GB2265919A - Glazed roof for e.g. conservatory - Google Patents

Abstract

A glazed roofing system comprises spars (12a, 12b) profiled for glazing and fabricated from steel or other material of like rigidity and rigidly connected together at the or an apex of the roofing system or formed integrally as an angled beam, whereby substantially to avoid any sagging or spreading of the lower edges of the system without the need to introduce tie bars or other additional internal support. The spars may be of plastics-coated steel. <IMAGE>

Description

ROOF SPAR ARRANGEMENT This invention concerns a roof spar arrangement, particularly, though by no means exclusively, for use in roofs comprising glass, for example, in conservatories and greenhouses.

Conventional glass roof systems for conservatories and greenhouses are made up from separate spars which meet at and are connected to a ridge, making a joint at the top of the roof and thereby creating a weak spot which may allow movement of the individual spars. This movement generally causes the roof to sink down onto the walls of the conservatory or greenhouse forcing them to bow outward. Reinforcement of roof systems is possible using tie bars to prevent this movement, but this is not a practical solution for conservatories and greenhouses since the roofs tend to be too low for such reinforcement, ie. just above head height and, additionally, such tie bars would not be aesthetically pleasing.

The present invention provides a roof spar arrangement which overcomes, at least to some extent, the problems aforesaid.

According to the present invention there is provided a glazed roofing system comprising spars profiled for glazing and fabricated from steel or other material of like rigidity and rigidly connected together at the or an apex of the roofing system whereby substantially to avoid any sagging or spreading of the lower edges of the system without the need to introduce tie bars or other additional internal support.

A simple pitched roof may be provided by inverted V-members of rigid spars rigidly joined together as by welding or bolting. Having such rigidity as to have substantially no tendency to sag or spread, they do not apply spreading forces to the uprights on which they are supported. The same applies to a more complicated pitched roof design having a flat central section. Here, three rigid spars can be rigidly joined together.

Simply making the spars in steel of the same cross section as conventional aluminium spars gives sufficient rigidity provided that they are rigidly joined together as by welding or bolting against angular displacement.

Since it is difficult to source steel spars which are profiled for glazing, the invention also provides an outer sheath of e.g. extruded plastics material which not only affords the requisite profiles but also provides an aesthetic cover for the steel and hides welds or bolts.

A small gusset plate or bracket can be used to reinforce the welded, bolted or otherwise connected joints.

The roof frame members can be prefabricated for ease of construction.

It is known to reinforce plastic glazing extrusions with steel sections, but not to join them together rigidly against angular displacement for the purposes herein set forth. It is also known to use steel internal supporting or reinforcing frames within glazed structures, the glazing system however being separate. Such additional support or reinforcement, which is obtrusive, is unnecessary with the system of the present invention.

The roof spars may be connected to the wall frame of a building such as a conservatory or greenhouse by rigid brackets These brackets act to transform any inwardly directed forces which may be exerted onto the wall frame by the rigid roof spars, into downwardly directed forces thus preventing any lateral movement of the wall frame.

The invention will be further apparent from the following description, with reference to the several figures of the accompanying drawings, which show,by way of example only, a number of forms of the roof spar arrangement embodying same.

Of the drawings : Figure 1 shows the roof spar arrangement connected to the wall frame of a building by brackets; Figure 2 shows a first embodiment of the roof spar arrangement; Figure 3 shows a second embodiment of the roof spar arrangement; Figure 4 shows a third embodiment of the roof spar arrangement; Figure 5a shows the bracket of figure 1 on an enlarged scale; and Figure 5b shows a perspective veiw of the bracket of Figure 5a.

Referring now to the drawings, it will be seen that the roof spar arrangement 11 comprises a pair of opposed roof spars 12a, 12b. Each spar is comprised by an inner tubular member of steel 13 and an outer sheath of extruded plastics section 14, for example, UPVC. The section 14 is profiled to permit glazing between adjacent spars, as is generally known in the art.

The inner members 13 are joined together at their upper ends in a suitable manner so as to form a stable, rigid joint. Examples of such a rigid joint are shown in Figures 2 to 4. In Figure 2 the two inner members 13 are integral with one another. Preferably, however, they are welded together at their upper ends 15, as shown in Figure 3. Alternatively a metal plate 16 is bolted across the members 13 as shown in Figure 4.

The rigid roof spar as described herein has advantages over conventional non-rigia roof spar arrangements as the weak spot created by a non-rigid joint at the upper ends of two opposing roof spars has been eliminated.

As described above, when a conventional roof spar arrangement is connected to the wall frame of a building, for example a conservatory or greenhouse, the non-rigid joint allows movement in the roof spars, which in turn creates forces which tend to push the wall frames outwards. The rigid roof spar arrangement of the present invention overcomes this problem, but the weight of the rigid roof itself may tend to create inwardly directed forces on the wall frame.

A simple bracket arrangement 18 as shown in Figure 1, and in more detail in Figures 5a and 5b, connecting the rigid roof spar arrangemnt 11 to the wall frame 17 overcomes this problem. The bracket 18 is made of a rigid material and is connectable to the members 13 by screwing thereto the upper face 19 of the bracket 18. The lower face 20 of the bracket 18 is likewise secured to the wall frame 17 by screws 21. The lower face 20 of the bracket 18 extends downwardly forming a flap 22 which abuts the inner edge 23 of the wall frame 17.

The brackets 18 act to transform any inwardly directed forces which may be exerted onto the wall frame by the weight of the rigid roof spar arrangement, into downwardly directed forces thus preventing any lateral movement of the wall frame.

It will be appreciated that it is not intended to limit the invention to the above examples only, many variations, such as might readily occur to one skilled in the art, being possible, without departing from the scope thereof.

Claims (10)

1. A glazed roofing system comprising spars profiled for glazing and fabricated from steel or other material of like rigidity and rigidly connected together at the or an apex of the roofing system whereby substantially to avoid any sagging or spreading of the lower edges of the system without the need to introduce tie bars or other additional internal support.

2. A system according to claim 1, comprising inverted V-members of rigid spars ridgedly joined together.

3. A system according to claim 2, in which the spars are welded together.

4. A system according to claim 2, in which the spars are bolted together.

5. A system according to any one of claims 1 to 4, in which the spars are profiled for glazing by having an outer sheath of extruded material affording the requisite profiles.

6. A system according to claim 5, in which the extruded material is plastics material.

7. A system according to claim 5 or claim 6, in which the extruded material hides welds or bolts joining spars.

8. A system according to any one of claims 1 to 7, in which a small gusset plate or bracket is used to reinforce the rigid connection of the spars.

9. A system according to any one of claims 1 to 8, in which the spars are prefabricated into roof frame members.

10. A system according to any one of claims 1 to 9, in which roof spars are connected to the wall of a building by rigid brackets.