GB2303862A - A ceiling and a method of constructing the same - Google Patents

Abstract

A ceiling construction including a layer of plasterboard sheeting 12 having a lower face 14 and an upper face 16, a plurality of spaced-apart metal profile beams 18 attached by screws 24 to the upper face of the plasterboard sheeting, at least one layer of steel reinforcing elements 26 positioned above the metal profile beams, and a layer of concrete 20 unifying the plasterboard sheeting, the metal profile beams and the reinforcing elements. A method for the construction of the ceiling is also provided, in which the plasterboard 12 with beams 18 and reinforcement 26 already attached is laid on temporary shuttering, and the concrete is then poured to form the composite structure.

Description

A CEILING AND A METHOD OF CONSTRUCTING THE SAME Background of the Invention The present invention relates to a ceiling and a method for its construction.

More particularly, the invention provides a method and means for the fast and efficient erection of a ceiling which is provided, on its lower face, with a finished smooth surface to the standards prevalent for residential use.

The conventional method of obtaining a smooth ceiling surface is by the application of liquid plaster by trowel. This method is labor-intensive, messy, and requires workers skilled in the preparation and smooth application of the plaster.

High quality plastering requires at least two, preferably three, layers, and the plaster composition differs for the various layers. Low quality plaster, when dry, is brittle and liable to crack as a result of minor earth tremors or differential settlement of the building foundation.

The high costs incurred in liquid plastering may be avoided by the use of gypsum board, also known as plasterboard. The board is typically 12.5 mm thick, and the brittle interior is protected from damage by an attached sheet of carton on each outer face. Such boards are produced today in massive quantities.

In Israel today, the most widely practiced method of ceiling construction is to cast a reinforced concrete slab to meet structural requirements, then to add a light steel framework under the slab, and attach plasterboard panels under the framework. The framework takes up a height of 10 to 12 cm. Acoustic andlor thermal insulation can be inserted into this space, as well as service conduits.

Architects favoring the above-described type of construction may not have given sufficient consideration to the resulting costs. In order to maintain the required inner dimensions, the outer height of the building must be increased by 10 cm per floor. In a ten-storey building, an extra meter of height is thus added to the outer walls, pillars, stairs, elevator and service conduits; the cost of such additions is far from negligible.

A further type of construction also in use today, though to a much lesser extent, involves the casting of a reinforced ceiling slab, followed by the application of a coating of adhesive filler material to the lower face of the slab and the attachment thereto of plasterboard. The system is expensive, as large quantities of filler material are often required and the method presents difficulties in obtaining a level, flat ceiling surface.

Israel Patent 96237 describes and claims a reinforced concrete slab structure comprising lowermost plate components in abutting relationship, essentially comprising inserts in the body of the concrete. The inserts are adhesively connected to the plate components. Preferred plates are made of gypsum, and the preferred inserts used are made of foamed plastics. As can be appreciated, there are well-known difficulties in obtaining reliable adhesive bonds on surfaces which are not clean and dry, conditions unlikely to prevail at building or industrial sites. In practice, it has been found that the adhesive bond does suffer from delamination, and repairs to such ceilings have to be made at a later stage.

The present invention is intended to obviate the disadvantages of prior art ceiling construction, and to provide a ceiling which is compact, has the low cost associated with the use of plasterboard, and wherein said plasterboard is reliably attached.

Summary of the Invention The present invention achieves the above objectives by providing a ceiling construction comprising a layer of plasterboard sheeting having a lower face and an upper face; a plurality of spaced-apart metal profile beams attached, by means of screws, to said upper face of said plasterboard sheeting; at least one layer of steel reinforcing elements positioned above said metal profile beams, and a layer of concrete unifying said plasterboard sheeting, said metal profile beams and said reinforcing elements.

According to a preferred embodiment of the present invention, there is no need to cover the screw heads with filler material. The screw heads do not project from the lower surface of the plasterboard, since the screws are inserted through, and abut, the profiled beams which are attached to the upper face of the plasterboard.

It will thus be realized that, in contradistinction to the ceiling and construction described in Israel Patent 96237, the present invention provides a secure, reliable method of attaching the plasterboard to the ceiling. Screwing, unlike the preparation of adhesive joints, can be carried out under less than ideal conditions of cleanliness. Furthermore, the long-term reliability of screws far exceeds that of adhesives; screwing also avoids the flammability hazards associated with acrylic adhesives during application.

It is a further object of the present invention to provide an efficient, timesaving method of ceiling construction. Accordingly, the invention provides an efficient method for the construction of a ceiling, comprising the steps of: (a) providing plasterboard sheeting having an upper face and a lower face; (b) attaching a plurality of metal profile beams to the upper face of said plasterboard sheeting by means of screws; (c) laying said plasterboard sheeting on preerected form boards, with the attached metal profile beams facing upwards; (d) laying steel reinforcing elements on said metal profile beams; (e) pouring concrete to unify said plasterboard sheeting, said metal profile beams and said reinforcing elements; and (f) removing said form boards.

Brief Description of the Drawings The invention will now be described in connection with certain preferred embodiments with reference to the following illustrative figures so that it may be more fully understood.

With specific reference now to the figures in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

In the drawings: Fig. 1 is a fragmented, perspective view of the layers of a preferred embodiment of the ceiling construction according to the invention; Fig. 2 is a side view of an embodiment of the invention wherein the screw heads do not mar the lower surface of the ceiling; Fig. 2A is an enlarged view of a portion of the embodiment of Fig. 2; Fig. 3 is a detailed view of an embodiment showing filled gaps between plasterboard edges; Fig. 4 is a detailed view of a further method of filling gaps between plasterboard edges; and Fig. 5 is a side view of the embodiment shown in Fig. 1, under construction.

Detailed Description There is seen in Fig. 1 a height-saving ceiling construction 10. A layer of plasterboard sheeting 12, having a lower face 14 and an upper face 16, provides the smooth surface required for residential ceilings. A plurality of spaced-apart metal profile beams 18 contacts upper face 16. Beams 18 are required only to support the plasterboard sheeting 12 and therefore thin, rolled-section steel, under 1 mm thick, is adequate. Beams 18, in almost any desired profile, are easily produced by cold roll forming. As beams 18 are eventually embedded in concrete 20, they require little or no corrosion protection.

Beams 18 are attached by means of screws 22 to the upper face 16 of plasterboard sheeting 12. In the embodiment of Fig. 1, the screw heads 24 abut the plasterboard lower face 14, and are covered with a filler material (not shown) during finishing operations. A layer of steel reinforcing elements 26 is positioned above the metal profile beams 18 to meet structural requirements. The reinforcing elements 26, typically round rods with surface deformations to improve adhesion to the concrete 20, are of the conventional type.

A layer of concrete 20 unifies the plasterboard sheeting 12, the metal profile beams 18 and the reinforcing elements 26. As is known, steel reinforcing elements must be covered by at least 2 cm of concrete for fire resistance and corrosion protection. Such cover is obtained in the present invention due to the reinforcing elements 26 resting on metal profile beams 18, the concrete 20 thereafter penetrating between these beams. Concrete 20 thus substantially covers the entire space between the metal profile beams 18 and plasterboard sheets 12, and ban be used at a thinner total thickness. As the plasterboard sheeting 12 is in direct contact with concrete 20, the overall thickness of ceiling 10 is the minimum possible to meet load-carrying requirmeents.

Referring now to Fig. 2, similar numerals are used for identifying similar parts. There is shown a ceiling construction 28, similar to that described above with reference to Fig. 1; however, the plasterboard sheeting 12 is screwed to metal profile beams shaped as U-channels 30. A first, lower leg 32 of the channel is screwed to the plasterboard, an opposite, second leg 34 is substantially parallel thereto, and the connecting web 36 is exposed, on both of its sides, to allow contact with the layer of concrete 20. As is seen more clearly in Fig. 2A, screws 22 are advantageously inserted through the channels 30, the screw heads 24 abutting the first, lower leg 32. The opposite, second leg 34 is shorter than the lower leg, to provide convenient access for the screwdriver (not shown).For providing even more convenient access to the screwdriver, beams having a Z profile, such as beams 38 in Fig. 2, may also be used. Insertion of the screws 22 into the plasterboard sheeting 12 from the upper face, after they pass through the metal profile beams 30 or 38, is advantageous in eliminating any projection of the screw heads on the lower face 14 of the plasterboard sheeting, thus saving finishing operations.

Fig. 3 illustrates a detail of a ceiling construction 40, wherein adjacent edges 42 of plasterboard sheets 44 are chamfered and closed by filler material 46. Filler material 46 thus forms a continuous bear and supports other filler material which has penetrated into any spaces between the plasterboard sheets 44.

There is seen in Fig. 4 a detail of an embodiment 48, which is similar to that shown in Fig. 3. In this embodiment, however, adjacent chamfered edges 50 of the plasterboard sheeting 52 are closed by adhesive tape 54. The chamfer eliminates projection of the thickness of the tape below the lower face 56 of plasterboard sheeting 52. Filler material 58 is applied as required, to finish face 56.

Fig. 5 depicts ceiling 10, described above with reference to Fig. 1, during the course of construction, which is carried out by the following method: Plasterboard sheeting 12 is provided, having an upper face 16 and a lower face 14. A plurality of metal profile beams 18 are attached to the upper face 16, using self-piercing, self-drilling and self-tapping screws 22, which require no predrilled holes and can be driven in and assembled within a few seconds with a suitable power tool. The plasterboard sheeting 12 is placed in abutting relationship on supporting form boards 60, which are set up at a predetermined height from the floor. Sheeting 12 is placed on the boards 60 with the attached metal profile beams 18 facing upwards. Steel reinforcing elements 26 are then laid on the metal profile beams 18. If desired, the reinforcing elements 26 may be attached to beams 18.At this stage, and prior to the pouring of concrete 20, it is desirable to also place service conduits 64, such as electric and communication cable conduits, water and drainage pipes, air conditioning ducts, etc. Concrete 20 is then poured to unify the plasterboard sheeting 12, the metal profile beams 18 and the reinforcing elements 26. The form boards 60 are eventually removed after the setting of the concrete.

In order to obtain a good finish in preparation for painting, filler material 46 is applied into gaps between adjacent plasterboard sheets 12. A further preferred finishing step is the application of adhesive tape 54, either by itself or in combination with plaster, to cover gaps between adjacent plasterboard sheets 12.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrated embodiments and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (10)

WHAT IS CLAIMED IS:

1. A ceiling construction, comprising: a layer of plasterboard sheeting having a lower face and an upper face; a plurality of spaced-apart metal profile beams attached, by means of screws, to said upper face of said plasterboard sheeting; at least one layer of steel reinforcing elements positioned above said metal profile beams, and a layer of concrete unifying said plasterboard sheeting, said metal profile beams and said reinforcing elements.

2. The ceiling construction as claimed in claim 1, wherein said metal profile beams are U channels, a first leg of each of said U channels being screwed to said plasterboard, an opposite, second leg and the web being exposed on both sides to allow contact with said layer of concrete.

3. The ceiling construction as claimed in claim 1, wherein said screws are inserted through said metal profile beams, the screw heads abutting a surface thereof.

4. The ceiling construction as claimed in claim 1, wherein adjacent edges of said plasterboard are chamfered and closed by a filler material.

5. The ceiling construction as claimed in claim 1, wherein adjacent edges of said plasterboard are chamfered and closed by adhesive tape.

6. A method for the construction of a ceiling, comprising the steps of: (a) providing plasterboard sheeting having an upper face and a lower face; (b) attaching a plurality of metal profile beams to the upper face of said plasterboard sheeting by means of screws; (c) laying said plasterboard sheeting on preerected form boards, with the attached metal profile beams facing upwards; (d) laying steel reinforcing elements on said metal profile beams; (e) pouring concrete to unify said plasterboard sheeting, said metal profile beams and said reinforcing elements; and (f) removing said form boards.

7. The method as claimed in claim 6, further comprising the step of attaching said reinforcing elements to said metal profile beams.

8. The method as claimed in claim 6, further comprising the step of applying filler material into gaps between adjacent plasterboard sheets.

9. The method as claimed in claim 6, futher comprising the step of applying adhesive tape to cover gaps between adjacent plasterboard sheets.

10. The method as claimed in claim 6, further comprising the step of laying service conduits prior to the pouring of said concrete.