hanger. The portion or portions removed may be folded back so as to defined webs or side panels, which may fold inwards or outwards so as to acts as guides for receiving the joists.
Furthermore with increasing demand on recycling of materials, as a result of demands on resources (such as wood and steel); as well as increasing legislation on renewable buildings, the fact that at the end of a life of a building, key components can be removed and reused, is felt to be a further unique feature of the joist hanger.
Individual joist supports may have lateral webs for strengthening. These webs may be welded or to the abutment plate.
Preferably the joist hanger includes a support mounting, which in use receives a panel or plaster board, defining a ceiling.
The support mounting is ideally a recess defined by a fillet or projection formed integrally with or supported by the joist hanger. The recess or fillet ideally extends laterally along a length of the joist hanger; preferably the recess or fillet extends along a length less than 10 cm, ideally it extends along a length less than 7 cm and most preferably it extends along a length of less than 5 cm.
The joist hanger and/or abutment plate optionally includes one or more apertures, such as holes or slots, through which fixing means, such as nails, screws or bolts or may pass in order to attach, fix or anchor the joist hanger to a wall, to bricks, blocks, girders or some other vertical surface or structure.
The joist hanger optionally includes a sheet of resiliently deformable material having one side adhered to a support face or load plate of the joist support and the opposite side of the sheet has an adhesive surface to adhere to a joist. An advantage of this arrangement is that the sheet of material acts as a pressure pad and behaves as a shock absorber between the plate and a joist, reducing the transmission of vibrations from one to the other.
The joist hanger is preferably formed as a pressed moulding from a suitably strong material, such as stainless steel; any other suitable steel alloy; a synthetic plastics material (having a high tensile strength) - the plastics material being formed, for example, by a casting or injection moulding process. Alternatively, the joist hanger may be formed as a casting.
In one embodiment of the invention, the joist hanger preferably includes a screw thread having its axis normal to the abutment plate. A boss, in which a thread is formed, may be defined in the abutment plate or the screw thread may be formed in an insert carried by the abutment plate in such a manner that the insert cannot rotate. Such insert can, for instance, have a square outer cross-section and be a sliding fit within a complementary aperture in the abutment plate or a boss secured to the abutment plate. A noggin preferably comprises a pair of these joist hangers having opposite hand screw threads which engage corresponding threads of a screw adjuster that is operable to brace the joist hangers between a pair of adjoining joists.
In a further embodiment of the invention, the joist hanger preferably has an opening formed through the abutment plate and/or in the joist support and/or the hanger, the opening being adapted to receive a pipe or an electrical cable or other service, such as a fibre optic or other cabling. In such an embodiment, the joist hanger preferably supports a tube socket positioned around the opening. The tube socket is preferably defined by a plug which fits into the opening, and the plug defines a passage for receiving services, such as pipes, cables or leads.
In other embodiments, whose advantages are described below, there are features which will become apparent when reading the description, in light of the drawings. For example, according to one embodiment, flaps or tabs are provided on the hanger in order to engage with a layer of cement or mortar.
In a yet further embodiment, where it may be desirable that openings of one plate are aligned with those of another, joist hangers are ideally arranged to be secured on opposite sides of a joist, wall, vertical structure or partition. One way of achieving this is to provide a joist mounting kit comprising: at least one pair of joist hangers, a template to fit over a joist to define an axis of a bore of an opening, for example to be drilled through the joist in alignment with the openings, whereby in use, a pair of joist hangers to be secured to opposite sides of the joist have their openings in registration with the hole in the joist. Alternatively two joist hangers may be connected, or adapted to be connected, one to another.
Further embodiments of the invention will now be described, with reference to the Figures, in which:
The joist hanger abutment plate 10 is preferably formed as a moulding integral with the support mounting boss 12 and the webs 13, 14, 15 and 16. The moulding can be, for instance, an injection moulding using a suitable plastics material such as polypropylene or a fibre reinforced thermoplastic material. Instead of being moulded, the joist abutment plate 10 can be cast from any suitable material, or be fabricated from sheet material. The joist abutment plate 10 is provided with attachment means in the form of four apertures 17, 18, 19 and 20 for receiving fixing means such as nails, screws or other fixings permitting a joist to be secured thereto.
Other forms of fixing means may be used, for instance staples driven through one or more of the webs 13, 14, 15 or 16, or an adhesive are described below.
A template is used to drill holes for guides, as described below. A groove is chased for the joist hanger to be retro-fitted or the hanger is laid onto a course of bricks. Once positioned 8mm or 10mm screws or Rawlbolt (Trade Mark) are fixed to connect the hanger to a wall so that it is tightened and lays flush against wood or a brick surface.
The sheet of material 21 is preferably a pressure pad formed of a spongy material so that it will act as a shock absorber between the joist abutment plate 10 and its joist. This pressure pad also serves to bed the joist abutment plate 10 securely over any irregularities, such as knots, in the abutting vertical surface of the joist. Optionally a sheet 21 a may be placed on an opposite side of a joist hanger to rest against a wall (not shown) or noggin 58.
It will be appreciated that the joist hanger optionally includes one or more apertures, such as holes or slots, through the abutment plate, through which fixing means, such as nails, screws or bolts or may pass in order to attach, fix or anchor the hanger to a wall, to bricks, blocks, girders or some other structure.
Referring to
Referring now to
The fact that the batons provide an elongate area into which a plasterboard or ceiling board can be nailed, presents a major time saving opportunity to builders and tradesmen as considerably less effort is needed in order to fit ceilings.
The hangers shown above are typically 2 to 5 cm in width with curled inward edges. The abutment plate, which in use abuts a wall, is suspended from a wall or course of bricks by way of a hanger with a horizontal strap/brace which can be 400 mm or 600 mm in length. A joist support which is attached to said abutment plate is typically flat but may have edges defied to receive specific thickness joists.
Joist supports can be of varying length. Straps or braces can be intermittently fixed for example by way of screws, bolts, glue or nails. An advantage of this is that the straps/braces act as guides for a first layer of plaster to be screeded in between fixers. This again provides a better finish and saves time.
Referring to
Advantages of the joist hanger are that floors can be laid quickly and can be assembled whilst brick work is being undertaken and then dropped into place on a line of joist hangers, thus internal platforms/scaffolding is no longer required and when laying onto supporting brickwork, work can be resumed to the next level whilst floors are boarded and services fitted. There is therefore a huge saving on labour and build time.
The joist hangers can be tailor made or sold off the shelf. Other examples of where the joist hangers can be used are as shed bases, foot bridges or raised walkways.
In addition to the above advantages it will be appreciated that as joist and walls are bolted one to another there is generally a stronger structure provided as a result of the bracing effect of fixings and timber being directly supported by and connected to brickwork, concrete, steel or other rigid fixings on material surfaces by way of them resting on the joist support and ceiling boards being integral therewith as a result of being inserted in the flange.
Referring to
It is apparent that with internal standalone brick foundations minimal pressure is placed on the existing internal walls and there is reduced work force necessary on-site, as a significant amount of joinery work can be completed off site.
A screw handle comprises a central handle fixed to oppositely handed threaded studs which screw into their respective ends. It will be seen that each support mounting comprises a mechanism formed by its support mounting boss. In this manner the handle can be rotated to press against two joists and keep them apart. If desired, this mechanism could be simplified by omitting one of the nuts and replacing the corresponding threaded stud with a cylindrical boss that rotates within its respective boss. Alternatively, this mechanism could be replaced by forming the support boss of each plate as a cylinder having an internal thread to engage the respective threaded stud.
The structure 214 is triangular in cross section and includes one corner which is a right angle 216, which corner, in use rests against a wall or other vertical surface or upright. Drill holes 218a and 218b are formed in front face 212a and rear panel 212b respectively. These facilitate the insertion of fixing bolts, such as 'rag bolts' or Rawlbolts (Trade Mark), when the joist hanger is placed against a wall (not shown), so that it can be permanently located against the wall.
Also shown are cut-outs 215 defined by forming an aperture in the prismatic structure 214 by folding tabs 217 and 219, so as to define joist supports 230, as shown in side view in
Other embodiments and items, shown in
Thus from the above it will be appreciated that use of the invention assists in the construction of buildings, particularly by speeding up the process of building and laying floors and ceilings and provides a flexible solution to problems suffered by existing building techniques.
It is understood that variation to the aforementioned embodiments may be made without departing from the scope of the invention.
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.