GB2509373A

GB2509373A - Formwork for steps

Info

Publication number: GB2509373A
Application number: GB1319664.7A
Authority: GB
Inventors: Steven Jeffrey Willis; Neil Martin Hadler
Original assignee: PERMASHUTTER Ltd
Current assignee: PERMASHUTTER Ltd
Priority date: 2012-11-06
Filing date: 2013-11-06
Publication date: 2014-07-02
Also published as: GB2509373A9; GB201319664D0; GB201220000D0

Abstract

A formwork 1 for the construction of a flight of steps 2 on a sloping surface such as an embankment comprises at least one formwork unit 11. The or each formwork unit comprises a pair of lateral stringer elements 14 connected by a plurality of transversely extending step units 12. Each step unit comprises a riser panel 13, which together with the stringer elements and the sloping surface defines a volume to receive a filler material such as concrete. The riser panels may be pivotally attached to the stringer elements. The formwork may include a tray 21 for receiving concrete to form a landing unit. Sockets 32 may receive handrails. The formwork may be fixed to the sloping surface via anchors and may be formed from plastic. A method of constructing a flight of steps is also claimed.

Description

FORM WORK FOR STEPS

The present invention relates to formwork to facilitate the construction of flights of steps.

More particularly, but not exclusively, it relates to apparatus and methods for constructing flights of paved steps on an existing sloping surface, such as an embankment.

It is often desirable to provide safe access for pedestrians up and down a natural or artificial slope, particularly where the slope might become unsafe in wet conditions, and especially where a gradient of the slope would be too great for a simple gravel, tarmac or paved pathway to be suitable. In such situations, flights of steps would be preferable, particularly where access is required by personnel carrying loads, such as workmen. One example of a situation where flights of steps would be considered necessary would be where a road on a bridge crosses a railway line, a trunk road in a cuffing or a waterway.

Access from the bridge down an embankment to the trackside, roadside or a towpath * would be desirable, but for safety reasons, worknen carrying equipment should be *..** * * * provided with a safe set of steps down the embankment, ideally steps that are paved and * provided with hanclrails or the like.

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* The construction of such steps is, however, not a straightforward matter. Constructing horizontal tread surfaces on a sloping surface requires care. Throughout the construction process, the workers constructing the steps would be working 011 the slope in difficult conditions. It might even be necessary to restrict passage along the railway, road, towpath, etc. at the foot of the steps, for the safety of the construction workers. Additionally, conventional methods for constructing such flights of steps can be time consuming, and expensive in labour costs.

It is hence an object of the present inventors to provide apparatus and methods for constructing flights of steps or stairways on an existing slope, which are more reliable, more rapid and ideally safer and more cost-effective than existing approaches.

According to a first aspect of the present invention, there is provided formwork for the construction of a flight of steps sited on a sloping surface, comprising at least one elongate stair formwork unit locatable on said surface, the or each said stair formwork unit comprising a pair of lateral stringer elements coimected by a plurality of transversely extending step units, each step unit comprising riser panel means alignable vertically in use, such that a volume defined by the lateral stringer elements, a step unit and said sloping surface is adapted to receive a constructional filler material to support a tread surface of the flight of steps. S. *S

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In a first embodiment, each step unit comprises riser panel means mounted pivotably * between the respective lateral stringer elements.

* S S * ** * S * . * ** The formwork may thus be adjusted to co-operate with a particular gradient of the sloping * 4 * * S. surface.

In a second embodiment, each step unit comprises riser panel means and tread panel means so connected as to be alignable respectively vertically and horizontally in use, each tread panel means being provided with at least one aperture to receive a constructional filler material into a step interior defined by the tread panel means, the riser panel means, the lateral stringer elements and the sloping surface on which the formwork is located.

Preferably, the stair formwork unit comprises a plurality of said step units conjoined in series.

Advantageously, the pair of lateral stringer elements then each extends along a respective opposite edge of the series of conjoined step units.

In either embodiment, the formwork preferably comprises a plurality of said stair formwork units, connected or connectable in series to form a basis for a continuous stairway.

Preferably, the formwork further comprises at least one landing formwork unit co-operable with at least one stair formwork unit and comprising floor means having upstanding wall * * means extending around a perimeter thereof, so as to define tray means adapted to retain a : constructional filler material when the floor means is located on a substantially level * surface.

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* ** Advantageously, the or each landing formwork is provided with a plurality of upstanding * * S. rib means extending across the floor means so as to space a body disposed on top of the rib means from the floor means.

An upper, in use, end of the formwork may comprise a landing formwork unit.

A lower, in use, end of the formwork may comprise a landing formwork unit.

The formwork may comprise at least one landing formwork unit having stair formwork units extending upwardly and downwardly in use therefrom.

Preferably, the formwork further comprises handrail means.

The handrail means is advantageously mounted directly to the formwork.

The formwork may be provided with socket means adapted to receive the handrail means, mounted directly to the formwork.

Preferably, the formwork comprises means to secure it to an underlying ground surface.

Advantageously, the means to secure the formwork comprises apertures in each fomiwork unit, adapted for elongate anchoring members to be passed therethrough into the underlying ground. * .

* * . . Said apertures may be provided in the or each stair formwork unit. * ** * * . * **

Optionally, the apertures may be provided in one or more tread panel means of the or each stair formwork unit.

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Additionally or alternatively, said apertures may be provided in the or each landing fomiwork unit.

Preferably, the formwork comprises a plastics material.

Advantageously, the formwork comprises a thermoplastics material.

Optionafly, the forrnwork comprises a recycled plastics material.

According to a second aspect o1 the resent invention, there is provided formwork for the construction of a flight of steps sited on a sloping surface, comprising at least one elongate stair formwork unit locatable on said surface, the or each said stair formwork unit comprising a pair of lateral stringer elements connected by a plurality of transversely extending step units, wherein the formwork further comprises attachment means for handrail means for the flight of steps to be mounted directly to the formwork.

According to a third aspect of the present invention, there is provided a flight of steps comprising a forrnwork as described in either the first or the second aspect above. S..*t * *

According to a fourth aspect of the present invention, there is provided a method of *.*.*. * *

* *. * constructing a flight of steps on a sloping surface, comprising the method steps of * ** providing formwork as described in either the first or the second aspect above, assembling * * * * ** said formwork on the sloping surface, filling said formwork with a constructional filler material, and locating paving means on to an upper surface of the constructional filler material.

The constructional filler material may be so filled as to stand slightly proud before the paving means is located thereon.

Preferably, the method of constructing a flight of steps comprises the further method step of preparing the sloping surface by grading it appropriately to receive the stair formwork units and landing formwork units of the formwork.

Advantageously, the method of constructing a flight of steps comprises the further method step of locating reinforcement means for the constructional filler material in or under the formwork prior to filling with the constructional filler material.

The method of constructing a flight of steps may comprise the further method step of mounting handrail means for the flight of steps directly to the formwork.

According to a fifth aspect of the present invention, there is provided formwork for the r * construction of a flight of steps sited on a sloping surface, comprising at least one elongate * stair formwork unit locatable on said surface, the or each said stair formwork unit * * * comprising a pair of lateral stringer elements extending along opposite edges of a series of *..*** * * conjoined step units, each step unit comprising a riser element connected to a tread *:::* element so as to be alignable respectively vertically and horizontally in use, wherein each tread element is provided with at least one aperture through which a constructional filler material may be delivered into a step void defined by the tread element, the riser element, the lateral stringer elements and the sloping surface on which the stair formwork unit is located.

Preferably, the formwork comprises a plurality of said stair formwork units, connected or connectable in series to form a basis for continuous stairway.

Advantageously, the formwork comprises at least one landing formwork unit connectable to at least one stair formwork unit and comprising floor means having upstanding wall means extending around its perimeter so as to define fray means adapted to retain a construction filler material when the floor means is located on a substantially level sub-surface.

In all aspects of the present invention, the constructional filler material preferably comprises concrete.

Embodiments of the present invention will now be more particularly described by way of example and with reference to the accompanying drawings, in which: Figure 1 is a plan view from above of a linked pair of stair formers of a formwork r * embodying the present invention; * 0 Figure 2 is a frontal elevation of the pair of stair fonners shown in Figure 1; Figure 3 is a right side elevation of the pair of stair formers show in Figure 1; *.** .. * 0

* tot Figure 4 is an isometric vicw of a landing former of a formwork embodying the * ** present invention; * * 0 * *. -Figure 5 is a plan view from above of the landing former of Figure 4 with handrail sockets fitted; Figure 6 is a frontal elevation of the landing former of Figure 4; Figure 7 is a side elevation of the landing former of Figure 4; Figure 8 is an isometric view of an assembled formwork embodying the present invention; Figure 9 is an isometric view of the formwork of Figure 8, with handrails in position; Figure 10 is an exploded isometric view of the formwork of Figures 8 and 9, including handrails; Figure 11 is an isometric view of a completed stairway constructed using the formwork of Figure 8; Figure 12 is an isometric view of the stairway of Figure 11, with handrails separated to show a remainder of the stairway more clearly; Figure l3is a frontal elevation of the stairway of Figure 11; Figure 14 is a plan view from above of the stairway of Figure 11; Figure iSis a side elevation of the stairway of Figure 11; Figure 16 is an isometric view of a modular stair former embodying the present invention; Figure 17 is an isometric view of the modular stair former of Figure 16 incorporated into a stairway; and * Figure 18 is a schematic side elevation of the modular stair former of Figure 16 in * * use.

* * **** * *.*.* * * * ** Referring now to the Figures, and to Figures 1 to 3 in particular, a pair of stair formers 11 * * * * ** are shown linked together as a portion of a formwork 1 for a stairway 2 (see below for the complete fonnwork 1 and stairway 2, particularly Figures 8 and 1 1). Each stair former 11 comprises a series of steps, each step defined by a horizontal tread panel 12 and a vertical riser panel 13, connected in an alternating sequence. A stringer 14 extends along each side of the stair former 11, mounted to an edge of each tread panel 12 and riser panel 13.

The riser panels 13 are continuous in this embodiment, whereas the tread panels 12 each include three large rectangular openings 15, the ffinction of which is described below.

These openings 15 are separated by narrow slats 16. Several of the tread panels 12 on each stair former 11 are provided with round apertures 17, extending through these slats 16, through which an elongate metal rod or "pin" may be inserted, generally vertically, to anchor the stair former 11 to an underlying ground surface or sub-surface.

The stringers 14 may comprise relatively broad side panels as shown, or they may comprise narrower strips to which separately formed broader side panels may be mounted.

Indeed, in some embodiments, each step (or even each tread panel and each riser panel) and each stringer are separately moulded and assembled into stair formers 11 as shown.

Such a modular approach has the advantage that the depth of the tread panels 12 and/or the height of the riser panels 13 can be selected to produce a range of stair formers 11 having different gradients. I. **

a The stair formers 11 are in most embodiments made from recycled plastics materials, S 5555. * .

ideally recycled therinoplastics materials, such as polypropylene. They may be produced 55*5*5 4 by injection moulding or vacuum forming, as convenient. * S. * S * * as

Most stairways 2 in outdoor situations will not comprise a single continuous flight of steps. Instead, they will have one or more intermediate horizontal landings between separate flights of steps, and it will often be appropriate to provide a horizontal landing at a top and a bottom of the stairway 2, rather than users entering and exiting the flights of steps directly.

The formwork 1 of the present embodiment therefore also comprises a plurality of landing formers 21, as shown in Figures 4 to 7. Each landing former 21 comprises a rectangular flat floor panel 22, with a shallow wall 23 rising from each edge of the floor panel 22, forming a tray structure. A plurality of apertures 24 extend through the floor panel 22, so that a "pin" may be inserted therethrough to anchor the landing former 21 to an underlying ground surface or sub-surface.

Figure 4 illustrates two further features of the landing former 21. Several transverse ribs extend across the floor panel 22, the function of which is described below. (NB the ribs are not shown in the remaining Figures for clarity; they may not be present at all in other embodiments of the invention).

As shown in both Figure 4 and Figure 6, one of the longer walls 23 of the landing former 21 has a connection portion 26 of reduced height. This connection portion 26 has a width r corresponding to that of the stair formers 11, and is connected to an upper end of a * descending stair former 11 in the completed formwork 1 (see Figures 8 and 10).

Omitted from Figure 4 (and from Figures 1 to 3) but shown in Figures 5 to 7 are a number * of handrail sockets 32, bolted to the walls 23 of the landing former 21. These sockets 32 * S S * S. allow a handrail 3 of conventional form to be fitted to the formwork 1, rather than the handrail 3 having to be implanted in a ground surface adjacent a completed stairway, as now.

For the stair formers ii, such handrail sockets 32 may be mounted directly to the respective lateral stringer 14, or where the lateral stringer 14 comprises separately-formed side skirts, the handrail sockets 32 may be bolted through the side skirts to the stringer proper, thus helping to secure the side skirts in place.

A completed formwork I is shown in Figure 8. In Figure 9, the formwork 1 is shown fitted with a handrail 3, although more often the handrail 3 would not be fitted at this stage of the process. In Figure 10, the formwork I and handrail 3 are shown in an exploded view to show how the components of the formwork 1 link together.

The particular formwork I illustrated comprises four stair formers 11 a, b, c, d and three landing formers 21a, b, c. A first landing former 21a is located at a top of the sloping surface, with two linked stair formers 1 la, 1 lb extending in series down-slope from the connection portion 26 of the first landing former 21a. A second landing former 21b is located partway down the sloping surface, a lowermost riser panel 13 of the stair former v. 1 lb abutting against a respective wall 23 of the landing former 21b. Two thrther linked stair formers 1 lc, lid extend in series down-slope from the connection portion 26 of the ee * . second landing former 21 b. A third landing former 2 le is located at a foot of the sloping surface; again, a lowermost riser panel 13 of the stair former lid abuts against a respective * * wall 23 of the landing former 2ic. * * *%

Handrail sockets 32 are positioned as required on the walls 26 of the landing formers 12a, 1 2b, 1 2c and on the stringers 14/side skirts of the stair formers 11 a, 11 b, lie, lid, to receive the handrail sections 31 making up a desired handrail 3 arrangement. In the particular example shown in Figures 8 to 10, the handrail 3 extends only along one side of the stair formers 1 la, 1 ib, 1 lc, 1 ld and so the handrail sockets 32 on the respective stringers 14 are not visible in this view.

A preferred procedure for installing the formwork 1 for constructing a stairway 2 on a sloping surface such as an embankment is as follows.

Topsoil and turf is stripped from the area to be occupied by the stairway 2, and is placed to one side. The stripped area is graded as necessary to suit the particular arrangement of sloping steps and level landings required. Optionally, a bed of crushed stone or the like may be laid in the graded, stripped area, for example as reinforcement or where the stability of a sub-surface of the area may be questionable.

The lowermost landing former 21c is located in position at the bottom of the embankment, and is pinned in position with long metal rods or "pins" inserted through the apertures 24 in its floor panel 22 and deep into the embankment. is U I. *

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The two lower stair formers 11 d, 11 c are then located on the embankment with the lowest sUnS stair former lid butted up against the landing former 2lc. Positions for temporary holes or "toes" for the stair formers lid, lie are marked with pins or with spray paint, and the S *S stair formers lid and 1 ic are then marked and put to one side. The toes are excavated manually. Ideally, one toe is dug at the bottom of every eight steps.

Panels of steel mesh reinforcement/rebar are then placed on the subsurface beneath the location of the stair formers lid, I ic, and the stair formers lid, lie are placed back in position. Further panels of the steel mesh reinforcement/rebar are placed within the landing former 21 c, supported on the ribs 25 (where present), so that they are raised above the floor panel 22.

Metal "pins" are then inserted, through the apertures 17 in the tread panels 12 of each stair former lid, 1 ic and deep intO the embankment, to secure the stair formers I ld, lie in position.

The intermediate landing former 2lb is then located on a levelled portion of the stripped area of the embankment, with its connection portion 26 aligned with an upper end of the respective stair former lie. The intermediate landing former 21 b is then pinned in position as described above.

The two upper stair formers 1 ib, 1 Ia are located in the embankment, with the lower of the two 11 b butted up against the intermediate landing former 21 b. As for the two lower stair :. formers lid, lie, positions for the "toes" are marked, the stair formers 11 b, 11 a are placed * * to one side and the required toes are dug out. * * *

* :" Further panels of steel mesh rebar are placed in the sub-surface beneath the location for the * stair formers 1 ib, I la and in the intermediate landing former 21 b. The stair formers 1 lb. 1 la are then replaced in position and pinned in position as above.

The uppermost landing former 2 la is located on a levelled portion of the stripped area of the embankment, with its connection portion 26 aligned with an upper end of the respective stair former 1 la. The uppermost landing former 21a is then pinned in position as described above, and panels of steel mesh rebar are placed within it, as for the other landing formers 21c, 21b.

Where the side skirts are formed separately from the stringers 14 proper, they are mounted to the respective stringers 14 at this stage. The required handrail sockets 32 are then fixed to the stair formers ha, lib, lie, lid and the landing formers 2ia, 21b, 21c, where appropriate clamping the side skins between the handrail sockets 32 and the respective stringer 14 ofthe stair former 1 la, 1 Ib, 1 Ic, 1 Id.

The formwork 1 is now in position, as shown in Figures 8 to 10.

In the next stage, the formers 11, 21 are sequentially filled with concrete, starting from the bottom of the embankment. The landing formers 21a, 21b, 21c are simply filled with concrete, level with a top of the reduced height wall 23 at the connection portion 26. The concrete thus encloses the panels of mesh rebar. * . a * *

* * . The large rectangular openings 15 in each tread panel 12 allow concrete to be poured into * : * an interior of each step, defined between the lateral stringers 14/side skirts, the respective * riser panel 13, the tread panel 12 and the underlying sub-surface. Each step of each stair *: *: :* former 11 is thus filled with concrete surrounding the respective panels of mesh rebar.

The concrete should also flow into the "toes" dug into the embankment at intervals beneath the stair formers II.

Ideally the concrete should be poured until in each opening 15 it stands proud by about 10 millimetres above a level of the tread panel 12.

Again, starting from the bottom of the embankment, conventional paving slabs 41 are bedded onto the concrete in each former 11, 12 and aligned neatly, as shown in Figures Ii to 15, to create a tread surface for the finished stairway 2. It may be more convenient to fill the lowermost landing former 21c and the two lower stair formers 1 ld, lie with concrete and then bed down the respective paving slabs 41 thereon, before proceeding to filling and paving the intermediate landing former 21b and the upper two stair formers 1 lb. I la, and then the uppermost landing former 21a in turn. (NB: the presence of the connection portion 26 of the landing formers 21 makes it far easier for paving slabs 41 on the landing former 21 to be laid continuously with paving slabs 41 on the top tread panel 12 of the stairway former 11).

Once the stairway 2 is complete, as in Figure 12, the handrail sections 31 can be fitted into the respective handrail sockets 32 to form the handrail 3, as in Figure 11. The preferred approach would be to fit handrail posts into the handrail sockets 32 and to tighten up the r:* respective fittings, before rails for the handrails are fitted between the handrail posts (the * * continuous runs of handrail sections 31 shown in Figure 12 are representative only; such * : large sections 31 would not be practical to pre-assemble and handle in practice). *.... S *

*: *: :* The stripped topsoil and turf are then replaced, producing a paved stairway 2 with a handrail 3, extending up and down the embankment to provide safe, convenient access in either direction.

Note: the particular stairway 2 shown has a handrail section 31 completely enclosing the uppermost landing former 21 a, which would for example be suitable for a viewing platform. For a conventional two-way stairway 2, the respective handrail section 31 would naturally have a gap for access on and off the uppennost landing former 21 a, as is shown for the lowermost landing former 2lc.

Figures 13 to 15 show ftirther views of the finished stairway 2, Figure 14 emphasising the continuous paved surface provided, for example.

As shown in Figure 15, this example stairway 2 has a relatively shallow overall gradient.

However, using stair formers 11 with taller riser panels 13 or shallower tread panels 12 would allow considerable variation in the slopes on which these formworks 1 can be employed.

A modular stair former 51 is shown in Figures 16 to 18. The modular stair former 51 is usable in place of the stair forme+ 11 shown in Figures 1 to 3, in formwork arrangements such as that shown in Figures 8 to 10. *e * . . * *

* . . The modular stair former 51 comprises a pair of elongate modular stringers 54, extending r parallelly and connected by several modular riser panels 53. Each rectangular modular *:" riser panel 53 is provided on opposing shorter edges of the panel 53 with a pair of support *: *: :* studs 55, each spaced the same distance from a longer edge of the panel 53 and extending in the plane of the panel 53. The support studs 55 are each received in a respective aperture 56 in a respective stringer 54. The support studs 55 each have a transverse terminal portion having a profile corresponding to that of the aperture 56.

The modular riser panels 53 are thus suspended from the stringers 54 by the support studs 55. In an in-use configuration as shown, the transverse terminal portion of each support stud 55 overlaps the periphery of the aperture 56, securing the panel 53 to the stringer 54.

However, the panel 53 is able to pivot on the support studs 55, and in an alignment roughly at right angles to that shown, the transverse terminal portion of the support stud 55 aligns with the respective aperture 56, and may be passed through the aperture 56. The modular riser panels 53 can thus conveniently be mounted to the modular stringers 54.

The main advantage of this arrangement is that the modular riser panels 53 can be pivoted relative to the stringers 54, allowing them to extend vertically on a range of different underlying slopes, rather than the stair former 11 having to be produced in many different configurations or the underlying ground surface having to be prepared to match the stair former 11.

The modular stair former 51 also differs from the stair former 11 of Figures 1 to 3 in that it has no tread panels 12.

* ***.. * .

The modular stair former 51 is used as described above for the stair riser 11, except that ***.* * * * : ** . when concrete is poured into the modular stair former 51, it is poured into a series of *: " troughs each defined by the two modular stringers 54, two adjacent modular riser panels 53 and the underlying ground surface. The concrete is filled up to a level of a top edge of a lower of the respective modular riser panels 53, standing slightly proud if possible. As shown in Figure 17, paving slabs 41 may then be bedded on top of the concrete to form a continuous paved surface. As shown in Figure 18, the paving slabs 41 form a tread surface which is sufficiently well supported by the upper edges of the riser panels 53 together with the concrete that they retain, that no tread panels 12 are required.

The modular stair former 51 may thus be used in place of the stair former 11 (combined with landing formers 21 such as that shown in Figures 4 to 7) in any of the formworks 1 shown and described above.

As can be seen, the formworks 1 of the present invention remain in place as part of the stairway 2, anchoring it securely in position. Since the formworks I are made from recycled plastics, they should have long lifetimes. Even if a formwork 1 should eventually degrade and weaken, the reinforced concrete filling the formwork 1 will continue to support the paved surface. Use of recycled plastics materials also greatly reduces the "carbon footprint" of the formwork 1.

The handrail 3 is securely anchored into the stairway 2, not requiring separate installation.

This on its own is a major simplification of the conventional approach, saving significant amounts of time, as well as giving a more reliable result.

* ..... * .

The formwork 1 is light and easy to transport and handle, and the method of installation is *... .. * *

* . * straightforward and rapid. Installation times using the formwork I are as low as one-fifth * * :* of those for conventional methods, producing major cost savings.

A wide range of gradients can be achieved (probably between 1:1 and 1:4) and the formwork 1 can be made in a variety of widths as required. *. ** * * . * . ***.* * * *

*.. ** * * * S. .*.. * S * S. Se S S Se

Claims

CLAIMS1. Formwork for the construction of a flight of steps sited on a sloping surface, comprising at least one elongate stair formwork unit locatable on said surface, the or each said stair formwork unit comprising a pair of lateral stringer elements connected by a plurality of transversely extending step units, each step unit comprising riser panel means alignable vertically in use, such that a volume defined by the lateral stringer elements, a step unit and said sloping surface is adapted to receive a constructional filler material to support a tread surface of the flight of steps.
2. Formwork as claimed in claim 1, whcrcin each step unit compriscs riser panel means mounted pivotably between the respective lateral stringer elements.
3. Formwork as claimed in claim 1, wherein each step unit comprises riser panel means and tread panel means so connected as to be alignable respectively vertically and horizontally in use, each tread panel means being provided with at least one aperture to receive a constructional filler material into a step interior defined by the * tread panel means, the riser panel means, the lateral stringer elements and the * sloping surface on which the formwork is located.* .* *.. * SS

****.S **.*,
4. Formwork as claimed in claim 3, wherein the stair formwork unit comprises a *:*:: plurality of said step units conjoined in series.
5. Formwork as claimed in any one of the preceding claims, comprising a plurality of said stair formwork units, connected or connectable in series to form a basis for a continuous stairway.
6. Formwork as claimed in any one of the preceding claims, further comprising at least one landing formwork unit co-operable with at least one stair formwork unit and comprising floor means having upstanding wall means extending around a perimeter thereof, so as to define fray means adapted to retain a constructional filler material when the floor means is located on a substantially level surface.
7. Formwork as claimed in claim 6, wherein an upper andlor a lower end, in use, of the formwork comprises a landing formwork unit.
8. Formwork as claimed in either claim 6 or claim 7, comprising at least one landing formwork unit having stair formwork units extending upwardly and downwardly in use therefrom.
9. Formwork as claimed in any one of the preceding claims, further comprising handrail means.

* *.* *1 * S
10. Formwork as claimed in claim 9, wherein the formwork is provided with socket *5** *S * . * ** means to receive the handrail means, mounted directly to the formwork. * .. * a * Ut
11. Formwork as claimed in any one of the preceding claims, comprising means to secure the formwork to an underlying ground surface.
12. Formwork as claimed in claim 11, wherein the means to secure the formwork comprises apertures in each formwork unit, adapted for elongate anchoring members to be passed therethrough into the underlying ground.
13. Formwork as claimed in any one of the preceding claims, comprising a plastics material, optionally a recycled plastics material.
14. Formwork for the construction of a flight of steps on a sloping surface, substantially as described herein with reference to the Figures of the accompanying drawings.
15. A flight of steps comprising a formwork as claimed in any one of the preceding claims.
16. A method of constructing a flight of steps on a sloping surface, comprising the method steps of providing formwork as claimed in any one of the preceding claims, assembling said formwork on the sloping surface, filling said formwork with a constructional filler material, and mounting paving means on an upper surface of *sss the constructional filler material.

*s.. .4 * :
17. A method of constructing a flight of steps on a sloping surface as claimed in claim *: : :* 16, comprising the firther method step of preparing the sloping surface by grading it appropriately to receive the stair formwork units and landing formwork units of the formwork.
18. A method of constructing a flight of steps on a sloping surface as claimed in either claim 16 or claim 17, comprising the further method step of locating reinforcement means for the constructional filler material in or under the formwork prior to filling with the constructional filler material.
19. A method of constructing a flight of steps on a sloping surfaee as claimed in any one of claims 16 to 18, wherein the constructional filler material comprises concrete.
20. A method of constructing a flight of steps on a sloping surface as claimed in any one of claims 16 to 19, comprising the further method step of mounting handrail means for the flight of steps directly to the formwork.
21. A method of constructing a flight of steps on a sloping surface, substantially as described herein and with reference to the Figures of the accompanying drawings. S. St * S * S* S.... * S00*q.S * S *5 * SO * * * S. S.. S * 54