EP2674540A1

EP2674540A1 - Roof panel

Info

Publication number: EP2674540A1
Application number: EP13168543.0A
Authority: EP
Inventors: Tim Harris
Original assignee: My Four Walls (UK) Ltd
Current assignee: My Four Walls (UK) Ltd
Priority date: 2012-05-21
Filing date: 2013-05-21
Publication date: 2013-12-18
Also published as: GB2502286A; GB201208948D0

Abstract

A structural roof panel (10) comprising a single wooden skin (12) together with a rigid foam insulation layer (26), the wooden skin (12) having oppositely disposed flange parts (36, 38) adapted to cooperate in use with rafters (70, 72) a roof structure as part of a modular roofing system. Structural strength is provided by a metal support beam (40) formed integrally with the wooden skin (12). Location of the roof panel (10) with the rafters (70, 72) is provided by a pair of spring loaded sliding pins (57, 58) allowing the panel (10) to simply clip in place.

Description

The present invention relates to a roof structure, and in particular, but without limitation to, a structural panel for use in forming a roof structure made from a number of interconnectable parts, and to a fixing system for a structural panel.
There is a requirement for a roof system that can be fitted to an existing structure, such as a conservatory frame work, to provide a "real" roof, e.g. a tile, slate, or other solid effect roof, as an alternative to or as a replacement for the traditional glazed conservatory roof. A glazed roof has the benefit of making a room light and airy, but is less energy efficient than a solid roof, especially an insulated roof construction.
One known solution is to construct from scratch a boarded roof to fit onto the existing wall structure. This involves constructing a support structure of beams and rafters, to which is attached any required insulation, a breather membrane, battens spanning the rafters and finally the finished roof effect is applied, e.g. tiles. Such a construction is time consuming to erect, taking several days of skilled labour for a typical roof construction.
Another known solution is to use large structural insulated panels or SIPS as they are known. These come in sheets that are typically 2.4m x 1.2m in size and comprise a layer of rigid foam insulation sandwiched between upper and lower skins of wood, usually an oriented strand board. The sandwich construction gives the panels good structural strength allowing the panels to span large distances. However, the need for two skins of wood makes them heavy. Furthermore, their large size makes them awkward to handle and, unless custom made off-site, they need to be modified to fit which slows down their installation. In addition, provision has to be made for fixing them together.
The present invention aims to provide an alternative solution.
Accordingly a first aspect of the invention provides a structural panel comprising a single skin of wood having a foam insulation layer on at least part of one face and further comprising at least one structural beam formed integrally therewith.
The wood of the single skin may be solid wood but more usually it will be oriented strand board or some other type of particle board or wood composite. Any suitable foam insulation material may be used, usually a closed cell foam material, and more particularly a rigid urethane foam insulation material. The thickness of the foam layer is chosen to provide the desired level of thermal insulation.
The integral beam aids structural integrity of the roof panel and is preferably made form a light alloy material such as aluminium to minimise the weight of the panel. In some applications other materials may be appropriate, such as steel. In the case of steel the beam may be fabricated from sheet steel. In the case of aluminium, the beam may be formed as an extrusion. It may be formed from one or more parts. The beam may have a box shaped cross-section or it may be I-shaped in cross-section. A preferred beam construction is formed from two components that are linked together by a connecting element that provides a thermal break between inner and outer elements of the beam. In the case of an I-shaped beam, the central web may be a single web or more preferably a double web. The connecting element preferably comprises an elongate rod, preferably made of plastic or other thermal insulating material, and engages with cupped formations of respective web parts to secure the two parts of the beam together as well as providing the thermal break. The beam caries means for securing the panel to supporting elements of the roof structure and further details are described hereinafter.
An outer flange or surface of the beam is adhered to or otherwise secured to the inner face of the wood skin. The wood skin has length and width defining longitudinal edges and lateral sides. The integral beam may extend across the entire width of the wood skin, but more preferably it terminates short of the lateral sides. Preferably the integral beam is located immediately adjacent one longitudinal edge of the wood skin although this is not necessarily essential. There may be one beam disposed intermediate the longitudinal edges, or more than one beam disposed at spaced longitudinal intervals where structural strength so dictates.
The foam layer may extend contemporaneously with the wood, but more preferably its width-wise extent terminates short of the lateral sides of the wood skin, usually aligned with the ends of the integral beam, and its longitudinal extent is from one longitudinal edge of the wood skin up to the integral beam. Where there is more than one beam the insulation layer extends between the or each of the beams.
By terminating the beam and foam layer short of the lateral sides of the wood skin, projecting lateral side edges are formed for overlapping engagement with rafters of the roof construction as described further hereinafter.
In forming a roof structure, a plurality of roof panels is employed. The size and shape of the panels is tailored to the roof structure to which they are to be fitted. The roofing panels are preferably conveniently sized for handling by one man. The roof structure further comprises rafters which support the roof panels. The roof panels are supported between pairs of rafters. The spacing of the rafters and their relative orientation depends on the configuration of the roof which is to be constructed. This in turn dictates the size and shape of the panels. The roofing panels and the rafters form a modular roofing system that is cut to size at a production location, usually off-site, and then transported to site to be erected.
A further feature of the roof panel comprises means for locating the panels relative to the rafters. The locating means preferably comprises pin means providing co-operating engagement between the panels and the rafters and more preferably still, between the integral beam of the roof panels and the rafters disposed to the opposite sides of the roof panels. The pin means cooperate with apertures therefor. In a preferred embodiment the apertures are formed in the rafters at the correct spacing to align with the pin means. The apertures are preferably preformed off-site at spacings to suite the size of the roof panels, it being preferred to have standardised sizes of panels wherever possible.
Alternatively, the apertures may be formed on-site, for example by drilling a hole in the rafters. The rafters are preferably metal box section elements and more preferably aluminium for considerations of lightness. The pin means preferably comprise sliding elements, preferably spring loaded, and received in apertures therefor formed in the integral beam.
Where the integral beam has an I-shaped cross-section, the central web has an aperture to receive the pin. Two pins are suitably provided. There is one to each lateral end of the integral beam disposed to project from the end thereof to engage with the hole in the adjacent rafter. The pins are preferably plastic.
The use of spring loaded pins may allow the panels to be quickly clipped into position and located relative to the rafters. The projecting lateral edges of the panels rest on the rafters and support the weight of the panels and any loading thereon. The integral beam supports the wood skin. The aforementioned arrangement of the location means may be reversed whereby projecting pin means is formed on the rafters and aperturing therefor is provided on the panel; say as a recess in the integral beam.
Additionally or alternatively, the structural beam of the roof panel may comprise one or more through apertures, or pilot holes, for receiving, in use, a mechanical fastener, such as a screw, nail or rivet. The through aperture, where provided, is suitably located so as to provide communication with a support rafter for the panel, or an adjacent panel. By such a configuration, the roof panel may be screwed, nailed or riveted to the support structure for the roof.
Another aspect of the invention provides a structural roof panel comprising a foam insulation layer and a skin of wood and further comprising means adapted for cooperation with a support rafter for the panel said means comprising at least one spring loaded pin means.
A yet further aspect of the invention combines the aforedescribed features and/or benefits of the invention with, or in, a structural roof panel comprising a foam insulation layer and a skin of wood and further comprising means adapted for cooperation with a support rafter for the panel said means comprising at least one spring loaded pin means.
Preferably two pin means are provided disposed to project from opposite sides of the roof panel to cooperate with a respective rafter. Preferably both pin means are spring loaded. More preferably the roof panel comprises an integral support beam with which the or each pin means co-operates engagingly.
The panel further comprises a lip means disposed on one longitudinal edge and projecting therefrom to engage with an adjacent roof panel. The lip means preferably comprises a channel or groove extending continuously across the width of the panel at least up to the rafters. The lip means may be a semi-flexible plastics extrusion having an arcuate cross-section. The lip means provides a means of anchoring that edge of the panel member to the rafter by way of the integral beam of the adjacent roof panel.
The roofing panel according to the invention has the advantage that it can be easily and quickly installed. This is particularly advantageous where the roofing panel is to be used in forming a replacement roof for a conservatory where ease and speed of installation is important.
The various aspects of the present invention will now be described further hereinafter, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view from underneath, one end and one side of a roofing panel according to the invention;
Figure 2 is an end view of the roofing panel of Figure 1;
Figure 3 is a detail of the support beam of Figure 2;
Figure 4 is a side view of the roofing panel of Figure 1;
Figure 5 is a perspective view of the roofing panel of figure 1 shown in relation to part of two rafters;
Figure 6 is a perspective view showing a detail of a roof panel and its means of connection with a rafter;
Figure 7 is a perspective view showing insertion of a second roofing panel; and
Figure 8 is a perspective view showing the roofing panel of Figures 1 to 5 installed on an eaves beam, with an additional insulation layer fitted.

Referring to the drawings, a structural roofing panel according to the invention 10 comprises a sheet of oriented strand board forming a wooden skin 12 having width and length defining opposite lateral edges 14, 16 and opposite longitudinal edges 18, 20, a face 22, which is uppermost in use as a roof panel 10, and an underside surface 24. Integral with the wooden skin 12 is a rigid cellular urethane foam layer 26 which is adhered to the underside 24 of the skin 12.
The insulation layer 26 has width and length defined by lateral sides 28, 30 and longitudinal edges 32, 34. The lateral edges 14, 16 of the wooden panel 12 project beyond the lateral sides 28, 30 of the insulating layer 26 to define oppositely projecting side flanges 36,38.
The panel 10 further comprises an integral structural beam 40, which, in the illustrated embodiment, is generally I-shaped in cross-section. It comprises an aluminium extrusion formed from an outer part 42 and an inner part 44 which are connected together by an elongate plastic rod 46. Each part 42, 44 has a central web defined by two spaced wall elements 47, 49. The two parts 46 and 48 are provided with mutually complimentary cup like formations 51, which each comprise pair of oppositely oriented arcuate limb portions 52, which engage with arcuately cross-sectioned recesses of the plastic rod 46. Likewise, the plastic rod 46 has two pairs of oppositely oriented arcuate limb portions 56, which engage with complementarily shaped arcuate recesses of the cup-like formations 50. Such a configuration enables the rod 46 to be slid lengthwise into engagement with the two opposing cup-like formations 50 to hold the outer 42 and inner 44 parts of the support beam 40 together. The rod floats, that is to say, it is free to slide longitudinally within, in the cup-like formations 50 of the extrusions and acts as a thermal break between the two parts 42, 44 as well as a structural interconnection therebetween.
The rod 46 extends width-wise across the width of the integrated beam 40, but terminates short of the ends of the beam 40. The beam 40 extends width-wise across roof panel 10 but terminates short of the lateral side edges 28, 30 with its ends substantially aligned with the lateral side edges28, 30 of the insulation layer 26.
Opposite ends of the cup formations 50 of the beam 40, not occupied by the rod 46, receive a respective axial compression spring (not shown) and a respective location pin 56, 58, also made of plastic. The springs bias the respective pins 57, 58 outwardly and allow them to be pushed inwardly for installation purposes as described further hereinafter.
In the illustrated embodiment the integral beam 40 is located immediately adjacent one longitudinal edge 18 of the panel 10 and abuts the foam layer 26. The illustration shows an air gap 60 between the beam 40 and the insulation layer 26, but in practice, the foam layer 26 may extend into, and optionally fill, this gap 60.
The respective longitudinal edges 32, 34 of the wooden skin 12 and the insulation layer 26 terminates in substantial alignment. An elongate sealing clip or lip 62 is appended to the longitudinal edge of the wooden skin 12 and/or the edge of the insulation layer 26 and extends across substantially the entire width of the panel 10. Its purpose is described further hereinafter.
Reference is now made to Figures 5 and 6, which show one structural roof panel 10 installed relative to two laterally spaced rafters 70, 72 (only part of which are illustrated). The illustrated rafters 70, 72 are aluminium box section members and the side walls thereof have holes 74 formed in them at prescribed spacings to receive the aforementioned locating pins 57, 58. It will also be noted that the oppositely projecting side flanges 36, 38 of the roof panel 10 rest on the upper surfaces of the rafters 70, 72 thereby supporting the roof panels 10, whilst the integral beam 40 provides rigidity to the wooden panel 10.
Figure 7 shows a second roofing panel 100 being introduced into position. The lower most part of the sides of the insulating layer are introduced between the rafters 70, 72 and the elongate sealing clip/lip 62 introduced under the outer flange of the integral beam 40 of the panel that 10 has already been installed to provide a water tight connection, in conjunction with a mastic or silicone sealant applied to the lip 62 if required, and to physically link the lower edge of the second panel 100 with the structural beam 40 of the first panel 10. This inhibits lifting of the lower edge of the second panel 100. Thereafter the second panel 100 is pivoted into full engagement with the rafters 70, 72 and the respective spring pins 570, 580 engaged in the respective reception holes 74 to locate the panel 100 with respect to the rafters 70, 72.
Thus it will be seen that assembly of the structural panels 10, 100 is particularly straightforward and, if necessary, can be achieved by one man operating from a ladder or suitable work platform.
In order to facilitate rapid erection of a roof structure utilising the aforedescribed roof panels 10, 100, the sizes of the rafters 70, 72 required to support the panels 10, 100 and the sizes and shapes of the roof panels themselves are determined from the size of the existing wall structure following, for example, a site visit or from accurate design drawings. The components can then be manufactured off-site to the required size enabling the components to be delivered to the site as a module of correctly sized parts ready for assembly.
In Figure 8, it can be seen that the roofing panel 10 has been fitted to an eaves beam 80 of an underlying building structure (not shown). As can be seen, the wooden skin 12 rests on top of the eaves beam 80 and is affixed thereto at intervals, for example, using self-tapping screws (not shown) that engage with a recess 82 of the eaves beam 80. The wooden skin 12 projects beyond the eaves beam 80 and is fitted with an end assembly 84, to which soffits/fascias can be affixed to conceal the roof/eaves intersection and to provide a weatherproof and visually appealing façade for the roof edge.
In order that the roof can be classified as a "warm roof", an additional layer of foam insulation material 86 is affixed on top of the wooden skin 12, which insulation layer 86 is overlaid with a waterproof breather membrane 88. A warm roof, advantageously, does not require ventilation.
It will be appreciated from the foregoing description that the construction of a complete roof structure will require a plurality of structural roof panels and a plurality of supporting rafters and that whilst the finished assembly is largely bespoke it will nevertheless be comprised of a number of components that are identical, e.g. a lot of the roof panels will be the same size and the overall construction will aim to use standardised sizes where possible. The creation of flat sloping roofs will primarily utilise roofing panels that are oblong except where sloping roofs and the rafters therefor converge and require panels that have tapered lateral sides. Nevertheless it is readily possible to manufacture the roofing panels according to the invention in the required shapes.
In forming a completed roof structure of traditional appearance a breather membrane is installed over the wooden skin of the assembled roof panels which is then overlaid with battens and tiles. Plasterboard can be installed inside for example by fixing to the underside of the rafters. The lowermost panels sit on top of and project beyond, the eaves beams. Soffits and fascias can be added later. The lowermost panels have a groove cut in them into which the eaves beam rests. Screws affix the wood of the panels to the eaves beam.
The invention is not restricted to the details of the foregoing embodiments, which are merely exemplary of the invention. For example, the materials of manufacture, the relative dimensions of the components, the shape of the cross-sections, etc., can all be varied without departing from the scope of the invention.

Claims

A structural roof panel (10) comprising a single skin of wood (12) having a foam insulation layer (26) on at least part of one face and further comprising at least one structural beam (40) formed integrally therewith.
A structural panel (10) as claimed in claim 1 in which the wood skin (12) has lateral side edges (14, 16) that project beyond lateral side edges (28, 30) of the foam insulation layer (28).
A structural panel (10) as claimed in claim 1 or 2 in which the integral beam (40) comprises an aluminium beam extending width-wise of the panel (10) and is attached to said one face of the wood skin (12).
A structural panel (10) as claimed in claim 1, 2 or 3 in which opposite ends of the integral beam (40) terminate short of lateral side edges (14, 16) of the panel (10) as defined by lateral side edges (14, 16) of the wood skin (12).
A structural panel (10) as claimed in claim 3 or 4 in which the integral beam (40) comprises inner (44) and outer parts (42) interconnected by an insulating elongate rod (46).
A structural panel (10) as claimed in any of claims 1 to 5 and further comprising a clip element (62) disposed along a longitudinal edge (20) of the panel (12) for co-operating engagement with another roof panel (10) when used in a roof structure.
A structural panel (10) as claimed in any one of the preceding claims and further comprising laterally disposed panel location means (56).
A structural panel (10) as claimed in claim 7 in which the panel location means (56) comprises at least one slideable spring loaded pin (57, 58).
A structural roof panel (10) comprising a foam insulation layer (40) and a skin of wood (12) and further comprising means (56) adapted for cooperation with a support rafter (70, 72) for the panel (10) said means comprising at least one spring loaded pin means (57, 58).
A structural roof panel (10) according to any of claims 1 to 8, comprising a foam insulation layer (40) and a skin of wood (12) and further comprising means (56) adapted for cooperation with a support rafter (70, 72) for the panel (10) said means comprising at least one spring loaded pin means (57, 58).
A structural panel (10) as claimed in any of claims to 10 in which two said pins (57, 58) are provided, one to each lateral side (14, 16) of the panel (10).
A structural roof panel (10) according to any preceding claim, further comprising a layer of insulation material located above, in use, the wooden skin (12).
A structural roof panel (10) according to any preceding claim, further comprising a waterproof breather membrane located above, in use, the wooden skin (12) or the layer of insulation material.
A structural roof panel (10) according to any preceding claim, further comprising an eaves assembly (80) to which, in use, a soffit and/or a fascia can be affixed to conceal the roof/eaves intersection.
A structural roof panel (10) according to any preceding claim, wherein the structural beam (40) comprises at least one through aperture for receiving, in use, a mechanical fastener from the group comprising: a screw; a nail; and a rivet, the through aperture being located so as to provide communication with a support rafter (70, 72) for the panel (10), or an adjacent panel (10).