ROOFING STRIP

Abstract: A strip of roofing material, the strip being formed from sheet metal and having a web and C-shaped channel portions (8, 6, 9 and 11, 10, 12) extending along opposed edges of the web. When the strip is used in a roof, the C-shaped channels interlock with one another so as to form box beams which provide considerable support for the strips in a roof.

Description: ROOFING STRIP This invention relates to roofing material, particularly roofing material made from sheet metal. The object of the present invention is to provide a novel configuration of roofing material of sheet material which is provided in strip form, the strips being arranged, in use, so as to run generally in horizontal directions with the upper strips overlapping the successively lower strips so as to provide a weatherproof roof structure- According to the present invention there is provided roofing material comprising a web having a first flange which extends from one edge thereof in a first direction and a second flange which extends from the other edge thereof in the opposite direction to the first flange, the arrangement being such that in use a roof is formed from the roofing material with strips of said material extending generally horizontally with the first flange of a relatively low strip underlying and extending towards the web of the next successively uppermost strip, and wherein the second flange of the next uppermost strip has its second flange extending towards the web of the lower strip whereby said first flange of the lower strip and the second flange of the upper strip and adjacent portions of the webs of said strips together define a hollow beam of polygonal cross-section. The invention also provides a roofing strip having an elongate web portion with upturned and downturned side flanges at the longitudinal edges of the web, the arrangement being such that the strips can be overlapped to form a roof and the flanges and adjacent portions of the web form hollow beam members for strengthening the strips on the roof. The invention also includes a roof made from a plurality of the strips defined above. The invention will now be further described with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view of a preferred embodiment of the strip of the invention; FIGURE 2 is a schematic side view of a roof structure incorporating the strip of the invention; FIGURE 3 is a cross-sectional view taken along the line 3-3; and FIGURE 4 is a cross-sectional view taken along the line 4-4. The roofing strip 2 of the invention is made from sheet metal such as aluminium, galvanized iron or steel coated with a protective finish. The strip comprises a web portion 4, upturned flange 6 and upper leg 8. The strip further includes a downwardly extending flange 10 with a lower leg 12. At one side of the web 4 of the strip there is formed a first marginal portion 9 which is perpendicular to the adjacent flange 6 and parallel to the upper leg 8. At the other side of the web 4 there is formed a second marginal portion 11 which is perpendicular to the flange 10 and parallel to the lower leg 12. The arrangement is such that the marginal portion 9 and the lower leg 12 lie in the same plane. Similarly, the upper leg 8 and the marginal plane 11 lie in a common plane which is parallel to the plane which includes the portion 9 and leg 12. Figure 2 shows the use of the roofing strips to form a roof. The lower part of the drawing shows the strips used with a roof having a timber truss 13 whereas the upper part of the drawing shows the use of the strips with a steel truss 15. In both arrangements the trusses have top faces indicated at 17 which may extend at an angle to the horizontal depending upon the pitch of the roof, the right hand side (as shown in Figure 2) being higher than the left hand side. The drawing shows a first strip 2a, part of a successively lower strip 2b and part of a successively upper strip 2c. In fabricating a roof, the lowermost strips would be affixed first to the trusses and the successively upper strips added so as to form the surface of the roof. It will be seen that the portion 9b of the strip 2b lies flush against the top surface 17 of the truss 13. The leg 6b extends perpendicularly with respect to the top surface 17. The leg 6b includes holes 19b through which fixing bolts 21 pass. Each fixing bolt 21 is generally U-shaped and its the lower end is threaded. The fixing bolts 21 are connected to the timber truss 13 by means of a bracket 23 which has a U-shaped portion 25 and side flanges 27, as best seen in Figure 4. The threaded portions of the fixing bolts 21 pass through openings in the side flanges and nuts 29 are tightened so that their free ends 31 bear against the undersides of the side flanges and so clamp the portion 9b into firm contact with the top surface 17 of the truss. In fabricating the roof the nuts 29 are initially left somewhat loose so that the lower leg 12a of the next uppermost strip can be inserted between the free end 31 of the fixing bolt 21 and the adjacent marginal portion 9b until the leg 12a overlies substantially the entire portion 9b. Further, the marginal portion 11a overlies and engages the upper leg 8b. Once the two strips 2a and 2b are in this relative position, the nuts 29 can be tightened so that the strips are firmly locked together. The free end 31 of the fixing bolts preferably come into engagement with the leg 12a so as to clamp the position of the strip 2a. All of the strips required in the roof could be clamped together and to the trusses in a similar manner. For ease of fabrication, the brackets 23 can be nailed to the trusses 13 so as to hold them in position until the fixing bolts 21 and nuts 29 have been positioned and tightened. This is most easily accomplished by providing holes 31 in the U-shaped portions 25 through which a nails 33 can be driven. Figure 2 also shows the use of the roofing strips with a steel truss 15. In this arrangement the truss includes a pair of angle irons 35, as best seen in Figure 3. The fixing bolts 21 can pass through holes provided directly in the upper flanges of the angle irons 35 and tightened so as to clamp the strips to the truss 15 in a similar manner described with reference to the timber truss 13. It will be seen from Figure 2 that the interlocking portions of the strips form box beams which possess considerable strength. More particularly, it will be seen that the portions 11a and 9b, flanges 10a, 6b and legs 12a and 8b together form a box beam of rectangular section which strengthens and supports the edges of the webs of the strips. The box beam of course extends between adjacent trusses of the roof and thereby eliminates the need for battens which are required in a normal roofing structure. Figure 2 also shows a modified arrangement in which a downward leg 37b (shown in broken lines) extends downwardly from the leg 8b. The inclusion of downward legs 37 on the strips would increase the strength of the box beams formed at the edges of the webs of the strips. In a preferred arrangement, the distance between the flanges 6 and 10 is 350 mm, the widths of the portions 9 and 11 is 25 mm and the height of the flanges 6 and 10 are 50 m . The legs 8 and 12 are somewhat less than 25 mm in length. In this arrangement the angle between the web 4 and the marginal portions 9 and 11 is about 10°. These dimensions of course can be altered for different applications. It will be appreciated that the strips of the invention can be used to provide an easily assembled and water tight roofing structure. Further the roof is of attractive appearance. Moreover the technique of fixing the strips to the trusses is such that the trusses are not perforated at locations which are exposed to the elements so that the likelihood of water leakage is extremely small. The strips could be supplied from a factory in convenient lengths of say 5 or 10 metres. Alternatively a portable rolling apparatus could be used to form the strips on site in very long lengths if required. Many modifications will be apparent to those skilled in the art without departing from the spirit and scope of the invention.

Claims: CLAIMS : 1. Roofing material comprising a web (4) having a first flange (6) which extends from one edge thereof in a first direction and a second flange (10) which extends from the other edge thereof in the opposite direction to the first flange, the arrangement being such that in use a roof is formed from the roofing material with strips of said material extending generally horizontally with the first flange (6b) of a relatively low strip (2b) underlying and extending towards the web (4a) of the next successively uppermost strip, and wherein the second flange (10a) of the next uppermost strip (2a) has its second flange extending towards the web (4b) of the lower strip whereby said first flange (6b) of the lower strip and the second flange (10a) of the upper strip and adjacent portions (11a, 9b) of the webs of said strips together define a hollow beam of polygonal cross-section. 2. A roofing material as claimed in claim 1 including an upper leg (8) which extends from the first flange (6) transversely thereto and in a direction generally towards the web. 3. Roofing material as claimed in claim 2 including a lower leg (12) which extends from the second flange (10) transversely thereto and in a direction generally towards the web. 4. Roofing material as claimed in claim 2 or 3 wherein the web includes first and second marginal portions (9, 11) adjacent to the first and second flanges respectively said first and second marginal portions being parallel to the upper and lower legs respectively. 5. Roofing material as claimed in claim 4 wherein the upper leg (8) and the second marginal portion (11) lie generally in a first common plane and the lower leg (12) and the first marginal portion (9) lie generally in a second common plane. 6. Roofing material as claimed in claim 5 wherein the widths of said legs and said marginal portions are substantially the same. 7. A roof including truss means (13, 15), a plurality of strips of roofing material as claimed in claim 1 or 5, and fixing means (21) for fixing the strips to the truss means, said strips extending across the truss means whereby the beams of polygonal cross-section provide support for the strips between the truss means. 8. A roof as claimed in claim 7 wherein the fixing means includes bolts (21) which extend from the first flanges (6) to the truss means. 9. A roof as claimed in claim 8 wherein said bolts are generally U-shaped and pass through openings (19) in the first flanges, the openings (19) being spaced from the first marginal portions. 10. A roof as claimed in claim 9 wherein the second flanges are imperforate. 11. A strip of roofing material said strip being integrally formed and comprising a web (4) and a first channel portion (8, 6, 9) and a second channel portion (11, 10, 12) which extend along opposed edges of the web, the channel portions being C-shaped in cross-section and opposed to one another. 12. A strip as claimed in claim 11 wherein the first channel portion includes an upper leg (8) , lower leg (9) and intermediate leg (6) and the second channel portion includes an upper leg (11), lower leg (12) and intermediate leg (10), and wherein the web extends between the free edges of the lower leg (9) of the first channel portion and the upper leg (11) of the second channel portion. 13. A strip as claimed in claim 12 wherein the upper legs (8, 11) lie in a first common plane and the lower legs (9, 12) lie in a second common plane and wherein the intermediate legs (6, 10) lie in planes which are perpendicular to said first and second common planes.

Inventors: BRASSE FREDI WILHELM, BRASSE, FREDI, WILHELM
Applicants: BRASSE FREDI WILHELM, BRASSE, FREDI, WILHELM
Application year: 1985
Main classification: E04D3
IPC codes: E04D3