[0001] The invention relates to a roof element comprising at least substantially channel-section
beams extending in the direction of length of the roof element and being made of sheet
material and plates fastened to said beams.
[0002] In known roof elements of the kind set forth the top ends of the limbs of the channel-section
beams are fastened to wooden beams extending parallel to said limbs, on which wooden
beams wooden boards are secured. The various components of such a roof element are
interconnected by glue joints. This results in a complicated structure of the roof
element whilst the use of glue joints established under pressure and requiring a given
period of time for drying brings about a delay in the manufacturing process.
[0003] The invention has for its object to provide a roof element of the kind set forth
above in which the disadvantages inherent in the conventional constructions can be
avoided.
[0004] According to the invention this can be achieved by providing the channel-section
beams at the free ends of their limbs with bent-over flanges, which are fastened with
the aid of nails or bolts to corrugated plates of sheet material directly bearing
on said flanges.
[0005] By using this construction a roof element of simple and light-weight design can be
obtained, whilst the components can be readily and effectively fastened to one another
by means of nails or bolts without adversely affecting protective layers, which may
have been applied to the parts of sheet material.
[0006] Preferably the corrugations of the plates extend transversely of the direction of
length of the beams so that, when placing the roof elements side by side to form a
roof, the corrugated plates can overlap one another and be fastened-to one another
with the aid of bolts or nails to obtain a solid connection between the adjacent roof
elements.
[0007] The invention will now be described more fully with reference to an embodiment of
the construction in accordance with the invention shown in the accompanying Figures.
Fig. 1 is a plan view of a roof element embodying the invention.
Fig. 2 is a sectional view taken on the line II-II in Fig. 1.
Fig. 3 is an enlarged sectional view taken on the line III-III in Fig. 1 with the
support on a roof joist.
Fig. 4 is a sectional view taken on the line IV-IV in Fig. 3, the longitudinal beams
of the roof element being omitted.
[0008] The roof element shown in the Figures comprises two relatively parallel longitudinal
beams 1 and 2, each having an at least substantially U-shaped cross-section. Each
longitudinal beam is made from thin, folded sheet material having a thickness of 1
to 2 mms in accordance with the length of the longitudinal beam concerned. Fig. 2,
in particular, shows that each longitudinal beam has a lower web 3 interconnecting
the two limbs 4 and 5 of the beam concerned, said limbs being upwardly inclined away
from one another and from the web 3. At their top ends the limbs 4 and 5 terminate
in flanges 6 and 7 lying in the same plane and being outwardly bent over with respect
to the limbs 4 and 5, the outer edges 8 and 9 of said flanges being bent over inwardly.
[0009] On the coplanar flanges 6 and 7 of the two longitudinal beams 1 and 2 are bearing
corrugated plates 10 also of thin sheet material, the cross-section of which comprises
lower, flat parts 11 forming the valleys and flat parts 12 forming the peaks and lying
between the former, viewed on plan, the flat parts 11 and 12 being interconnected
by tie parts 13 upwardly inclined away from the flat parts 11 and away from one another.
From Fig. 3 it will be apparent that the arrangement is such that the corrugations
of the plate 10 are perpendicular to the direction of length of the beams 1 and 2.
[0010] The flat parts 11 of the corrugation plate 10 are directly bearing on the flanges
6 and 7 of the beams 1 and 2 are secured to said flanges with the aid of bolts or
nails 14 shown schematically. This mode of connection between the corrugated plate
10 and the flanges of the beams 1 and 2 prevents the limbs 4 and 5 of the beams 1
and 2 from relatively shifting in place due to loads or the like.
[0011] On the top side of the corrugated plate is arranged a plate 15 of insulating material.
The width of this plate is slightly smaller than that of the corrugated plate 10,
as will be seen from Fig. 2. The insulating material 15 is covered with strips of
roofing material 16, which overlap one another, as is shown in Fig. 2, in order to
obtain water-tight covering.
[0012] In order to obtain an effective support for the roof element described two profiled
beams 17 may be arranged at each end of the roof element as is shown in Figs. 3 and
4. Each beam 17 is located by part of its length between the limbs 4 and 5 of a beam
1 and 2 respectively, whereas the remaining part of the beam 17 concerned protrudes
out of the beam 1 and 2 respectively. This protruding end of the beam 17 may be used
for supporting the roof element on a girder 18 of the steel or concrete structure
of a building to be provided with a roof composed of roof elements of the type described
above.
[0013] It will in particular be apparent from Fig 4 that each beam 17 has a more or less
W-shaped cross-section having a flat central part fastened with the aid of nails or
bolts 19 to the corrugated plate 10. The outer limbs of the beams 17 are secured by
nails or bolts 20 to the limbs 4 and 5 of the beams 1 and 2 respectively (not shown
in Fig. 4).
[0014] Fig. 3 furthermore shows that the ends of the beams 17 extending beyond the beams
1 and 2 may be covered with the aid of a covering plate 21 adjoining the end of the
corrugated plate 10 and supporting, in addition the end of the insulating plate 15.
[0015] If desired, a ceiling board 22 may be fastened to the underside of the parts 3 of
the beams 1 and 2 in the manner shown.
[0016] The roof element described above can be fully prefabricated in a factory or the like.
With regard to transport purposes the width of the roof element is preferably about
240 cms. The length of the roof element depends of the size of the span to be covered
and may vary, for example, between 8 and 17 metres. As stated above, the thickness
of the metal sheet used to form the beams 1 and 2 and the corrugated plate will be
chosen in accordance with the size of the span and it will usually vary between about
0.63 mm and 2.5 mms.
[0017] In assembling a roof a plurality of the roof elements depicted above are arranged
side by side in a manner such that the parts of the corrugated plates protruding beyond
the insulating material at least partly overlap one another. These overlapping parts
of the corrugated plates can be fastened to one another with the aid of bolts or nails
passed through the parts 11 of the corrugated plates. Subsequently the gaps formed
between the covering layers of insulating material can be filled out with insulating
material, after which in the areas of the junctions of the roof elements further roofing
material is arranged in order to complete the roof in a water-tight manner.
[0018] In this way a light-weight, firm roof can be formed, in which the corrugated plates
10 not only ensure that the beams 1 and 2, even when loaded, will not deform, but
also provide sufficient strength of the roof to permit of walking thereon. The roof
elements thus formed are particularly rigid so that in a building provided with a
roof formed by such roof elements wind resisting jointing may usually be fully dispensed
with. Owing to the mode of supporting the roof elements described above and illustrated
in Figs. 3 and 4 the beams 1 and 2 of the roof elements are located between the joists
18 forming part of the skeleton of the building, which contributes to a reduction
of the structural height of the building and hence to a reduction of building costs.
[0019] From the foregoing it will be obvious that by using a roof element embodying the
invention a particularly light-weight and compact structure can be obtained, which
can have a high, cost-saving effect.
[0020] The figures used in the claims are only meant to explain more clearly the intention
of the invention and are not supposed to be any restriction concerning the interpretation
of the invention.
1. A roof element comprising at least substantially channel-section beams extending
in the direction of length of the roof element and being made from sheet material
and plates fastened to said beams characterized in that at the free ends of their
limbs the channel-section beams are provided with bent-over flanges which are fastened
with the aid of nails or bolts to corrugated plates of sheet material directly bearing
on said flanges.
2. A roof element as claimed in Claim 1 characterized in that the corrugations of
the corrugated plate extend transversely of the direction of length of the beams.
3. A roof element as claimed in Claim 1 or 2 characterized in that the limbs of a
channel-section beam are upwardly inclined away from one another and away from a flat
web interconnecting the limbs and lying on the underside of the beam.
4. A roof element as claimed in anyone of the preceding Claims characterized in that
the flanges of the beams have downwardly bent-over outer rims.
5. A roof element as claimed in anyone of the preceding Claims characterized in that
the corrugated plate comprises relatively parallel parts located at different levels
and interconnected with the aid of tie parts upwardly inclined away from the lower
flat parts and away from one another.
6. A roof element as claimed in Claim 5 characterized in that the lower flat parts
of the corrugated plate bear on the flanges of the beams and are secured to said flanges
with the aid of bolts or nails.
7. A roof element as claimed in anyone of the preceding Claims characterized in that
supporting beams protruding beyond the beams and fastened to the corrugated plate
are secured to the ends of the roof element.
8. A roof element as claimed in Claim 7 characterized in that the supporting beams
have a more or less W-shaped cross-section and are fastened by a flat central part
to the corrugated plate.
9. A roof element as claimed in Claim 7 or 8 characterized in that the outermost parts
of a supporting beam are in engagement with the inner side of the limbs of the channel-section
beam and are fastened to said limbs.
10. A roof element as claimed in anyone of Claims 7 to 9 characterized in that the
height of a supporting beam is smaller than one fifth of the height of the channel-section
beam.
11. A roof element as claimed in any preceding Claim characterized in that the height
of the channel beam is greater as its width.
12. A roof element as claimed in any preceding Claim characterized in that the height
of the corrugations is less as 1/4 of the height of the channel beam.