Patent Application
20090277113
The present invention relates generally to building structure and in particular, to a structural insulating panel and flat roof structure employing the same.
Historically, flat or horizontal roofs on commercial and residential buildings have been common in warmer, drier climates where water accumulation as a result of precipitation is not a problem. More recently, flat roofs have become popular in cooler, wetter climates. Unlike sloped roofs, flat roofs have ineffective drainage characteristics making them prone to leakage problems. In wetter climates, to deal with this drainage issue, complex water proofing is typically required in flat roofs. In commercial buildings, drains are sometimes provided in the flat roofs to collect rainwater and melting snow and direct the water off of the roofs.
For example, U.S. Pat. No. 5,144,782 to Paquette et al. discloses a draining system for water which may collect between the upper and lower membranes of a flat insulated roof. Insulating panels located between the upper and lower membranes are provided at both their upper and lower faces with a network of intersecting grooves. The networks of grooves communicate with each other through passages made through the insulating panels or constituted at the insulating panel joints. The grooves and passages provide drainage channels for any water that has seeped under the upper membrane as a result of perforations in the upper membrane. A lower drain is sealed to and opens above the lower membrane to drain water collected by the drainage channels. Drainage of the water helps to prevent deterioration of the insulating panels and water accumulation which may provoke overload problems.
Although such drainage structures are effective in removing water from flat roofs, they add significant complexity to the building structures and hence, increase costs making them unsuitable in many environments. As will be appreciated, alternative techniques to improve drainage in flat roofs are desired.
It is therefore an object of the present invention at least to provide a novel structural insulating panel and roof structure employing the same.
Accordingly, in one aspect there is provided a structural insulating panel for use in a flat roof structure comprising upper and lower structural layers and an intermediate layer between said upper and lower structural layers, the intermediate layer being shaped such that said upper structural layer is sloped relative to a horizontal plane when said structural insulating panel is installed in a flat roof structure.
In one embodiment, the intermediate layer is shaped such that the upper structural layer is sloped in multiple dimensions relative to the horizontal plane. The upper structural layer may slope generally linearly downwardly in generally orthogonal directions or may curve downwardly in different directions. In another embodiment, the intermediate layer is shaped such that the upper structural layer slopes generally linearly downwardly in a single direction.
In one form, the intermediate layer is sandwiched directly between the upper and lower structural layers. The thicknesses of the upper and lower structural layers are selected to give the structural insulating panel a desired fire rating. Each of the upper and lower structural layers may have a thickness in the range from about ⅛″ to about 1⅛″. The intermediate layer may have a minimum thickness of about 1″ and a maximum thickness of about 16″.
According to another aspect there is provided a flat roof structure comprising a plurality of abutting structural insulating panels, each structural insulating panel spanning at least a pair of adjacent rafters of the flat roof structure and defining an upper decking surface on which roofing is applied, the structural insulating panels being configured such that the upper decking surface is non-horizontal thereby to promote drainage.
The structural insulating panels in one form are arranged at least one of end-to-end and side-to-side with adjacent structural panels carrying mating formations. Sealant seals seams between the adjacent structural insulating panels.
According to yet another aspect there is provided a structural insulating panel comprising an intermediate layer sandwiched between and adhered to first and second structural layers, the intermediate layer varying in thickness such that the first and second structural layers are non-parallel.
Embodiments will now be described more fully with reference to the accompanying drawings in which:
Turning now to
The upper surfaces 36 of the structural insulating panels 32 define the decking 38 of the flat roof structure 30 on which roofing (not shown) is applied. The structural insulating panels 32 are configured so that the decking 38 is pitched in multiple dimensions thereby to promote drainage towards the outer peripheral edges of the flat roof structure 30. The pitch in each dimension is typically selected so that it does not exceed 1/12″. In the embodiment of
Turning now to
The core 70 varies in thickness to give the structural insulating panel 32 its desired pitch. As a result, the upper structural layer 62 which overlies the top skin 72 of the intermediate layer 60 conforms to the orientation of the intermediate layer and thus, provides the sloped upper decking surface onto which the roofing is applied. One side edge of the lower structural layer 64 has a groove 80 formed therein and the opposite side edge of the lower structural layer 64 has a tongue 82 formed thereon. The groove 80 is shaped to receive a tongue formed on an adjacent structural insulating panel 32 and the tongue 82 is shaped to be inserted into the groove formed in another adjacent structural insulating panel 32.
Looking back to
In the above embodiment, the structural insulating panels 32 of the flat roof structure 30 are configured so that the flat roof structure 30 slopes linearly downward in two different directions. Those of skill in the art will appreciate however, that other structural insulating panel configurations can be used in flat roof structures 30 to promote drainage. For example, turning now to
Although the embodiments described and shown above show adjacent structural insulating panels 32 as comprising mating formations in the form of tongues and grooves, those of skill in the art will appreciate that alternative joints between adjacent structural insulating panels can be used. For example,
Although dimensions for the structural insulating panels and components therefor, are provided above, those of skill in the art will appreciate that the dimensional information is exemplary. Depending on the environment in which the structural insulating panels are being deployed, the overall dimensions of the structural insulating panels and the dimensions of the panel components may vary from those discussed above.
In the embodiments described above, the upper and lower structural layers 62 and 64 are described as being formed of plywood. Those of skill in the art will appreciate that the upper and lower structural layers may be formed of other suitable structural material such as for example OSB, metal sheet, fire resistant board etc. Also, the intermediate layer 60 need not be formed of EPS. Other foam material such as for example urethane foam, polyurethane foam, isocyanurate foam etc. or other suitable non-foam material such as for example honeycomb board may be used.
While particular examples of structural insulating panels that provide pitched upper decking surfaces are described and illustrated above, those of skill in the art will appreciate that the structural insulating panels may take on other orientations to promote drainage. Of course, if desired the structural insulating panels can be used on wall structures for structural and/or decorative purposes.
Although embodiments have been described above with reference to the drawings, those of skill in the art will appreciate that variations and modifications may be made without departing from the spirit and scope thereof as defined by the appended claims.
