AU2022205141A1 - Stair stringer - Google Patents

Abstract

A staircase arrangement for forming a staircase between an upper storey and a lower storey. The staircase arrangement comprising a stringer beam having a top 5 end and a bottom end. A topmost tread or topmost tread support attachable to the upper storey. The topmost tread or topmost tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the topmost tread or topmost tread support comprises a channel for receiving the top end of the stringer beam. A bottom-most tread or bottom-most 10 tread support attachable to the lower storey. The bottom-most tread or bottom most tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the bottom-most tread or bottom-most tread support comprises a channel for receiving the bottom end of the stringer beam. Also, a plurality of intermediate treads or intermediate tread 15 supports arrangeable along the length of the stringer to form the staircase. 1 10 18a 12 18 18 16a { 26- 18b 22 H D 16 14 Figure 1

Description

10 18a 12

18 18 16a { 26- 18b 22 H D 16 14

Figure 1

Stair stringer

Technical field

The present invention relates to a stringer used to install stairs. In an embodiment, the stringer is a mono-stringer. The invention also relates to a system for installing stairs making use of the stringer.

Background

It is common for building to have stairs in order for a person to move from one level of the building to another level. The stairs can comprise a plurality of treads and risers which can be arranged in a series along a staircase. Usually, one horizonal tread positioned along the staircase leads to the next horizontal tread, until the required floor level is reached. The treads can be supported by one or more stringers. Each stringer can be mounted between the floors joined by the staircase. There can be a pair of stringers with the treads mounted therebetween, or there can be a mono-stringer (sometimes referred to as a centre-stringer or single stringer).

Mono type stringers comprise a single spine support beam to which the tread support brackets are fixed to support the step treads. The mono-stringer can be used in a staircase for aesthetic and or for practical purposes. A mono-stinger can have a sleek-looking modern design that provides a good final look to a construction. In some cases, the mono-stringer is practically preferred due to its ease of construction (possibly using less building materials since there is only one stringer), and or since it frees up some space around the staircase itself for e.g. furniture.

Typically, each mono-stringer is manufactured according to engineering drawings. The length and angle of the mono-stringer can be predetermined, and the location of each tread along stringer can be determined. It is usual for the spacing between floor and tread, and between each tread along the length of the staircase to be calculated so as to be approximately equal. The total rise can be calculated, and then divided by the number of requires steps. With this in mind, currently in the marketplace these structural staircase items are individually engineered and fabricated to suit each individual application. The lead times and costs incurred in relation to a bespoke manufactured staircases can become large. The staircase stringer once made may only be useable at one location and if a measurement error is made, the item has to be re-made. Furthermore, most staircases cannot be reused or re-purposed, which can be wasteful.

Staircases tend to be installed by professionals who take measurements and order io the materials. If a lay person or a person who does not install stairs frequently attempts to install the staircase, it can be complex. The complexity can come from the installation itself, but also from the initial calculations involved in stringer length, tread locations, etc. The person has to calculate the length(s) of the stringer(s) and the distances between treads as described above all while making sure that they adhere to building codes.

Accordingly, there exists a need for an improved mono-stringer which ameliorates or reduces at least some of the problems of the prior art. Preferably, the improved stringer is less complex to install than some prior art stringers.

Summary of invention According to a first aspect of the invention there is provided a staircase arrangement for forming a staircase between an upper storey and a lower storey, the staircase arrangement comprising a stringer beam having a top end and a bottom end, a topmost tread or topmost tread support attachable to the upper storey, the topmost tread or topmost tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the topmost tread or topmost tread support comprises a channel for receiving the top end of the stringer beam; a bottom-most tread or bottom-most tread support attachable to the lower storey, the bottom-most tread or bottom-most tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the bottom-most tread or bottom-most tread support comprises a channel for receiving the bottom end of the stringer beam; and a plurality of intermediate treads or intermediate tread supports arrangeable along the length of the stringer to form the staircase.

The staircase arrangement, in embodiments, can provide a convenient way of forming a staircase between an upper storey and a lower storey. The top end of the stringer can be fixed into the channel on the underside surface of the topmost tread or topmost tread support. The stringer can be pivotable about the top end which may allow for various lower storey floor heights to be accommodated by a fixed io length stringer. Once the stringer is in the desired position, it can be fixed to the floor. The plurality of treads (sometimes referred to as intermediate treads) can be attached along the length of the stringer at equal distances from one another.

The part of the staircase that is stepped on by the user in use can be referred to as a tread where the item is used without further modification. However, in some embodiments, the item in the stair case structure is a tread support, since an additional piece of material can be added to the tread support item to form the completed tread. In some embodiments, the tread support is referred to as a tread support bracket and is formed from metal such as steel. The additional piece of material added onto the support can be a tread material made of e.g. wood. Once in place on the tread support bracket, the metal and the wood together form the finished tread.

The staircase arrangement can be provided in a kit comprising the stringer beam, the topmost tread or topmost tread support, the bottom-most tread or bottom-most tread support, the plurality of intermediate treads or intermediate tread supports and screws and bolts for attaching the pieces as necessary. There can also be instructions provided for installation.

According to a second aspect of the invention there is provided a system for forming a staircase between an upper storey and a lower storey, the system comprising (a) measuring the distance between the upper storey and the lower storey; (b) attaching a topmost tread or topmost tread support to the upper storey, the topmost tread or topmost tread support having an upper surface for stepping on in use and an opposing underside surface comprising a topmost tread channel; (c) providing a stringer beam pre-cut to a length according to the measured distance between the upper storey and lower storey, wherein the length of the stringer beam is such that when a top end of the stringer beam is fixed into the topmost tread channel, the bottom end of the stringer beam rests on the floor of the lower storey and the stringer beam has an incline in the range of from about 26.5 degrees to about 45 degrees; (d) attaching a bottom-most tread to the lower storey, the bottom-most tread or bottom-most tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the bottom-most tread or bottom-most tread support comprises a channel for receiving the bottom end of the stringer beam; (e) placing a removable spacer onto the upper surface of the bottom-most tread or bottom-most tread support, the removable spacer set to tread distance in the range of from about 115 to 190mm; (f) positioning a tread or tread support onto the removable spacer; (g) attaching the tread or tread support to the stringer at the set tread distance to provide an attached tread or tread support; (h) placing a further removable spacer onto the attached tread or tread support; (i) positioning a further tread or further tread support onto the further removable spacer; (j)attaching the further tread or further tread support to the stringer at the set tread distance to provide a further attached tread or further attached tread support; (k) Repeating step (j) as many times as necessary until the distance between the further attached tread or further attached tread support and the topmost tread or topmost tread support is about the set tread distance.

Based on the distance measured at (a), the installer can determine how many treads or tread supports are required in the staircase based on the length of the stringer beam. The set distance between treads or supports can then be determined based on the teachings herein. The removable spacer fixed at the set distance can mean that an individual can install the staircase themselves using the items provided.

The present disclosure relates to a staircase arrangement and system for forming a staircase between an upper storey and a lower storey. The upper and lower storeys can be any two levels in a building or other construction between which a means for moving between the two levels is required. Typically, storeys between 1o building are spaced from about 3.5 to about 5.5 m. The average distance between storeys including ceiling height, floor thickness and building material is about 4.2m. However, the present arrangement and system could be used over shorter distances, for example where a doorway or veranda leads down to the ground. In these circumstances, the distance between the upper and lower storeys might be about 1m or 1.5 m (although it could be more or less). The lower storey can be the ground/earth. The lower storey can be a level in the building. The upper storey can be a platform, landing, balcony, porch, veranda or similar. The upper storey can be a level in a building.

The stringer is an elongate beam typically made from a strong material such as steel. The staircase described can be a mono-stringer, i.e. of the type having a single stringer beam running down the centre line of the staircase. However, there is no reason that the same technology and innovation described herein could not be applied to a staircase having a pair of stringers. Where there are pairs of stringers, it should be understood that the topmost tread or topmost tread support would comprise one channel for the top end of each of the stringers in the pair. The stringer beam has a top end which is closest to the upper storey. The stringer beam has a bottom end which is closest to the lower storey. The stringer beam can be provided in pre-cut lengths which can be used to accommodate various heights between upper and lower storey as described further below. The pre-cut stringer beam can be provided at a minimum length of 1.5m and a maximum length of 9.0m. The pre-cut stringer beams can be provided at any length with e.g. a 500 mm increment therebetween, such as 2.0m, 2.5m, 3.0m, and so on. The person installing the staircase can measure the distance between the upper and lower storey and then use a lookup table to determine which pre-cut stringer beam will suit their location. The length of the stringer required must be one in which the angle of incline of the stringer is within local building standard requirements. In Australia, the angle of the stringer must fall within the range of 26.5 degrees to 45 degrees which is in accordance with Australian building standards.

By way of example, a person can measure the distance between an upper and a lower storey using a tape measure or other measuring device. The distance can be measured to be e.g. 4m. The length of the required stringer can then be calculated io using a mathematical formula i.e. length of stringer = distance upper to lower storey/Sin(26.5 to 45 degrees). Alternatively, a lookup table can be provided either via an app or in paper form listing all possible measurements of the upper to lower storey distance and then providing possible stringer length options. Turning back to the example, with the top end of the stringer at a height of 4m, the length of the stringer can be about 5.7m (pitch 45 degrees) to about 9.Om (pitch 26.5 degrees). However, it should be understood that only some of these lengths are feasible given the building regulations around how many risers there can be in one staircase. Thus, while the installer can in theory select a stringer from the range that falls within 5.7-9.Om it is most likely that the choice will be more limited to the shorter lengths with the larger pitch. If there are multiple choices available, tthe choice might be one of personal preference in relation to how steep the stairs will be or how much available room there is for the stringer in the given space.

While the various treads including the topmost and bottom-most treads are referred to as treads once complete and ready for use. The treads once completed and ready for use can be any shape including quadrilateral shaped or shaped like a parallelogram. The treads once completed can be rectangular, rhomboidal or trapezoidal. The treads once completed can have rounded corners. It should be understood that in embodiments in which there are tread supports for additional tread material, the tread supports could be different in shape that the completed treads. The treads (horizontal) can be associated with risers (vertical). In some embodiments, the staircase does not have risers and instead there are openings between the completed treads. Some building codes require that where risers comprise openings, no opening should allow a 125 mm sphere to pass through between the completed treads. Each tread once completed has a length that extends across the staircase. Each tread has a width that is referred to as a going. Building codes can require that the going is in the range of from about 240-250 to 355 mm.

The treads or tread supports escalate along the stringer with each one in the sequence being at a greater height than the former. It should be understood that each tread support can be support surfaces for additional building material that can be applied to that support surface to complete the tread. The completed tread io might therefore comprise a metal support surface, onto which there is bolted a hardwood or other hard material surface for the person to step on in use. The material bolted onto the support surface to complete tread could be about 30 to 80 mm in thickness. The distance between a top surface of adjacent treads should be in the range from about 115 to about 190 mm. The number of treads required along the stairway is therefore a calculation based on the length of the stringer and the required spacing of the completed treads therealong, bearing in mind that the spacing between completed treads should be equidistant. Some building codes require that all risers and goings on the same flight of stairs should have uniform dimensions within a tolerance of ±5 mm. Some building codes require that a stairway have not more than 18 risers and not less than 2 risers in each flight.

The topmost tread or topmost tread support is located at the top of the stairway closest to the upper storey. The topmost tread or topmost tread support has an upper surface onto which downward pressure will be applied by a person stepping on it in use. The topmost tread or topmost tread support has an underside surface which is opposite to the upper surface. The topmost tread or topmost tread support is attachable to the upper storey. The topmost tread or topmost tread support can be attachable at a location at which the completed top tread will, once finished, be flush with the floor of the upper storey. The topmost tread or topmost tread support can be attached via its upper surface to the underside of the floor level. This arrangement is not preferred since downward pressure applied when stepping on the step is not counteracted by any forces holding the topmost tread or topmost tread support in place. Alternatively, the topmost tread or topmost tread support can be attached by its underside surface to the topside of the floor level. This arrangement is not preferred in some embodiments since any building material added to the top of the tread support surface to complete tread might not be flush with the upper storey floor lever. Further alternatively, the topmost tread or topmost tread support can be attached along a side wall of the topmost tread or topmost tread support. An advantage of this arrangement is that the bolts used to support the topmost tread are or topmost tread support under shear stress when a person steps on the step, which can provide structural stability.

The underside surface of the topmost tread or topmost tread support comprises a io channel for receiving the top end of the stringer beam. The channel can be formed by two objects being positioned on the underside of the topmost tread or topmost tread support spaced from one another by a distance just wider than the thickness of the stringer beam. The two objects can be welded to the underside of the topmost tread or topmost tread support. The two objects can be formed integrally with the topmost tread or topmost tread support. In some embodiments, the topmost tread or topmost tread support is a solid (or hollow) box shape with a channel cut out to provide the same effect. The top end of the stringer can be positioned in the channel and fixed to the topmost tread or topmost tread support. The fixing can be by a bolt or bolts that pass(es) through apertures in the channel walls and through the stringer. Advantageously, once fixed the stringer is able to pivot about the fixing point to allow for various positions of the stringer. Once the preferred position of the stringer is found, i.e. where the lower end of the stringer naturally rests on the floor of the lower storey under influence of gravity, the stringer can be fixed more firmly into position. The firmer fixing can be provided by tightening existing bolts, or by providing additional bolts. The channel can have an opening at the front face of the topmost tread or topmost tread support to allow for the stringer to be inserted and pivoted once fixed. The channel can be open or closed at the rear face of the topmost tread or topmost tread support.

Once the topmost tread or topmost tread support and stringer are in position, a bottom-most tread or bottom-most tread support can be provided. The bottom most tread or bottom-most tread support becomes the competed tread at the bottom of the stairway closest to the lower storey. The bottom most tread or bottom-most tread support has an upper surface onto which is applied the downward of a person stepping on it in use. The bottom most tread or bottom-most tread support has an underside surface which is opposite to the upper surface. The bottom most tread or bottom-most tread support is attachable to the lower storey.

The underside surface of the bottom-most tread or bottom-most tread support comprises a channel for receiving the bottom end of the stringer beam. The bottom most tread or bottom-most tread support can be positioned around the bottom end of the stringer beam and secured into position. The channel can be formed by a pair of arms extending from the bottom surface and receivable around the stringer 1o beam body. Brackets can be applied to the arms to fix the bottom most tread to the floor.

The height of the completed bottom most tread from the floor of the lower storey can be in the range from about 65 to 140m pending tread thickness. The thickness of the arms and or the location of the brackets can be adjusted to allow for the connection between tread and floor.

Once the stringer is in position between the topmost tread or topmost tread support and the bottom most tread or bottom-most tread support, a plurality of treads or tread supports are arrangeable along the length of the stringer to form the staircase as described above. There is typically no predrilling of holes for the treads or supports along the stronger body. There are typically no markings along the stringer to indicate where to locate the treads or supports. This is because each stringer can accommodate different numbers and locations of treads/supports.

Once the bottom-most tread or bottom-most tread support is in position, a removable spacer can be applied to the upper surface of the bottom-most tread or bottom-most tread support to set the next tread height. The removable spacer can be a jig, which holds the next tread in the series and guides the tool securing it to the stringer. The removable spacer is set to a fixed tread distance that is calculated by dividing height distance from upper to lower storey by the required number of steps. The required number of steps is calculated by assessing how many steps would be required for each of them to fall equidistant in the range of from about 115 to 190mm. In embodiments, the distance is not necessarily measured from the top surface of the bottom-most tread support to the top surface of the next adjacent tread support, because it must be borne in mind that each of the metal treads provided in the stairway can be a tread support onto which further building material can be added to finish the tread. Accordingly, the fixed tread distance is calculated based on the final completed height of the finished treads spaced from one another. It should also be noted with this in mind that not all tread spacings will be accommodatable by a given stringer length. Accordingly, a calculation is required to determined what set tread distance would work to accommodate all the building code requirements. This can be provided via an app or hardcopy lookup table. The io app or paper lookup table could be used to determine that the best set tread distance for a 6m stringer could be e.g. 130mm. With a spacing fixed to 130mm, the bottom most tread would be elevated from floor level by e.g. 110mm which would allow for tread upper surface modifications.

In order to fix the tread or tread support at the set tread distance, the tread or tread support can be position onto the removable spacer. In an embodiment, the removable spacer is a platform with a vertical shaft and a movable platform supported by a collar. Set to 130mm, the next tread or tread support in the series can rest on the platform while it is connected to the stringer. The tread or tread support can be configured on its underside to allow it to receive the stringer and be connected to the stringer. The connection to the stringer can be by screws through plates connected to the underside of the tread or tread support. The connection to the stringer can be by self-drilling screws that pass through the tread body or tread support bosy. The self-drilling screws can be tek screws that have a drill point. The tip of the tek screw therefore has the ability to drill its own hole. The process of mounting the treads or tread supports can then be repeated from that attached tread or attached tread support, by removing the spacer from the fixed tread or fixed tread support and locating it on the next tread or tread support in the series, and so on. This can continue all the way up the stairway as it is constructed until the topmost tread or topmost tread support is reached.

Whilst it is envisaged that the spacer is located firstly on the bottom most tread or bottom-most tread support and the stairway is built upwardly, it is conceivable that the spacer hangs from the topmost tread or topmost tread support and the same process is undertaken only building downwardly. This is slightly more cumbersome especially for large staircases where the upper storey is above head height, but it is within the spirit and scope of the invention.

Brief Description of the Figures Embodiments of the invention will now be described with reference to the accompanying drawings which are not drawn to scale and which are exemplary only and in which:

io Figure 1 is a schematic side view according to one embodiment.

Figure 2 is a table showing stringer length.

Figure 3 are photographs of an embodiment of the topmost tread support.

Figure 4 is a photograph of the stringer in the channel of the topmost tread support of Figure 3.

Figure 5 is a photograph of the bottom most tread support positioned on the stringer of Figure 4.

Figure 6 is a photograph of the bottom most plate.

Figure 7 is a series of photographs showing the placement of the intermediate tread supportsto build the staircase.

Figure 8 is a photograph of an embodiment of the removable spacer.

Figure 9 is a photograph of the removal spacer of Figure 8 when in use forming the staircase.

Detailed Description of Embodiments of the Invention Figure 1 shows a staircase arrangement for forming a staircase 10 between an upper storey 12 and a lower storey 14. The upper storey 12 and lower storey 14 can be any two levels in a building. The staircase 10 comprises at least one stringer 16. The stringer 16 is an elongate beam made from steel. The staircase 10 shown in Figure 1 is of the type having a single stringer beam 16 running down the centre line of the staircase 10. The stringer beam 16 has a top end 16a which is closest to the upper storey 12. The stringer beam 16 has a bottom end 16b which is closest to the lower storey 14.

The topmost tread support 18 is at the top of the stairway closest to the upper storey 12. The topmost tread support 18 has an upper surface 18a onto which io additional material will be added to complete the tread. In use, the upper surface will be the surface onto which a person steps in use. The topmost tread support 18 has an underside surface 18b which is opposite to the upper surface 18a. The topmost tread support 18 is attachable to the upper storey 12. The topmost tread support 18 can be attached along a side wall 18c of the topmost tread support 18.

As can be seen in Figure 3, the underside surface 18b of the topmost tread support 18 comprises a channel 20 for receiving the top end 16a of the stringer beam 16. The channel 20 is formed by two objects 20', 20" being positioned on the underside 18b of the topmost tread support 18 spaced from one another by a distance just wider than the thickness of the stringer beam 16. Each object 20'and 20" can be a U-shaped fin welded to the underside. The channel 20 has an opening at the front face of the topmost tread support 18 as can be seen most clearly in Figure 3A. The channel 20 allows for the stringer 16 to be inserted. The channel 20 can be closed at the rear face of the topmost tread support 18 as can be seen in Figure 3B.

As can be seen in Figure 4, the top end 16a of the stringer 16 can be positioned in the channel 20 and fixed to the topmost tread support 18. The fixing is a bolt or bolts that passes through apertures in the channel walls and through the stringer 16. Once fixed the stringer 16 is able to pivot about the fixing point P in the direction of the arrows shown in Figure 4. The lower end 16b of the stringer 16 can be positioned so as to rest on the floor 14 of the lower storey under influence of gravity. In Figure 4, the stringer 16 is shown as having a flat surface on the floor 14. However, in some embodiments only a part of the flat cut bottom end of the stringer will rest on the floor and there may be a gap between the floor 14 and the flat cut end.

The bottom most tread support 22 is at the bottom of the stairway 10 closest to the lower storey 14. The bottom most tread support 22 has an upper surface 22a onto which additional material will be added to complete the tread. In use, the upper surface will be the surface onto which a person steps in use. The bottom most tread support 22 has an underside surface 22b which is opposite to the upper surface 22a. The bottom most tread support 22 is attachable to the lower storey 14.

As can be seen in Figure 6A, the underside surface 22b of the bottom-most tread support 22 comprises a channel 24 for receiving the bottom end 16b of the stringer beam 16. The bottom most tread support 22 can be positioned around the bottom end 16b of the stringer beam 16 as shown in Figure 6B. The tread support 22 can then be secured into position using bracket 26. The channel 24 can be formed by a pair of arms 24', 24" extending from the bottom surface 22b and receivable around the stringer beam body 16. The bracket 26 (of which there can be one or more than one) can be applied to the arms 24' and or 24" to fix the bottom most tread support 22 to the floor 14.

Once the stringer 16 is in position between the topmost tread support 18 and the bottom most tread support 22, a plurality of intermediate treads supports 26 are arrangeable along the length of the stringer to form the staircase as described above. The sequence of their addition is shown in Figure 7 from A to D. The tread supports 26 escalate along the stringer 16 with each one in the sequence being at a greater height than the former.

It should be understood that each tread supports 18, 22, 26 are support surfaces for additional building material that will be applied to that support surface to complete the treads. An example of this is shown in Figure 1 on tread surface 18a by a dotted line. The completed tread might therefore comprise a metal support surface, onto which there is bolted a hardwood or other hard material surface for the person to step on in use. There can be other surfaces applied such as a non slip surface applied if required.

The distance between a top surface of adjacent treads 18,26, 26,26 or 26,22, should be in the range from about 115 to about 190 mm. The number of tread supports 26 required along the stairway 10 is therefore a calculation based on the length of the stringer 16 and the required spacing of the treads 26 therealong, bearing in mind that the spacing between all treads 18, 26, 22 such be equidistant. There is typically no predrilling of holes for the tread supports 26. There are typically no markings along the stringer 16 to indicate where to locate the tread supports 26. This is because each stringer 16 can accommodate different numbers io and locations of tread supports.

The stringer beam 16 can be provided in pre-cut lengths which can be used to accommodate various heights between upper 12 and lower storey 14. The person installing the staircase can measure the distance H between the upper 12 and lower storey 14 and then use a lookup table to determine which pre-cut stringer beam will suit their location. An example of a lookup table is provided in Figure 2. This can be provided in a manual/instruction booklet, or it could be provided in app format (electronic). By way of example, the distance H could be measured to be 4m. The length of the required stringer 16 can then be looked up (Table of Figure 2) and it can be found that the length of the stringer can be about 5.7m (pitch 45 degrees) to about 9.Om (pitch 26.5 degrees). The installer can select a stringer from the range that falls within 5.7-9.0m. The installer could select the 6.Om long stringer for installation. Alternatively, if the distance H could be measured as 1m. The length of the required stringer 16 can then be looked up (Table of Figure 2) and it can be found that the length of the stringer can be about 1.4m (pitch 45 degrees) to about 2.2m (pitch 26.5 degrees). The installer can select a stringer from the range that falls within 1.4m to 2.2m. The installer could select the 2.Om long stringer for installation.

The height of the bottom most tread support 22 from the floor 14 of the lower storey can be in the range from about 60 to 140m. The thickness of the arms 24, 24" and or the location of the bracket(s) 26 can be adjusted to allow for the connection between tread support 22 and floor 14. Once the bottom-most tread support 22 is in position, a removable spacer 28 can be applied to the upper surface of the bottom-most tread support 22 to set the next tread height. An example of a removable spacer 28 can be seen in Figure 8. The removable spacer 28 is set to a fixed tread distance D (refer Figure 1) that is calculated by dividing the height distance from upper to lower storey by the required number of steps (treads) (taking into account additional tread material in any completed tread).

As shown in Figure 8 the removable spacer comprises a base 30 with a vertical shaft 32 and a movable platform 34 supported by a collar 36. Set to e.g. D=130mm, the next tread 26 in the series can rest on the platform 34 while it is io connected to the stringer 16 (refer to Figure 9 although stringer 16 is omitted for clarity). The tread 26 can be configured with fins underside to allow it to receive the stringer 16 and be connected to the stringer 16.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Any promises made in the present description should be understood to relate to some embodiments of the invention and are not intended to be promises made about the invention as a whole. Where there are promises that are deemed to apply to all embodiments of the invention, the applicant/patentee reserves the right to later delete them from the description and does not rely on these promises for the acceptance or subsequent grant of a patent in any country.

Claims (1)

1. CLAIMS 1. A staircase arrangement for forming a staircase between an upper storey and a lower storey, the staircase arrangement comprising a stringer beam having a top end and a bottom end, a topmost tread or topmost tread support attachable to the upper storey, the topmost tread or topmost tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the topmost tread or topmost tread support comprises a channel for receiving the top end of the stringer beam; io a bottom-most tread or bottom-most tread support attachable to the lower storey, the bottom-most tread or bottom-most tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the bottom-most tread or bottom-most tread support comprises a channel for receiving the bottom end of the stringer beam; and a plurality of intermediate treads or intermediate tread supports arrangeable along the length of the stringer to form the staircase.

   2. The staircase arrangement of claim 1, wherein a topmost tread support, a bottom-most tread support and intermediate tread supports are used to complete the staircase, and wherein each of the supports is modified with additional material on its top surface thereof to form completed treads.

   3. A system for forming a staircase between an upper storey and a lower storey, the system comprising (a) measuring the distance between the upper storey and the lower storey; (b) attaching a topmost tread or topmost tread support to the upper storey, the topmost tread or topmost tread support having an upper surface for stepping on in use and an opposing underside surface comprising a topmost tread channel; (c) providing a stringer beam pre-cut to a length according to the measured distance between the upper storey and lower storey, wherein the length of the stringer beam is such that when a top end of the stringer beam is fixed into the topmost tread channel, the bottom end of the stringer beam rests on the floor of the lower storey and the stringer beam has an incline in the range of from about 26.5 degrees to about 45 degrees; (d) attaching a bottom-most tread to the lower storey, the bottom-most tread or bottom-most tread support having an upper surface for stepping on in use and an opposing underside surface, wherein the underside surface of the bottom-most tread or bottom-most tread support comprises a channel for receiving the bottom end of the stringer beam; (e) placing a removable spacer onto the upper surface of the bottom-most tread or bottom-most tread support, the removable spacer set to a tread io distance in the range of from about 115 to 190mm; wherein the set tread distance is calculated by using the measurement from step (a), the required number of treads or tread supports and the incline of the stringer; (f) positioning a tread or tread support onto the removable spacer; (g) attaching the tread or tread support to the stringer at the set tread distance to provide an attached tread or tread support; (h) placing a further removable spacer onto the attached tread or tread support; (i) positioning a further tread or further tread support onto the further removable spacer; (j)attaching the further tread or further tread support to the stringer at the set tread distance to provide a further attached tread or further attached tread support; (k) Repeating step (j) as many times as necessary until the distance between the further attached tread or further attached tread support and the topmost tread or topmost tread support is about the set tread distance.

   4. The system for forming a staircase according to claim 3, wherein the set tread distance is provided by a lookup table that allows a user to enter the measurement from step (a) to determine the length of stringer required and the required number of completed treads.

   5. A kit comprising the items from claim 3 including the stringer beam, the topmost tread or topmost tread support, the bottom-most tread or bottom most tread support, the plurality of intermediate treads or intermediate tread supports and a plurality of fasteners such as screws and bolts for attaching the pieces as necessary provided together with instructions provided for installation including a look up table in accordance with claim 4.

   10 18a 12 2022205141

   18c 18 16a 26 18b 22 H D 16 14 16b

   Figure 1

   Stringer Stringer Distance H: upper to lower length length 2022205141

   storey (m) (max) (m) (min) (m) 4 5.7 9.0 3.5 4.9 7.8 3 4.2 6.7 2.5 3.5 5.6 2 2.8 4.5 1.5 2.1 3.4 1 1.4 2.2

   Figure 2

   18b

   18c 20’ A 2022205141

   20’’

   20

   18 20’ 20 20’’

   18a 18 20’’ 20’

   20

   Figure 3

   P

   Figure 4 16

   16b

   16

   Figure 5 22

   22a

   22b 24’ 2022205141

   24’’ 26

   24

   Figure 6A

   16b 24 22a 26

   Figure 6B

   26 22 2022205141

   26 26 A 22

   18 B

   26 26 18 26 26 22 26 26 26 22 C

   D Figure 7

   Figure 8 30 D 36

   32

   36

   30

   Figure 9 34