Self aligning three dimensional support structure for a roof constructed with prefabricated components
The invention provides a method for easy prefabrication of a self aligning three dimensional roof support and roof structure, such as a dormer or porch roof, which is fully constructed of sheet goods with tab and slot interconnecting components. The roof support structure is constructed of a parallel aligned space series of substantially rigid sheet truss members and a parallel aligned space series of substantially rigid purlin members running perpendicular to the truss members and interlocked with the truss members with opposing interlocking slots to form a self- aligning three dimensional support structure whereby the flush upper sheet ends provide support for roof sheathing. The roof sheathing and additional side fascia members are fit to the substructure with inter-engaging tabs and slots.
The present invention pertains to support structures, and more particularly to a self aligning three dimensional support structure for a roof, such as a dormer or a porch roof, which is constructed of prefabricated components.
BACKGROUND OF THE INVENTIONThe conventional construction problem encountered for detailed porch roofs and dormers is that they are labor intensive, especially if they include curves. Conventional stick frame construction also involves expensive lumber, heavy weight, waste of materials, and expansion and contraction issues.
It is a principal object of the present invention to construct tradition style porch roofs and dormers with high efficiency.
SUMMARY OF THE INVENTIONThe three dimensional support structure for a roof of the present invention is constructed of prefabricated components, which, when assembled, are self aligning to efficiently provide a dormer or a porch roof The support structure of the present invention is comprised of a parallel aligned spaced series of substantially rigid sheet truss members, and a parallel aligned spaced series of substantially rigid sheet purlin members running perpendicular to the truss members and interlocked with the truss members with opposing inter-engaging slots to form a self aligning three dimensional support structure with flush upper sheet edges for supporting roof sheathing. The substantially rigid sheet material used for constructing the components can be common laminated plywood, or other wood sheet goods, with trim components constructed of weather impervious material, such as PVC sheet goods.
The basic substructure just described will also include substantially rigid sheet end truss members inter-engaged at right angles to outside opposite ends of the purlin members with intermeshing tabs and slots. To further complete the sub support structure, substantially rigid sheet fascia members are provided and inter-engaged at right angles with opposite outside ends of the truss members with intermeshing tabs and slots. Then substantially rigid roof sheathing, which is also precut, covers the upper edges of the support members with intermeshing tabs and slots. The truss members may form a conventional center ridge peak.
Exterior exposed surfaces of this substructure are then preferably covered with precut weather impervious sheet material, such as PVC sheet goods. For additional strength selected inter-engaging connections between the sheet members and between the sheet members, and the roof sheathing, may be secured with fasteners or glue.
The unique roof support structure of the present invention provides the convenient opportunity for manufacturing all of the sheet good structure members and roof sheathing to be cut to appropriate size, shape and dimension with a preprogrammed CNC router machine. The machine is programmed whereby a minimum of only projection, width, and height to ridge dimensions are required to be input into the CNC router in order to provide production of all the prefabricated parts or components, with slots and tabs as required, for shipping and assembly of the support structure.
The prefabricated component roof support structure of the present invention provides many advantages over conventional stick frame construction. The system of the present invention provides extreme labor savings, affordable shipping and packaging in component form, low skill level for assembly, and limitation in variation of the types of materials required to construct the structure since it is produced primarily from sheet goods, which in addition, permits the utilization of CNC machinery for fabrication.
The ultimate construction is also stronger than conventional framing, light weight and the tab and slot construction provides self-alignment of the structure. The use of a tape measurer is not even required to frame the unit.
Other objects and advantages hereinafter in the following description and claims. The accompanying drawings show, for the purpose of exemplification, without limiting the scope of the invention or the appended claims, certain practical embodiments of the present invention wherein:
A completed embodiment of a porch roof structure manufactured with tab and slot self aligning three dimensional construction in accordance with the teachings of this present invention is illustrated in
The porch roof structure 10 is constructed fully of sheet goods, such as plywood, for the subassembly and weather impervious PVC sheet goods for the exposed trim, by the utilization of a CNC router machine and the use of computer spread sheets for the variables. As is illustrated in
The CNC machine then automatically cuts all the sheet components for the sub-framing or subassembly as illustrated in
The subassembly framing is all constructed of sheet goods, such as plywood, and includes three to five truss members depending upon the projection dimension A, two sub-rake members 14, two roof sheathing members 15, two sub-fascia members 16, two sub-beam side members 17 and seven purlin members 18. Each of these members is cut by the CNC machine with protruding tabs 20 and with corresponding receiving slots 21 which do not change in size throughout the entire sub framing.
The key shown in
Because a router bit does not cut square corners, but instead cuts round corners, the CNC router is programmed to cut all inside corners of tabs and slots open so that there is a complete inter fit between all tabs 20 and slots 21 as is illustrated in
The subassembly 24 of all the framing components illustrated in
The utilization of laminated plywood of one sheet size to do all structural components minimizes the quantity of material required to be maintained in stock.
Turning next to
Some of these members are also provided with dados 31 as a decorative feature. When all members are assembled, the complete porch roof product appears as illustrated in
In the event that the porch roof or dormer is wider than standard sheet goods, two pieces of sheet goods may be engaged and interlocked with each other to provide a longer continuous piece for fabrication of the subassembly components of the present invention. For example, two sheets of plywood may be joined with an interlocking seam as by dovetail or bow tie jointing and thereafter applying a gusset to the joint thereby providing doubling of the basic sheet size to be incorporated into the structure. This principal may also be taken advantage of for the purposes of shipping, thereby maintaining the largest product to be no larger than a standard size sheet of plywood.
The exterior finish parts are components as illustrated in
The ceiling portion of the porch structure 10 can be protected with wood boards or paneling which provides an authentic tongue and groove bead board look or the like to close it in and provide an authentic finished appearance.
Claims
1. A prefabricated self aligning three dimensional support structure for a roof, such as a dormer or a porch roof, the support structure comprising:
- a parallel aligned spaced series of substantially rigid sheet truss members;
- a parallel aligned spaced series of substantially rigid sheet purlin members running perpendicular to said truss members and interlocked with said truss members with opposing inter-engaging slots to form a self aligning three dimensioned support structure with flush upper sheet edges for supporting roof sheathing.
2. The support structure of claim 1, including substantially rigid sheet end truss members inter-engaged at right angles with opposite ends of said purlin members with intermeshing tabs and slots.
3. The support structure of claim 2, including substantially rigid sheet fascia members inter-engage at right angles with opposite ends of said truss members with intermeshing tabs and slots.
4. The support structure of claim 3, including substantially rigid roof sheathing covering and inter-engaging upper edges of said members with intermeshing tabs and slots.
5. The support structure of claim 4, wherein upper edges of said truss members form a center ridge peak.
6. The support structure of claim 4, wherein selected exterior exposed surfaces of said structure are covered with weather impervious sheet material.
7. The support structure of claim 4, wherein selected inter-engaging connections between said members, and between said members and said sheathing, are secured with fasteners or glue.
8. The support structure of claim 4, wherein said members and said sheathing are cut to appropriate size, shape and dimension with a preprogrammed CNC router programmed whereby a minimum of only projection, width and height to ridge dimensions need be input into said CNC router to provide production of all the prefabricated parts, with slots and tabs as required, for assembly of the structure.
9. The support structure of claim 4, wherein said substantially rigid sheet members are comprised of plywood.
10. The support structure of claim 9, wherein said sheathing is comprised of plywood.
Type: Application
Filed: Jun 15, 2006
Publication Date: Dec 20, 2007
Inventor: Robert P. Viviano (McKees Rocks, PA)
Application Number: 11/453,657
International Classification: E04F 13/04 (20060101);