GB2078277A - Roof - Google Patents

Abstract

The roof is constructed of hollow glass-reinforced-plastics (GRP) sections, each comprising upper and lower members connected or spaced apart by web(s). The sections may be preformed, one side of each being open and the other side being in the form of a web to engage the said open side of an adjacent section, or each section may be made up of separate upper and lower members spaced apart by web low member(s). The roof may abut a wall. Members or webs may be of rigid foam sandwiched between GRP. A coat of GRP may be applied to the roof after assembly, and/or a coat of resin without glass, e.g. coloured resin, may be applied. Glass-fibre matting may be applied underneath the roof to enable plaster to adhere. <IMAGE>

Description

SPECIFICATION Improvements in or Relating to the Construction of Roofs This invention relates to a method of roof construction and to roofing elements for use therein.

An object of the invention is to provide a method of roof construction, which involves the use of glass reinforcement plastic (GRP), at a cost comparable with the conventional type of roof made of timber covered with bitumen felt.

It is also an object of the invention to provide a roof the elements of which can easily be transported and assembled on site.

According to the invention, a roof comprises a plurality of hollow sections made of glass reinforced plastic (GRP), each section comprising upper and lower members connected or spaced apart by one or more webs.

According to one embodiment, the sections are preformed, one side of each section being open and the other side of the section being in the form of a web adapted to engage in the open side of the adjacent section. As many sections as may be necessary to form a roof the required width are assembled in this way.

The width of the sections may correspond with the normal spacing of timber beams (about 0.3 metre). Thus, for example, a roof 5 metresx6 metres would consist of 20 sections (0.3 x20=6) of metres span. Each such section would weight about 1 5 kg and is thus easily transportable.

According to a further feature of the invention, a plastic resin adhesive may be applied to the joints between the sections to render them watertight.

According to another embodiment each section is made up of separate upper and lower members spaced apart by one or more web members secured to the upper and lower members to form a rigid structure.

The upper members may have a sandwich construction consisting of rigid foam, for example polyurethane, between laminations ofgrp, thus enabling the webs to be spaced farther apart since the sandwich construction has considerable rigidity. The webs may also be of sandwich construction or corrugated for increased stiffness.

The sandwich construction also provides heat insulation.

A further advantage of this embodiment is that the edges, such as drips or raised edges, can be incorporated in the sections and the top and bottom surfaces can be differently coloured and finished.

Yet another advantage of this embodiment is that sections one metre or more in width can be prefabricated and still be light enough to handle easily on site. If woven rovings are used instead of random fibres, a 5 metre span 1 metre wide would weigh only about 30 kg, easily handled by two men. For shorter spans, proportionally greater widths could be used.

According to yet another feature of the invention, a final coat of GRP may be applied to the outer surface of the roof after assembly to give even greater resistance to water penetration.

Such final coating may advantageously be applied for a short distance up any abutting walls to prevent leakage at such points. Any pipes that need to pass through the roof can be similarly sealed into the roof.

According to a still further feature of the invention, the roof may be given a final coat of resin without glass fibre to avoid reduction of water resistance by exposed fibres. Said final coat of resin could be coloured or have chippings applied to it before it sets, for decorative effect.

The underside of the roof could be covered by a decorative coat of coloured resin. Alternatively, glass fibre matting that is not fully saturated could be applied to said underside which should allow plaster to adhere thereto.

Forms of GRP are available having resistance to the spread of flames and these would be used to comply with various building regulations.

During the assembly of the roof, rock-wool or similar matter can be inserted in each section to provide heat insulation.

The invention will now be described by way of example with reference to the accompanying drawings, wherein: Figure 1 illustrates the method of forming a roof using one form of preformed section, Figure 2 illustrates the method of forming a roof using sections made up of separate upper and lower members connected by webs.

Figures 3 and 4 illustrate two forms of joint between the sections of Figure 2, Figure 5 illustrates a form of section for use in a free-standing roof, and Figure 6 illustrates a form of section for use in a roof that abuts a wall.

Referring first to Figure 1, a roof is made up of a plurality of longitudinal sections 10 each having a top wall 11 and a bottom wall 12, said walls being connected by a web 13. The web 13 is of slightly less height than the main body of the section so that it may make a sliding fit within the open end of the adjacent section.

Referring now to Figures 2 to 6, the roof is formed from a plurality of sections, each section being made up of an upper member 14 and a lower member 1 5 spaced apart by webs 1 6. Both the upper members 14 and the webs 1 6 are of sandwich construction comprising a layer of rigid foam 1 7 between layers 1 8 of glass reinforced plastic. The lower members 1 5 consist of layers of glass reinforced plastic.

One form of joint between the sections is illustrated in detail in Figure 3. The upper layer 1 8 of the upper member 14 is formed at one end with a step 19 leading to a channel 20 for draining away any leakage of water through the joint, and at the other end with a lip 21 which overlaps the step 19 and channel 20. The sections are connected together by means of rivets 22 passed through the lip 21, member 14 and web 1 6. A bonding layer of GRP 23 is incorporated between members 14 and web 1 6 to make the web 16 and upper member 14 an integral structure. A sealing compound 30 is applied between the step 19 and the lip 21.

A ridge form of joint is illustrated in Figure 4.

The opposite sides of the upper layer 1 8 of the upper member 14 are formed with engaging inverted channel members 24 which form a barrier against any leakage of water Figure 5 illustrates a section for use in forming a free-standing roof and formed at one end with a drip 25 and at the other end with a raised edge 26 and a drip 27.

Figure 6 illustrates a section for use in forming a roof that abuts a wall, for example. In this case, the section is formed with a drip 28 at one end and a wall seal 29 at the other. It has been found that by using sections according to the invention wherein the top and bottom walls are integrally connected by the webs, it is possible to construct a roof of adequate strength at a cost comparable to that of a conventional timber roof, with the advantage that the roof may be easily and quickly constructed from prefabricated elements that are easily transported and handled.

The method of roof construction according to the invention is particularly suitable for the construction of flat roofs but is not to be regarded as limited thereto.

Claims (12)

Claims

1. A roof comprising a plurality of hollow sections made of glass reinforced plastic, each section comprising upper and lower members connected or spaced apart by one or more webs.

2. A roof according to claim 1, wherein the sections arepreformed, one side of each section being open and the other side of the section being in the form of a web to engage in the open side of the adjacent section.

3. A roof according to claim 1, wherein each section is made up of separate upper and lower members spaced apart by one or more web members securedho the upper and lower members to form a rigid structure.

4. A roof according to claim 3, wherein the upper members of the sections are of a sandwich construction consisting of rigid foam between layers of glass reinforced plastic.

5. A roof according to claim 3 or 4, wherein the web members are of a sandwich construction consisting of rigid foam between layers of reinforced plastic.

6. A roof according to any of claims 3 to 5, wherein the upper members of the sections are formed with a channel member at one end thereof to form a drain and with a lip at the other end thereof which overlies said drain.

7. A roof according to any of claims 3 to 5, wherein the opposite sides of the upper members of the sections are formed with engaging inverted channel members to form a seal.

8. A roof according to any of the preceding claims, wherein a final coat of GRP has been applied to the outer surface of the roof after assembly.

9. A roof according to any of the preceding claims, wherein a final coat of resin without glass has been applied thereto.

10. A roof according to any of the preceding claims, wherein the underside of the roof has been covered by a decorative coat of coloured resin.

11. A roof according to any of claims 1-9, wherein glass fibre matting that is not fully saturated has been applied to the underside of the roof.

12. A roof substantially as hereinbefore described with reference to the accompanying drawings.