[0001] The present invention relates to an improved roofing arrangement and in particular
to an improved roofing arrangement for increasing habitable space in attics.
[0002] Traditionally, roofs are provided by using trussed rafters which significantly reduce
the amount of habitable space in the attic, see Figures D, F, G and H. In order to
increase the space in the attic, systems using purlins, see Figures C, E and H and
rafter framing or alternatively modified plate trusses known as attic trusses are
used. The use of purlins and framed rafters mean that skilled roofers have to carefully
and accurately place the purlins before the overlying rafters are built into position.
The purlins are heavy and awkward to work with which increases the health and safety
risk on site. Even with the use of attic trusses, there is a requirement to provide
a horizontal tying member see Figure F at the base of the rafters being a bottom chord
or ceiling tie to restrain the horizontal thrust on the walls which would otherwise
be imposed.
[0003] The load acting on the structural members of the roof is provided by wind load which
gusts against the roof covering elements and is transferred into the roof rafters
and onto the load bearing structures supporting the roof rafters. These load bearing
structures are traditionally provided by load bearing masonry or timber framed walls.
Another direct load occurs as a result of the weight of the roof covering elements
bearing down on the rafters.
[0004] The result of these loads can be roof failure as a result of rafter bending B perpendicular
to the rafter span, see Figures A, E and F and/or roof failure as a result of rafter
thrust T along the line of the rafter span, see Figures A, B, C and D. The standard
roof structures attempt to resolve these problems with increased rafter depth IRD
as shown in Figure B although rafter thrust T is still a problem. The use of purlins
P between the ends of the two inclined framed rafters are shown in Figure C which
reduces the effective span of each rafter and this reduces the bending. However, rafter
thrust T is still a problem. The use of web members W are shown in Figure D which
reduces the effective span of the rafter and this reduces the bending. However, rafter
thrust T is still a problem.
[0005] The use of an apex purlin AP along the apex of the two inclined framed rafters is
shown in Figure E which resists the thrust of each rafter. However, bending B is still
a problem. In Figure F, a chord or ceiling tie C is provided along the ceiling to
resist the thrust of the rafter although bending B is still a problem. Figure G shows
a W truss which resists both bending and thrust however there is no habitable space
in the attic. The use of purlins P between the ends of the two inclined framed rafters
as well as the use of apex purlin AP at the apex is shown in Figure H. This reduces
the bending and thrust of each rafter although retains the problems with purlins already
mentioned above.
[0006] It is an object of the present invention to obviate or mitigate the problems of the
existing systems for increasing habitable space in attics.
[0007] Accordingly, the present invention provides an improved roofing arrangement for a
ridged roof comprising a roof apex reinforcing means, the roof apex reinforcing means
comprising sloping planar reinforcing means tapering to or proximal to the apex of
the ridged roof, the sloping planar reinforcing means being substantially parallel
to a main plane of a sloping portion of the ridged roof, the planar reinforcing means
extending along all or a substantial part of the length of the apex of the roof and
extending along an upper region of at least one sloping portion of the ridged roof.
[0008] Advantageously, the roof apex reinforcing means is provided for resisting thrust
of the rafters or roof members such as roof panels spanning between the eaves and
a location at or about the apex or roof apex reinforcing means.
[0009] Ideally, the roof apex reinforcing means is extendable between and couplable to at
least two end supports for supporting the roof apex reinforcing means down through
a load bearing construction.
[0010] In one embodiment, the roof apex reinforcing means is provided by sheets fixed to
the timber roof rafters on one or both sloping surfaces of the ridged roof proximal
to the apex.
[0011] In this embodiment, the end sheets are mechanically couplable to the end supports.
[0012] In another preferred embodiment, the roof apex reinforcing means is provided by a
reinforced apex beam having two sloping planar reinforcing members tapering to the
apex of the reinforced apex beam, each sloping planar reinforcing member being substantially
parallel to the main plane of the respective sloping portion of the ridged roof, the
planar reinforcing members extending along all or a substantial part of the length
of the reinforced apex beam.
[0013] In this preferred embodiment, the reinforced apex beam has web means extending between
locations at or about the two spaced apart ends of the tapering planar reinforcing
members. Advantageously, the web means reduces the effective length of the span of
the roof rafters or roof members such as roof panels spanning between the eaves and
a location at or about the lower ends of the reinforced apex beam. This reduces the
effect of bending on the span of the roof rafters or the roof members such as roof
panels.
[0014] Ideally, the end supports comprising two gable wall spandrel means.
[0015] Preferably, the improved roofing arrangement comprising a reinforced apex beam extendable
between at least two end supports, the end supports comprising two gable wall spandrel
means for supporting the entire weight of the reinforced apex beam down through a
load bearing construction on which the spandrel means is mountable.
[0016] Ideally, the reinforced apex beam having spaced apart web means extending between
locations at or about the two spaced apart ends of the tapering planar reinforcing
means.
[0017] Preferably, the planar reinforcing means form an outer part of an upper portion of
a ridged roof and extend along all or a substantial part of the length of the reinforced
apex beam.
[0018] Preferably, the web means extends between locations at or about the two lower ends
of the planar reinforcing means.
[0019] Ideally, the end supports comprise two spandrel means for supporting and transferring
the weight of the reinforced apex beam and the load carried thereon down through a
load bearing construction on which the spandrel means is mountable.
[0020] Ideally, the spandrel means has insulation.
[0021] Preferably, the load bearing construction comprises at least two walls, most preferably
gable walls.
[0022] Ideally, the web means comprising spaced apart strut/truss members spaced longitudinally
along the length of the apex beam or between rafters.
[0023] Ideally, the planar reinforcing means extend down along and parallel to both sloping
sides of the ridged roof in use.
[0024] Ideally, the cross-sectional shape of the reinforced apex beam is triangular or truncated
triangular. Advantageously, this shape lends itself to the reinforced apex beam being
placed atop the roofing arrangement so as to complete the generally ridged roof shape.
Further advantageously, the generally triangular shape of the reinforced apex beam
is equally strong in both vertical and horizontal directions and acts as a structurally
efficient triangular prism. All internal supporting webs and/or purlin beams can be
removed leaving clear habitable space.
[0025] Preferably, the ends of the reinforced apex beam are open. Advantageously, this allows
the beam to fold and/or allows the support means to extend into the apex of the reinforced
apex beam.
[0026] Ideally, the reinforced apex beam is torsional rigid.
[0027] Preferably, the reinforced apex beam forms the service void/storage within the roofing
arrangement.
[0028] Preferably, the roofing arrangement further comprising a plurality of bridging components
extending between the base of the reinforced apex beam and a support structure on
which the bridging components are mountable.
[0029] Ideally, the roofing arrangement further comprising a plurality of bridging components
extending between the base of each planar reinforcing means of the reinforced apex
beam and a support structure on which the bridging components are mountable.
[0030] Preferably, support members extend from the lower ends of the planar reinforcing
means of the reinforced apex beam for receiving the bridging members. The support
members are provided by plate members extending downwards from the bottom of the reinforced
apex beam for supporting bridging members.
[0031] Advantageously, the reinforced apex beam having planar reinforcing means extending
down both sloping surfaces of the ridged roof provides a number of structural advantages
for the new roofing arrangement. First of all, the length of the planar reinforcing
means reduces the length of the span of the bridging roof component which extends
between the reinforced apex beam and the eaves wall plate or similar support structure.
This has the benefit of reducing the amount of the bend that the bridging roof component
can encounter because of the shorter distance between the mounting points. This results
in a reduced moment about the central point of the bridging component due to the shorter
span. As a result the normal spreading effect encountered by normal full span rafters
at the wall plate is significantly reduced. Furthermore, because the reinforced apex
beam has both planar reinforcing members and reinforcing strut members acting between
the spaced apart ends of the planar reinforcing members, the rigidity of the overall
apex of the roof structure is significantly improved. There is a reduction in central
downward bending of the reinforced apex beam especially towards the centre of the
reinforced apex beam because of the planar and cross sectional reinforcing means.
[0032] Preferably, coupling means are provided between the lower ends of the planar reinforcing
means and the upper ends of bridging members for mechanically coupling the reinforced
apex beam to the bridging members.
[0033] Ideally, the outside main planar surface of the planar reinforcing means is in alignment
with the outside main planar surface of the bridging components.
[0034] Preferably, the bridging components are provided by building panels.
[0035] Ideally, the bridging components comprise composite building panels.
[0036] Preferably, the composite building panels are structural insulated panels. These
panels comprise a foam member sandwiched by two outer rigid planar board members.
The board can be sheet metal, plywood, cement or oriented strand board (OSB) and the
foam can be either expanded polystyrene foam (EPS), extruded polystyrene foam (XPS),
polyisocyanurate foam, or polyurethane foam.
[0037] In an alternative arrangement, the bridging components can be roof rafters, most
preferably timber roof rafters covered in the traditional way using battens, tiles
or slates.
[0038] Preferably, at least one bridging component has one or more apertures. Advantageously,
the one or more apertures are formed in the roof for receiving roof windows to allow
natural lighting into the living space in the attic.
[0039] Ideally, the bridging components have insulation means.
[0040] Ideally, the structural panels have insulation means.
[0041] Preferably, the reinforced apex beam has insulation means.
[0042] Ideally, the reinforced apex beam has insulation means housed therein.
[0043] Preferably, the reinforced apex beam has insulation means housed therein at ceiling
level.
[0044] Advantageously, the reinforced apex beam and the bridging components having insulation
means allows the insulation to be installed in the factory to surpass strict building
control regulations which can be monitored and supervised so that the products are
sent out to site thermally efficient. This ensures that the thermal values of the
assembled roofing arrangement can be accurately predetermined in the factory reducing
the risk of human error or cost cutting by builders on site.
[0045] Preferably, the reinforced apex beam comprises a framework of longitudinally spaced
apart rafters carrying planar reinforcing means along the outer surface of the rafters.
[0046] Alternatively, the reinforced apex beam comprises a means for coupling the planar
reinforcing means together along the longitudinal length of the beam at or about the
apex and strut/truss means extending between the lower spaced apart ends of the planar
reinforcing means, preferably spaced apart along the longitudinal length of the reinforced
apex beam.
[0047] Ideally, the means for coupling the planar reinforcing means together is a pivotal
coupling arrangement. Advantageously, the pivotal coupling arrangement allows the
apex beam to fold about the pivotal coupling arrangement for more compact storage
and transport.
[0048] Preferably, the strut/truss means is detachably couplable between the lower spaced
apart ends of the planar reinforcing means. Advantageously, the strut/truss means
can be detached to allow the reinforced apex beam to fold for storage and transport.
[0049] Ideally, the planar reinforcing means comprises panel member.
[0050] Preferably, the panel members comprise rigid planar board members.
[0051] Ideally, the board members are sheet metal, plywood, cement or oriented strand board
(OSB) or any combination of these board members.
[0052] Alternatively, the panel members are structural insulated panels. These boards comprise
a foam member sandwiched by two outer rigid planar boards members. The board can be
sheet metal, plywood, cement or oriented strand board (OSB) and the foam can be either
expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), polyisocyanurate
foam, or polyurethane foam.
[0053] Ideally, the planar reinforcing means extend a distance greater than 1/4 m from the
apex of the ridged roof.
[0054] Preferably, the planar reinforcing means extend a distance greater than ½ m from
the apex of the ridged roof.
[0055] Preferably, the planar reinforcing means extend a distance greater than ¾ m from
the apex of the ridged roof.
[0056] Ideally, the planar reinforcing means extend a distance approximately equal to 1
m from the apex of the ridged roof.
[0057] Ideally, the planar reinforcing means extend a distance less than 1½ m from the apex
of the ridged roof.
[0058] Preferably, the planar reinforcing means extend a distance less than 1 ¼ m from the
apex of the ridged roof.
[0059] The invention will now be described with reference to the accompanying drawings which
show by way of example only one embodiment of a roofing arrangement in accordance
with the invention. In the drawings:-
Figure A is a schematic drawing of a simple two beam roof rafter;
Figure B is a schematic drawing of a simple increased rafter depth two beam roof rafter;
Figure C is a schematic drawing of a simple two beam roof rafter with purlins;
Figure D is a schematic drawing of a trussed roof rafter;
Figure E is a schematic drawing of a simple two beam roof rafter with an apex purlin;
Figure F is a schematic drawing of a simple two beam roof rafter with a ceiling tie;
Figure G is a schematic drawing of a W truss roof rafter;
Figure H is a schematic drawing of a simple two beam roof rafter with an apex purlin
and two mid span purlins;
Figure 1 is an exploded perspective view of a first embodiment of roofing arrangement
in accordance with the invention;
Figure 2 is a perspective view of an assembled roofing arrangement as shown in Figure
1;
Figure 3 is a detail schematic view of a first embodiment of reinforced apex beam;
Figure 4 is a detail schematic view of a second embodiment of reinforced apex beam;
Figure 5 is a schematic view of forces acting on the reinforced apex beam;
Figure 6 is a schematic view of the structural elements making up the roofing arrangement;
Figure 7 is a perspective view of a second embodiment of roofing arrangement in accordance
with the invention;
Figure 8 is an end view of the second embodiment of roofing arrangement; and
Figure 9 is a schematic drawing showing the concept of the reinforced triangular prism
created by the first or second embodiment of roofing arrangement.
[0060] In Figures 1 to 6 of the drawings, there is shown a first embodiment of roofing arrangement
indicated generally by the reference numeral 1 having a reinforced apex beam 2 extendable
between two end supports 3. The reinforced apex beam 2 having planar reinforcing members
4 tapering towards the apex 13 of the reinforced apex beam 2. The planar reinforcing
members 4 form an integral upper part of a ridged roof and extend along all of the
length of the reinforced apex beam 2. The reinforced apex beam 2 has web members 5
acting as a strut/tie and extending between the planar reinforcing members 4. The
web members 5 extends between locations at or about the two lower ends of the planar
reinforcing members 4. The end supports 3 are two spandrel truncated triangular panels
3 for supporting and transferring the weight of the reinforced apex beam 2 and the
load carried thereon down through a load bearing construction 6 on which the spandrel
truncated triangular panels 3 are mounted. The spandrel truncated triangular panels
3 are insulated. The load bearing construction 6 is provided by two gable walls 6.
[0061] The web members 5 are provided by spaced apart truss members 7 spaced longitudinally
along the length of the apex beam 2 as shown in Figures 3 and 4. The planar reinforcing
members 4 extend partly down along and parallel to both sloping sides of the ridged
roof in use. The cross-sectional shape of the reinforced apex beam 2 is generally
triangular. Advantageously, this shape lends itself to the reinforced apex beam 2
being placed atop the roofing arrangement 1 so as to complete the generally ridged
roof shape. Further advantageously, the generally triangular shape of the reinforced
apex beam 2 is equally strong in both vertical and horizontal directions as illustrated
in Figure 5. The reinforced apex beam 2 is torsional rigid. The reinforced apex beam
2 forms the service void/storage area 8 within the roofing arrangement 1.
[0062] The roofing arrangement 1 has five bridging components 11 extending between the base
of the reinforced apex beam 2 and each load bearing wall 12 on which the roofing arrangement
1 is mounted, see especially Figure 2. The five bridging components 11 extend between
the base of the planar reinforcing members 4 and the load bearing walls 12 on which
the bridging components 11 are mounted. Support members, not shown, extend or protrude
from the lower ends of the planar reinforcing members 4 of the reinforced apex beam
2 for receiving the bridging members 11. The support members are provided by plate
members extending downwards from the bottom of the reinforced apex beam 2 for supporting
bridging members 11. Advantageously, the reinforced apex beam 2 having planar reinforcing
members 4 extending down both sloping surfaces of the ridged roof provides a number
of structural advantages for the new roofing arrangement 1. First of all, the length
of the planar reinforcing members 4 reduces the length of the span of the bridging
roof components 11 which extends between the reinforced apex beam 2 and the eaves
wall plate or similar support structure. This has the benefit of reducing the amount
of bend that the bridging roof components 11 can encounter because of the shorter
distance between the mounting points. This results in a reduced moment about the central
point of the bridging component 11 due to the shorter span. As a result the normal
spreading effect encountered by normal full span rafters of traditional roof trusses
at the wall plate is significantly reduced. Furthermore, because the reinforced apex
beam 2 has both planar reinforcing members 4 and reinforcing strut/tie members 5 acting
between the spaced apart ends of the planar reinforcing members 4, the rigidity of
the overall apex of the roof arrangement 1 is significantly improved. There is a reduction
in central downward bending of the reinforced apex beam 2 especially towards the centre
of the reinforced apex beam 2 because of the planar and cross sectional reinforcing
members 4, 5.
[0063] Coupling members, not shown, are provided between the lower ends of the planar reinforcing
members 4 and the upper ends of bridging members 11 for mechanically coupling the
reinforced apex beam 2 to the bridging members 11.
[0064] The outside main planar surface of the planar reinforcing member 4 is in alignment
with the outside main planar surface of the bridging components 11. The bridging components
11 are provided by building panels, composite building panels being structural insulated
panels. These panels comprise a foam member sandwiched by two outer rigid planar board
members. The board can be sheet metal, plywood, cement or oriented strand board (OSB)
and the foam can be either expanded polystyrene foam (EPS), extruded polystyrene foam
(XPS), polyisocyanurate foam, or polyurethane foam.
[0065] One bridging component 11 has one aperture 21. Advantageously, the aperture 21 is
formed in the roof arrangement 1 for receiving a roof window for example to allow
natural lighting into the living space in the attic. The bridging components 11 have
integrally formed insulation. The reinforced apex beam 2 has insulation housed therein
at ceiling level. This avoids the requirement for insulation above this level. Advantageously,
the reinforced apex beam 2 and the bridging components 11 having insulation allows
the insulation to be installed in the factory to surpass strict building control regulations
which can be monitored and supervised so that the components of the roofing arrangement
1 are sent out to site thermally efficient. This ensures that the thermal values of
the assembled roofing arrangement 1 can be accurately predetermined in the factory
reducing the risk of human error or cost cutting by builders on site.
[0066] Referring more particularly to Figure 4, the reinforced apex beam 2 has a framework
of longitudinally spaced apart rafters 31 carrying planar reinforcing members 4 along
the outer surface of the rafters 31. Alternatively, as shown in figure 3, the reinforced
apex beam 2 has an elongate beam 33 for coupling the planar reinforcing members 4
together along the longitudinal length of the apex beam 2 at or about the apex and
strut/tie members 34 extending between the lower spaced apart ends of the planar reinforcing
members 4 spaced apart along the longitudinal length of the reinforced apex beam 2.
The elongate beam 33 for coupling the planar reinforcing members 4 together is a pivotal
coupling arrangement. Advantageously, the pivotal coupling arrangement allows the
apex beam 2 to fold about the pivotal coupling arrangement for more compact storage
and transport. In this particular embodiment, the strut/tie members 5 are detachably
couplable between the lower spaced apart ends of the planar reinforcing members 4.
Advantageously, the strut/tie members 5 can be detached to allow the reinforced apex
beam 2 to fold for storage and transport. The planar reinforcing members 4 are panel
member having rigid planar board members. The board members are sheet metal, plywood,
cement or oriented strand board (OSB) or any combination of these board members.
[0067] Alternatively, the panel members are structural insulated panels. These boards comprise
a foam member sandwiched by two outer rigid planar boards members. The board can be
sheet metal, plywood, cement or oriented strand board (OSB) and the foam can be either
expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), polyisocyanurate
foam, or polyurethane foam.
[0068] All or a part of the outside surface of the apex beam and the bridging elements have
a roof covering material formed thereon in the factory such as a preformed cladding
or panels. Alternatively, all or a part of the outside surface of the apex beam and
the bridging elements have a traditional roof covering material applied. The planar
reinforcing means extend a distance in a range from ¼ m from the apex of the ridge
to a distance less than 1 ¾ m from the apex of the ridge. Although it will of course
be appreciated that the reinforced apex beam can be designed to have any desired depth
to accommodate the specific load bearing requirements for any dimension of roof configuration.
[0069] In a second embodiment of roofing arrangement, shown in Figures 7 and 8 of the drawings,
the bridging components can be roof rafters 41 with the roof apex reinforcing arrangement
provided by sheets 42 fixed to the timber roof rafters 41 on one or both sloping surfaces
43 of the ridged roof proximal to the apex 44. In this embodiment, the ends of the
sheets 42 are mechanically coupled to the end supports. As shown in Figure 8, struts/ties
45 are provided between the rafters 41 to reduce bending B by reducing the effective
length of the span of the rafters 41.
[0070] Referring to Figure 9, the cross-sectional shape of the reinforced apex beam 2 of
the first roofing arrangement or the planar reinforcing members 41 and strut/tie members
45 of the second embodiment of roofing arrangement is triangular. Advantageously,
the generally triangular shape of the reinforced apex beam 2 or the planar reinforcing
members 41 and strut/tie members 45 are equally strong in both vertical and horizontal
directions and acts as a structurally efficient triangular prism. All internal supporting
webs and/or purlin beams can be removed leaving clear habitable space. The remainder
of the roof space is infilled with rafters 41 or prefabricated panels 11.
[0071] In relation to the detailed description of the different embodiments of the invention,
it will be understood that one or more technical features of one embodiment can be
used in combination with one or more technical features of any other embodiment where
the transferred use of the one or more technical features would be immediately apparent
to a person of ordinary skill in the art to carry out a similar function in a similar
way on the other embodiment.
[0072] In the preceding discussion of the invention, unless stated to the contrary, the
disclosure of alternative values for the upper or lower limit of the permitted range
of a parameter, coupled with an indication that one of the said values is more highly
preferred than the other, is to be construed as an implied statement that each intermediate
value of said parameter, lying between the more preferred and the less preferred of
said alternatives, is itself preferred to said less preferred value and also to each
value lying between said less preferred value and said intermediate value.
[0073] The features disclosed in the foregoing description or the following drawings, expressed
in their specific forms or in terms of a means for performing a disclosed function,
or a method or a process of attaining the disclosed result, as appropriate, may separately,
or in any combination of such features be utilised for realising the invention in
diverse forms thereof as defined in the appended claims.
1. An improved roofing arrangement for a ridged roof comprising a roof apex reinforcing
means, the roof apex reinforcing means comprising sloping planar reinforcing means
tapering to or proximal to the apex of the ridged roof, the sloping planar reinforcing
means being substantially parallel to a main plane of a sloping portion of the ridged
roof, the planar reinforcing means extending along all or a substantial part of the
length of the apex of the roof and extending along an upper region of at least one
sloping portion of the ridged roof.
2. An improved roofing arrangement as claimed in claim 1, wherein the roof apex reinforcing
means is extendable between and couplable to at least two end supports for supporting
the roof apex reinforcing means down through a load bearing construction.
3. An improved roofing arrangement as claimed in claim 1 or claim 2, wherein the roof
apex reinforcing means is provided by a reinforced apex beam having two sloping planar
reinforcing members tapering to the apex of the reinforced apex beam, each sloping
planar reinforcing member being substantially parallel to the main plane of the respective
sloping portion of the ridged roof, the planar reinforcing members extending along
all or a substantial part of the length of the reinforced apex beam.
4. An improved roofing arrangement as claimed in claim 3, wherein the reinforced apex
beam has spaced apart web means extending between locations at or about the two spaced
apart ends of the tapering planar reinforcing members.
5. An improved roofing arrangement as claimed in any one of claims 2 to 4, wherein the
end supports comprising two gable wall spandrel means.
6. An improved roofing arrangement as claimed in claim 5, wherein the spandrel means
has insulation.
7. An improved roofing arrangement as claimed in any one of claims 3 to 6, wherein the
planar reinforcing means form an outer part of an upper portion of a ridged roof and
extend along all or a substantial part of the length of the reinforced apex beam.
8. An improved roofing arrangement as claimed in any one of claims 4 to 7, wherein the
web means comprising spaced apart strut/truss members spaced longitudinally along
the length of the apex beam.
9. An improved roofing arrangement as claimed in any one of claims 3 to 8, wherein the
cross-sectional shape of the reinforced apex beam is triangular or truncated triangular.
10. An improved roofing arrangement as claimed in any one of claims 3 to 9, wherein the
ends of the reinforced apex beam are open.
11. An improved roofing arrangement as claimed in any one of claims 3 to 10, wherein the
reinforced apex beam is torsional rigid.
12. An improved roofing arrangement as claimed in any one of claims 3 to 11, wherein the
reinforced apex beam forms the service void/storage within the roofing arrangement.
13. An improved roofing arrangement as claimed in any one of claims 3 to 12, wherein the
roofing arrangement further comprising a plurality of bridging components extending
between the base of the reinforced apex beam and a support structure on which the
bridging components are mountable.
14. An improved roofing arrangement as claimed in any one of claims 3 to 13, wherein support
members extend from the lower ends of the planar reinforcing means of the reinforced
apex beam for receiving the bridging members.
15. An improved roofing arrangement as claimed in any one of claims 13 or 14, wherein
the bridging components and/or the reinforced apex beam have insulation means.