GB2228024A

GB2228024A - Roofing construction

Info

Publication number: GB2228024A
Application number: GB9002341A
Authority: GB
Inventors: Ronald Hutton Gilmour
Original assignee: AVEN BUILDING MAINTENANCE SERV
Current assignee: AVEN BUILDING MAINTENANCE SERV
Priority date: 1989-02-02
Filing date: 1990-02-02
Publication date: 1990-08-15
Also published as: GB8902279D0; GB9002341D0

Abstract

A roofing construction for a building incorporates weather sheeting (10) forming the outer roof supported on purling bars (8) which are connected to the upper ends of rows of spaced height-adjustable columnar support members (6) each presenting at its lower end a pedestal (2) formed for ready attachment to an existing joist (15) of the building. The roofing construction is particularly applicable to the conversion of a flat roof to a pitched roof although it is also suitable for providing the main roof of a new building. Adjustable diagonal braces may be connected between purling 8 and the pedestal 2 of adjacent columns 6. <IMAGE>

Description

ROOFING CONSTRUCTION The subject of this invention is a roof construction which is particularly applicable to the conversion of a flat roof to a pitched roof although it is to be understood that the construction is also suitable for providing the main roof of a new building.

Because of the difficulty of making a flat roof weathertight or maintaining a flat roof weathertight it has often been decided to convert a building having a flat roof to one having a pitched roof and the present invention provides a simple inexpensive construction for doing this although as is stated above the construction can equally well be used to provide the roof of a new building with all the advantages the invention provides of simplicity and cheapness.

According to the invention a roofing construction for a building incorporates weather sheeting forming the outer roof supported on purlin bars and is characterized in that the purlin bars are connected to the upper ends of rows of spaced height-adjustable columnar support members each presenting at its lower end a pedestal formed for ready attachment to an existing joist of the building.

Each columnar support member may comprise a pedestal of inverted channel section having the tips of the channels outwardly turned and formed with holes for reception of means for fixing the pedestal to a joist and a screw-threaded normally vertical rod the lower end portion of which penetrates the pedestal between the flanges thereof and is fixed to the pedestal by nuts on the screw-threaded rod and the upper end of which is arranged to penetrate a purlin bar and to be fixed to the purlin bar by nuts on the screw-threaded rod.

Each columnar support member of selected columnar support members of one row may carry at its lower end a bracket to which one end of a diagonal bracing bar (for example for wind bracing) is attached and each corresponding columnar support member of a preferably adjacent row of columnar support members may carry at its upper end a bracket to which the other end of the diagonal bracing bar is attached.

Where the joists of the building are of timber the pedestals may be attached to the joists by spikes or screws. Where the joists are metal bars the pedestals may be clamped to the joists by U-bolts or other clamping means or they may be screwed directly to the joists.

Sheeting forming the surface of the roof may be attachable to the purlin bars by self-tapping, preferably also self-drilling screws.

A practical embodiment of the invention is illustrated in the accompanying drawings in which Fig. 1 is a detail showing two typical columnar support members attached to a joist and also to purlin bars carrying a roof sheet, Fig. 2 is a perspective view of a columnar support member in position and Fig.

3 is a section through a portion of a roof built according to the invention, the section being the portion of the building at the ridge of the building.

In the drawings 1 denotes a columnar support member comprising a pedestal 2 formed as an inverted channel with the tips of the flanges 3 outwardly turned and formed with holes 4 for passage of fixing spikes 5. 6 denotes a screw-threaded rod fixed to the pedestal 2 by nuts 7 at the lower end and attached to a purlin bar 8 at its upper end by the nuts 9.

10 denotes roof sheeting attached by self-tapping screws 11 to the purlin bars 8. In Fig. 3, 12 denotes a bracket gripped between one of the nuts of the lower end of the rod 6 of a columnar support member and the pedestal 2 of said member and 13 denotes a bracket gripped between the nuts on the screw-threaded rod 6 at the upper end of a corresponding columnar support member and the purlin bar 8 attached to that member. 14 denotes a bracing bar connected between the brackets 12 and 13 to provide wind bracing and 15 denotes a joist of a building to which the roofing construction is fitted. 16 denotes a ridge cap to close the gap at the ridge.

In practice where the joist 15 is a joist of an existing flat roof, to provide a pitched roof over the flat roof the pedestals 2 of columnar support members are fitted to the roof in rows and attached by the spikes 5 driven through the flat roof into the joists supporting the flat roof. Purlin bars 8 are then attached to theupper ends of the vertical rod 6 and the nuts on the screw-threaded rods 6 are so positioned that the operative height of the columns of each successive row from the ridge to the eaves of the building is progressively reduced.

The vertical columns may be cut where necessary.

Roof sheets 10 are then attached to the purlin bars 8 by self-drilling and tapping screws 11 and the ridge cap 16 is put in place. The usual steps are taken, of course, to ensure that the sheeting is itself watertight.

It will be appreciated that whether or not there is an existing flat roof on the building a roof constructed as described can be fitted directly to the joists normally functioning as roof beams in a building.

It will be obvious that the construction provides a simple and extremely cheap and quickly erected method of providing a roof either on an existing flat roof building or the only roof on a new building.

Claims

1. A roofing construction for a building incorporating weather sheeting forming the outer roof supported on purlin bars characterized in that the purlin bars are connected to the upper ends of rows of spaced height-adjustable columnar support members each presenting at its lower end a pedestal formed for ready attachment to an existing joist of the building.

2. A roofing construction according to claim 1, characterized in that each columnar support member comprises a pedestal of inverted channel section having the tips of the channels outwardly turned and formed with holes for reception of means for fixing the pedestal to a joist and a screw-threaded normally vertical rod the lower end portion of which penetrates the pedestal between the flanges thereof and is fixed to the pedestal by nuts on the screwthreaded rod and the upper end of which is arranged to penetrate a purlin bar and to be fixed to the purlin bar by nuts on the screw-threaded rod.

3. A roofing construction according to claim 1, characterized in -that each columnar support member of selected columnar support members of one row carries at its lower end a bracket to which one end of a diagonal bracing bar (for example for wind bracing) is attached and a columnar support member of another row of columnar support members carries at its upper end a bracket to which the other end of the diagonal bracing bar is attached.

4. A roofing construction according to claim 1, in which the joists of the building are of timber, characterized in that the pedestals are attached to the joists by spikes or screws.

5. A roofing construction according to claim 1, in which the joists of the building are metal bars characterized in that the pedestals are clamped to the joists by clamping means.