GB2464993A

GB2464993A - Former for plastering around light switches, sockets and telephone point apertures

Info

Publication number: GB2464993A
Application number: GB0820166A
Authority: GB
Inventors: James Cunningham
Original assignee: Socket Solutions Ltd
Current assignee: JAMES CUNNINGHAM
Priority date: 2008-11-04
Filing date: 2008-11-04
Publication date: 2010-05-05
Also published as: GB0820166D0

Abstract

The invention relates to a former 10,50 for use in applying a skim coat of plaster to a substrate (40 figure 3) having an opening (41 figure 3). The former comprises a substantially planar base sheet 12 having an aperture 11 of the required finished size for the opening in the substrate. The base sheet is adapted for mounting on the surface of the substrate with the aperture in register with the substrate opening. The former also comprises a flange 20 upstanding from the base sheet around the aperture to provide a finished edge to the aperture. To use the former the base sheet is mounted on the substrate and the skim coat is applied over the substrate and base sheet, and is finished up to the flange of the former. The former may also include an adhesive layer 30 on the base sheet by which it may be secured to the substrate 40. Alternatively holes 23, 24 may be used to screw the former to the substrate.

Description

FORMER

The present invention relates to a former for use in forming an aperture in a skim-coated waU.

The finishing of internal was of budings has evolved considerably over the years with the development of new materials and techniques. The drive for such S evolution has been spurred by the competitive nature of the building industry which requires the finishing to be formed quickly and inexpensively while having a smooth appearance.

Traditionally, plastering was the preferred method of finishing an internal wall, which includes applying a rendering layer to a masonry wall, then a second layer known as a floating layer and then a third layer known as a skim layer. Since each layer must dry before a subsequent layer may be applied this technique can delay the completion of a building and is nowadays less common. Preferred techniques include the use of plasterboards which typically comprise gypsum sandwiched between two sheets of heavy paper, though other materials can be included where specific properties are required. One of those techniques involves mounting battens to a masonry wall and fastening the plasterboards to the battens by nails or screws or by applying dabs of plaster adhesive to the masonry wall and presenting the plasterboards to the dabs. A skim coat of plaster can be applied to the entire surface. A second technique known as dry lining requires dabs of plaster adhesive to be applied to the masonry wall and the plasterboards to be presented to the dabs and then carefully levelled so that they all lie in a common plane. A tape is then applied over the joints and covered with a sealant.

Due to the significant saving in time associated with the use of plasterboards compared to plaster layers, the techniques using plasterboards are preferred. Generally, the finish achieved by skimming the plasterboards is considered to be superior to the finish achieved with dry lining, as it is difficult properly to level the plasterboards and to hide the taped joints.

Achieving a superior finish is not always straightforward as defects often arise around wall-mounted fittings. Specifically, most wall mounted e'ectrical fitting such as light switches, plug sockets, telephone points and so forth include a housing disposed within an opening formed in the plasterboard, a cable trailing behind the plasterboard and entered into the housing and a facia that mounts to the front of the plasterboard and fastens to the housing. Though the skim coat is app'ied to the plasterboards prior to installation of the facia, it is difficult to achieve a neat finish around the opening, and even when such a finish is achieved it is often chipped or cracked prior to or during installation of the facia by an electrician.

This then requires a plasterer to repair the plaster around the opening, a painter to paint over the repaired plaster and the e'ectrician to reattempt to install the facia, which delays the completion of the building significantly and incurs additional costs.

A principal object of this invention is to overcome the problems associated with applying a skim coat of plaster around openings in plasterboards while maintaining the appearance of skim-coated walls.

According to the invention, there is provided a former for use in applying a skim coat to a substrate having an opening therein, which former comprises: -a substantially p'anar base sheet having an aperture therein of the required finished size for the opening in the substrate, the base sheet being adapted for mounting on the surface of the substrate with the aperture In register with the substrate opening; and -a flange upstanding from the base sheet around the aperture therein; whereby In use the base sheet is mounted on the substrate with the flange dIrected away therefrom and the skim coat is applied over the substrate and base sheet and is finished to the flange of the fomw.

In a preferred arrangement, holes are provided In the base sheet to enable the skim coat applied to the base to key with the substrate. The plaster is likely to form a stronger bond with the plasterboard than it would with the base, which, in combinatIon with the keying effect Is likely to provide a better finish arid prevent movement of the base. The holes may be of any size and shape and may even define letters and numbers.

Advantageously the base sheet may have a non-rectilinear outer peripheral edge. For example, the outer peripheral edge may be undulating, or provided with saw teeth that also serve to form an improved bond between the plaster, base and plasterboard. The general shape of the base may also vary such that the width of the base around the square aperture may be non-uniform, particularly If it is to fit in an obscure space such as a narrow space between two adjacent doorframes. For Instance the base may comprise discreet portions extending outwardly from the flange. The material from which the former is made may be such that the base canbet,Immedbysdssorsoraknife,bellertosultthespaceinwhichitistobe fitted. Most preferably the former is made from a thin plastics material which is relatively Inexpensive and can be easily manufactured and manipulated.

Furthermore the flange may have a free edge that iies in a plane parallel to the base sheet. This is preferable to ensure that the skim coat of plaster + surrounding the square aperture and an electrical fitting mourned over the aperture lie in planes parallel to the plane of the substrate.

Preferably, an adhesive layer is provided on the rear face of the base sheet so as to adhere the former to the substrate. Most preferably the adhesive layer Is covered by a backing sheet which can easily be removed immediately before use to reveal the adhesive layer.

Advantageously, at least one projection may extend Inwardly Into the aperture In the plane thereof and which may be provided with a hole so that In use a screw may be passed through the hole and be threaded into a housing provided In the substrate opening. For Instance, most wall mountable electrical fittings comprise a housing to be disposed within the opening In the substrate and a facla to be fitted to the housing. Generally, such housings comply with standards laid down for such fittings and have threaded holes for receMng screws passing through the fasclas. The holes provided on the projectiors may also be approprIately sized and positIoned so as to align with said holes In the housing.

Most preferably, the former iMudes two projections provided on opposed sides of the flange. The hole In at least one of the projections Is preferably elongate so as enable the angular position of the former relative to the housing to be adjusted, which is particularly advantageous when the housing is not squarely mounted to the wall. Alternatively or additionally, the position of at least one of the projections may be adjustable to compensate for any angular misalignment between the former and the housing.

The aperture in the former may take any size to suit its purpose. The former is particularly well suited for forming apertures in skim coated wails where electrical fittings are to be mounted and such fittings usually include a square or rectangular housing and a square or rectangular fascia. in view of this the aperture in the former may also be square or rectangular.

In an alternative arrangement, there is provided on the rear face of the base sheet a housing sized to fit In the substrate opening and accessible through the aperture. Thus, an electrical fitting mounted to the skim coat may have a body that locates through the aperture and into the housing where it may connect to an electrical cable.

According to the invention there is also provided a method of forming an aperture of a required size in a substrate, comprising the steps of: -providing an opening in the substrate at least as large as the aperture to be formed; -mounting a former as claimed In any preceding claim to the substrate so that the former aperture registers with the opening.

-applying a skim coat to the substrate and base sheet and finishing the skim coat to the flange of the former.

Preferably that method may also include the step of adhering the rear face of the base sheet to the substrate as this will serve to secure the former in position, which Is particularly Important prior to and during the application of the 51dm coat.

in addition or as an alternative to the previous step, the method may also Include the step of fixing the former to a housing disposed within the substrate opening. This is particularly advantageous as this will assist in ensuring that the former is appropriately aligned with the housing.

Two embodiments of the Invention wILL now be described In detail, with reference being made to the accompanying drawings, in which Figure 1 is a front perspective view of a first embodiment of the invention; Figure 2 is a rear perspective view of the first embodiment of the invention; Figure 3 is a sectional view of the first embodiment of the invention taken atong the Line AA shown in Figure 1 and mounted to a watt; Figure 4 is a front perspective view of a second embodiment of the invention; Figure 5 is a rear perspective view of the second embodiment of the invention; and Figure 6 is a sectionaL view of the second embodiment of the invention, taken along the tine BB shown in Figure 4 and mounted to a walL Referring initially to Figures 1 and 2, there is shown a former generally indicated 10, to assist in the proper formation of a square aperture 11 in a skim coated watt. The former 10 comprises a square planar base 12 made from a thin plastics material approximately 1mm thick and having opposed front and rear faces 13, 14 and an outer peripheral face 15. A large square aperture 11 is provided in the centre of the base 12 and a plurality of small square hoLes 17 are formed through the base 12 around the large square aperture 11. The size and shape of the small holes 17 may vary and they may even include letters or numbers to spell a word such as the manufacturer's brand.

An upstanding flange 20 provided on the front face 13 extends around the square aperture 11 and has an interior waLl 21 that is co-extensive with the inner peripheral wall surrounding the aperture 11. The flange 20 has a front edge 22 which lies in a plane parallel to the rear face 14 and is spaced approximately 3mm from the front face 13.

Extending inwardly from two opposed walls of the inner peripheral face defining the aperture is a pair of tabs 23,24 coplanar to the base 12. Tab 23 has S a circular hole 25 formed therein and tab 24 is slightly larger and has an elongate hole 26 formed therein. The purpose of the tabs 23,24 will be described in more detail below.

An adhesive layer 30 is provided on the rear face 14 of the base 12 and a backing (not shown), which is to be peeled off before use, protects that layer.

Referring now to Figure 3, a wall 35 to which the skim coat is to be applied should first be properly constructed prior to using the former 10. This includes mounting a housing 36 of an electrical fitting to the block or brick work 37 and feeding the appropriate electrical cables 38 into said housing.

Plasterboard or like substrate 40 having an opening 41 at least as large as the square aperture 11 should be presented to the block work 37 so that the opening 41 aligns with the housing 36. The plasterboard is then secured to noggings 39 already provided on the block work 37 by adhesive or fasteners.

The backing sheet is peeled away from the rear face 14 to reveal the adhesive layer 30 and the former 10 is then presented to the waLl. 35, such that the square aperture 11 registers with the opening 41 and the flange 20 is orientated appropriately, preferably having its sides running horizontally and vertically. If, for example, the adhesive is not bonding well with the plasterboard 40, the former 10 can be held in place by fastening screws through the holes 25,26 and into threaded holes (not shown) formed in the housing 36.

Elongate hole 26 allows for any angular misalignment between the housing and the intended position of the former, by enabling the position of the screw passing through that hole to be varied relative to the position of the screw passing through hole 25. A skim coat 42 of plaster is then applied to the plasterboard 40 and to the base 12 up to the level of the flange 20. The skim coat penetrates the holes 17 such that some of the plaster applied to the base 12 bonds to the plasterboard 40.

A second embodiment of the invention is shown in Figures 4 to 6, though features common to both embodiments have been given the same reference numbers. Figures 4 and 5 show a former 50 having a base 12 with a square aperture 11 formed therethrough and a flange 20 upstanding from the front face 13 of the base and extending around the square aperture. Provided on the rear face 14 of the base is a housing 51 having a square rear plate 52 located behind the square aperture 11 and four side walls 53 disposed between the rear plate 52 and base 12 which are coplanar to the four waLls of the flange 20. Two holes 54 are formed in the rear plate 52 of the housing 51 and by which the former 50 can be secured to a wall therebehind by screws 56. The housing 51 is also provided with several other holes (not shown) through which power cables or data cables 38 can enter the housing 51. A pair of tabs 57,58 are provided on opposed side walls 53 of the housing and each has a threaded hole 55,59 formed therethrough such that an electrical fitting mounted over the square aperture 11 can be fastened in place by screws threadingly engaging those holes. Hole 59 is elongate so as to allow for any angular misalignment between the former and the electrical fitting. This reduces the necessity for the workman installing the former to ensure that the angular position of the housing is perfect, which is often difficult to achieve when the flooring and plasterboards are not yet completed.

Referring now to Figure 6, an opening 41 may be formed in the plasterboard 40 prior to being mounted to noggings 39. The backing is removed from the adhesive layer 30 and the former 50 is then presented to the plasterboard 40 such that the housing 51 extends through the opening 41. The plasterboard 40 and former 50 are then offered to the block work 37 and any cables 38 fed into the housing 51 prior to the plasterboard being permanently secured in place.

Atternativety, the plasterboard 40 may be secured to the noggings 39 prior to mounting the former 50 in the opening 41, but difficulties may arise in attempting to feed any cables 38 trailing between the plasterboard and block work into the housing, once the plasterboard is already in pLace.

Claims

CLAtMS 1. A former for use in applying a skim coat to a substrate having an opening therein, which former comprises: -a substantay planar base sheet having an aperture therein of the required finished size for the opening in the substrate, the base sheet being adapted for mounting on the surface of the substrate with the aperture in register with the substrate opening; and -a flange upstanding from the base sheet around the aperture therein; whereby in use the base sheet is mounted on the substrate with the flange directed away therefrom and the skim coat is applied over the substrate and base sheet and is flnshed to the flange of the former.
2. A former as claimed in claim 1, wherein holes are provided in the base sheet to enable the skim coat to key with the substrate.
3. A former as claimed in claim 1 or claim 2, wherein the base sheet has an undulating outer peripheral edge.
4. A former as claimed in any preceding claim, wherein the flange has a free edge that lies in a plane parallel to the base sheet.6. A former as claimed in any preceding claim, wherein an adhesive layer is provided on the rear face of the base sheet for securing the former to the substrate.7. A former as claimed in any preceding claim, wherein there is at least one projection extending inwardly into the aperture in the plane thereof and which is provided with a hole so that in use a screw may be passed through the hole and be threaded into a housing provided in the substrate opening.t A former as claimed in claim 7, wherein there are two projections provided on opposed sides of the flange.9. Aforrnerasclaimedinanyprecedingciaim,wherstheapertureis rectangular.10. A former as claimed in any preceding claim, wherein the former is made of plastics material.ii. A former as claimed In any preceding claim, wherein a housing Is provided on the rear face of the base sheet behind the aperture and sized to fit in the opening, the housing being accessible through the aperture and being adapted for use with an electilcai fitting mountable over the aperture.12. A former as claimed in claim 1 and substantially as hereinbefore before described with reference to and as iiiustrated in the accompany drawings.13. Amethodofformlnganapertureofarequlredslzelnasubstrate, comprising the steps of: -providing an opening in the substrate at least as iarge as the aperture to be formed; -mounting a former as claimed in any preceding claim to the substrate so that the former aperture registers with the opening.-applying a skim coat to the substrate and base sheet and finIshing the sklmcoattotheflangeoftheformer.14. Amethodasciaimedinciaiml3,andfurtherinciudlngthestepofadhering the rear face of the base sheet to the substrate.15. A method as claimed in claIm 13 and claim 14 when dependent on any of claims 1 to 10, andfurthercompilsingthestepofflxlngtheformertoahousing dIsposed within the substrate opening.16. A method of forming an aperture of a required size in a substrate as c'aimed in c'aim 13 and substantiay as hereinbefore described with reference to and as iUustrated in the accompanying drawings.