US 3262239 A
Description (OCR text may contain errors)
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LAMINATED WOOD BUILDING UNIT Filed Aug. 27, 1962 5 Sheets-Sheet 5 IWN TOR. $04445 M245 Y United States Patent 3,262,239 LAMINATED WOOD BUHLDING UNIT Thomas W. Mills, 31 Sweg Bay Road, Portuguese Bend,
alif. Filed Aug. 27, 1962, Ser. No. 219,381 1 Claim. (Cl. 52540) This invention relates to roofing construction and more particularly to a building unit for roofing, sliding, sidewalls, curtain walls, other walls and/ or any other wooden frame building facing unit which is comprised of combined sheathing and shingles and is constructed in a manner to provide an installation which is relatively inexpensive in manufacturing cost and more efficient and more easily installed than the constructions and methods heretofore proposed.
There are at present many types of roofing construction employing shingles which use in general somewhat the same construction techniques. In addition to the shingle roof, there are also several other types of roofing construction such as the so-called rock roof and a fairly new innovation which utilizes end matched tongue and groove construction. In addition, either used separately or integrally with other types of construction is a socalled prepared roofing, that is to say roofing composed of a fabric, prepared and usually saturated with a waterproofing compound in the factory, and sold in rolls or in sheets to be applied over wooden sheathing. Such roofing, which is quite commonplace, is often made of asbestos or other fibrous material, is generally saturated with tar or asphaltic composition and frequently given an outer waterproofing surface of the same character which, being black, absorbs heat from the suns rays.
The present invention is an improvement over all types of roofing construction although its advantages are more clearly apparent when considered in conjunction with the present construction techniques used to fabricate and assemble the so-called shingle roof. Shingle roofs can be classified into at least three separate categories. The first is composed of composition shingles, the second wood shingles and the third shake shingles which vary in thickness from piece to piece, the average thickness of the pieces depending upon the quality of material used. The construction techniques utilized in all three of these varieties is basically the same and must be understood to appreciate the deficiencies the present invention eliminates.
It should be understood that shingle roofing can be used in construction such as houses where the walls may be composed of load bearing studs or in many other constructions which may have bearing or non bearing walls such as post and beam construction, certain modular walls and in fact anywhere a shingle roof may be considered desirable, the only prerequisite being adequate supporting structure. In present practice the supporting structure of the building is completed up to and including the rafters. Before installing the shingles, the construction workers lay sheathing material over the rafters. Sheathing is normally comprised of material such as one by three or one by four pieces and is laid lengthwise across the rafters. In certain cases, such as in the utilization of the composition shingle, it is customary for the sheathing material to completely cover the rafters, while in construction utilizing the shake shingle, it is often possible to use sheathing material which is alternately open spaced. In this latter construction, a one by three or one by four piece is first laid lengthwise across the rafters by nailing at appropriate places. A second sheathing plank is then laid adjacent the first piece and a third piece adjacent the second. The third piece is then nailed to the rafters and the intermediate piece is azaazaa Patented July 26, 1966 then picked up and placed adjacent the third piece on the opposite side thus leaving a space between the first and third sheathing plank. This same procedure is repeated until the entire rafter area is covered by alternate planks of sheathing. Whether the shingle be composition, wood or shake and whether the sheathing be solid or alternately space, there can then be utilized some form of matting material which can be placed over the sheathing or if desired the matting can be used over the first shingle course. The shingles are then nailed to the sheathing and the roof is considered as final construction.
It should be noted by the above description that the amount of time and effort required is substantial. It is necessary to firmly nail the sheathing material to the rafters and then in turn to nail individually each of the shingles. Shingles are customarily nailed with corrosion-resistant nails of suflicient length to penetrate the sheathing, using two nails for shingles up to eight inches in width and three nails for shingles of wider dimension. The number of nails used and the man hours consumed in such an operation are substantial and make this type of roof construction extremely expensive although in cer tain sections of the country it is popular and fairly extensively used.
The present invention is directed toward a new and improved roofing construction to eliminate the time and effort involved in fabricating, assembling and constructing roofing of the type just described. It consists of providing the sheathing and shingles in a single unitary building unit which can be nailed or otherwise secured to the supporting members such as the rafters and the invention further contemplates the application of a plurality of similarly formed units to the'rafters in such a manner that portions of one unit will overlap portions of the next adjacent unit to produce closed joints between said units. Further the unit may be provided in suitable widths and in various lengths to appreciably reduce the time and cost involved in roof construction. In the preferred embodiment the unit employs shingles with the grain running parallel to the direction of the rafters and perpendicular to the center supporting ridge. As will be obvious from the description hereinafter presented, this provides a unit with unusually efficacious and desirable construction qualities.
In constructing the unit it is customary to manufacture the sheathing portion and the shingle portion separately. These separate portions are then cemented, adhered, or otherwise secured together to form the completed laminated unit of sheathing and shingles. If it is not desired in a particular construction to have the shingle wood grain parallel to the rafters, the entire unit may be formed from a single piece of material and the lamination just above mentioned thereby avoided although, from a manufacturing standpoint and in the interest of economy and good construction it is more desirable to preform the sheathing as well as the shingle portions and join them together to make the laminated unit.
Regardless of whet-her the sheathing and shingle portions are laminated or not, the shingle portion will be offset relative to the sheathing portion so as to provide a nailing surface or area on one transverse side of the sheathing portion. In addition in the preferred embodiment a nailing surface or area is provided on one longitudinal side of the shingle portion while in another embodiment the shingle portion is offset relative to the sheathing portion so as to provide a nailing sur face or area on one longitudinal side of the sheathing portion. In all embodiments when the units are installed both nailing areas are covered by the respective opposite transverse and longitudinal sides of the shingle portions of the next adjacent units, whereby all nailing or other means of securement to the rafters will ultimately be concealed and certain edges of a unit will be so formed as to provide interlocking relation with certain edges of the next adjacent unit. Such overlap also provides a waterproof roof construction and as will be hereinafter described a construction which if desired will provide a shingle construction with grain lying in the direction of water flow. To further simulate shingle construction and also to gain additional strength, it is desirable to score the shingle portion in a manner to be hereinafter described.
Other features and advantages of the present invention will be apparent from the following description taken in connection with the accompanying drawing in which:
FIGURE 1 is a perspective exploded view of several building units made in accordance with this invention and shown in proper corresponding relationship just before they are assembled and applied to the rafters as part of the final roof construction;
FIGURE 2 is a perspective view of the parts shown in FIGURE 1 assembled in proper overlapping relationship;
FIGURE 3 is a horizontal sectional view of the parts shown in FIGURE 2 taken on line 3-3 thereof and looking in the direction of the arrow;
FIGURE 4 is a vertical sectional view taken as on line 44 of FIGURE 2 and looking in the direction of the arrow;
FIGURE 5 is an end elevational view of a single unit showing a treatment of the exposed surface thereof;
FIGURE 6 is a vertical sectional view of a single unit to illustrate a different treatment thereof;
FIGURE 7 is an end elevational view of a single unit showing a modified construction of the unit of the present invention;
FIGURE 8 is a fragmentary perspective view showing a portion of the roofing of the present invention applied across the rafters of a house under construction;
FIGURE 9 is a schematic representation of the method used to produce the shingle portion of the building unit in a manner which will permit the shingle grain to run in the direction of water fiow from the roof, that is in a direction parallel to the rafters and perpendicular to the center supporting ridge;
FIGURE 10 is a fragmentary perspective view showing the finger joint which is used to secure the pieces of the shingle portion when the process of FIGURE 9 is utilized;
FIGURE 11 is an exploded perspective view of another embodiment of the building unit of the present invention showing the sheathing and shingle portions and the offset pattern and further showing the grain of the shingle portion running parallel to the direction of the rafters and scoring placed at appropriate points;
FIGURE 12 is an exploded perspective view of another embodiment of the building unit of the present invention showing the sheathing and shingle portions and the offset pattern and further showing the grain of the shingle portion running parallel to the direction of the rafters and scoring placed at appropriate points;
FIGURE 13 is a fragmentary perspective view of a portion of the machinery and process used to form shingle portions of building units with the grain running parallel to the direction of the rafters;
FIGURE 14 is another portion of the machinery depicted in schematic diagram in FIGURE 9 and which serves to produce the end grain shingle construction; and
FIGURE 15 is another portion of the machinery depicted in schematic diagram in FIGURE 9 and which assists in producing shingle portions of the building unit of the present invention with the grain running parallel to the transverse edge of the unit.
Referring now to the drawing and particularly to FIGURES 1, 2, and 8 thereof, there is shown the roofing construction in an exploded view with the individual units spaced to more clearly show their cooperating relationship and the construction as finally assembled and affixed to the rafters. In general, as is shown clearly in FIGURES 1 and 2 of the drawing each unit consists of a base or sheathing member 12 and an overlapping or shingle member :13. As depicted the pieces are overlapped so that when assembled the construction will be completely impervious to water and the elements. As indicated by the terminology the base member 12 corresponds generally to the sheathing material utilized in standard construction and the outer or overlapped member 13 attached to the base member 12 corresponds generally to the shingle utilized in standard construction techniques.
Referring again to the drawings and particularly to FIGURES 1, .2, 3 and 4 thereof, there is indicated generally the shingle portion 13 and the sheathing portion 12 of units made in accordance with one embodiment of the present invention, the shingle portion having a lip, trailing edge, or overhang portion 14 which extends beyond the longitudinal edge 15 of the underlying sheathing. Further the sheathing has a transverse edge 17 which extends beyond the transverse edge 18 of the overlying shingle portion. All of the longitudinal edges of the sheathing portion and the shingle portion are substantially parallel to each other, as are also all of the transverse edges of said portions, the entire unit being substantially rectangular.
The longitudinal upper edge 19 of the shingle portion is shown rounded nose and substantially flush with the longitudinal upper edge 20 of the sheathing material and the opposite or bottom longitudinal edge 22 of the shingle portion is provided with an inclined upsweep shapered or routed-groove, or kerf, 23, to provide a bottom receiving-portion 23, said receiving-portion adapted to receive therein the upper "longitudinal edge 19 of the shingle portion of the next adjacent unit, all as clearly indicated in FIGURE 4 of the drawing.
The upper longitudinal edge of the sheathing portion 20 is shown in tongue construction 19, adapted to fit into a kerf 23 although as will be hereinafter discussed it is possible to use a lap joint or to square cut, bevel or round this edge if it is deemed desirable the only essential being that it be flush with the mating edge of the next adjacent unit when installed. The mating edge or bottom longitudinal edge 15 of the sheathing portion is shown in such mating configuration. Thus it will be understood that when two adjacent units are interfitted With each other as shown in FIGURE 4 the lower edge 15 of the sheathing portion will fit and mate with the upper edge 20 of its mating unit and that the shingle edge portion 19 of the lower unit will fit within the receiving slot 23 of the unit thereabove.
The horizontal joint between two adjacent units is important since it provides a means for preventing displacement of the adjoining longitudinal edges of the adjacent units between the rafters such as 24. In other words, the usual practice in building construction is to space the rafters on centerings whereby there is a relatively considerable span between two adjacent rafters which is bridged by the units forming the subject matter of this invention. Centering distances may vary from two feet when using one inch sheathing to twenty feet or more in the case of five inch sheathing. The centering distance also depends upon the roof load and may be seven and one-half feet in the case of two inch sheathing, twelve feet in the case of three inch sheathing and sixteen to eighteen feet in the case of four inch sheathing. Since the units constitute the exposed portion of the roof, said units are subjected to the elements such as Wind and weather and therefore might have a tendency to flex or warp in the span between the rafters. Therefore unless the longitudinal edges of the adjacent tiers or courses are tightly fitted together, there might result a separation therebetween to disrupt the continuity of the roof and allow the elements to enter or pass through the longitudinal joint. As was pointed out such a fit can be achieved with square cut, bevel, lap joint or tongue and groove edge construction. It has also proven efficacious to use the fastener described in my copending application Serial No. 157,621, filed December 5, 1961 and now abandoned.
As shown in FIGURE 3, the transverse edges or ends 17 and of the sheathing portion of each unit are tongue and groove. It should be understood that the transverse edges may also be lap joint, square cut or beveled. By utilizing the fastener described in my copending application Serial No. 157,62, filed December 5, 1961, it is possible to provide an interlocking effect in the vertical joint between two adjacent units. If such a fastener were not available, it would be necessary, to insure a firm construction, to make certain that the lengths of the units were made such as to be equal to the spacing of the rafters, or equal to a multiple thereof so that the transverse or vertical joints between adjacent units would lie upon a rafter as clearly indicated in FIGURE 3 of the drawing, the transverse dimension of a unit being made as desired. The transverse edges of the shingle portion of each unit may likewise be tongue and groove although this is not necessary since a rectangular edge as shown in FIGURES 1 and 2 may be sufficient in view of the fact that the said transverse edges need only have abutting relation with each other because the joint formed by said edges overlies a solid portion of the sheathing material.
The outer exposed surface 27 of the shingle portion of the unit is preferably in a plane which is oblique to the plane of the rear sheathing portion to give the usual appearance of shingles when completed.
In applying the units to the rafters, as depicted in FIGURE 2 of the drawing, nails such as indicated at 28 are driven through the projecting nailing areas 29 of the sheathing portions and the nailing areas 30 of the shingle portions into the rafters, and then the next adjacent units are applied so that the projecting parts of the shingle portions of the next adjacent units will overlie the nailing areas of the units that have been secured to the rafters, thereby concealing the nails and protecting the heads thereof from the weather.
The units may be variably formed. In other words they may be fashioned as shown in the drawings and described hereinbefore, or they may be modified somewhat While still incorporating and retaining the general salient principles of the invention.
For example, the embodiment of the invention depicted in FIGURES 1 and 2 has been shown and described with the sheathing portion of the unit offset from the shingle portion along one transverse edge. Such a construction as has been pointed out provides a transverse nailing area on the sheathing portion and a longitudinal nailing area on the shingle portion of the building unit. In the embodiment of the invention depicted in FIGURE 11 of the drawing there is indicated generally an additional configuration of the invention, the shingle portion 32 having a longitudinal edge 33 and a transverse edge 34 which extends beyond respectively the longitudinal edge 35 and the transverse edge 37 of the underlying sheathing portion 38. Further the sheathing portion 38 has a longitudinal edge 39 and a transverse edge 40 which extend beyond respectively the longitudinal edge 42 and the transverse edge 43 of the overlying shingle portion 32. As should be evident from the drawing and description, there is thus provided a building unit with the nailing strips on both transverse and longitudinal edges being situated in the sheathing portion of the building unit.
In the embodiment of the invention depicted in FIG- URE 12, there is shown an offset pattern somewhat similar to that depicted in FIGURE 11 but with the longitudinal nailing strip being situated on the opposite side of the sheathing portion 45 of the building unit.
Further the material from which the building unit is formed may be of various kinds. The sheathing portion may be of a material different from the material of the shingle portion whereby, for example, it would be possible to have the sheathing portion made of a material particularly suitable as an insulation of temperature and noise, and the shingle portion could be of a material particularly adapted to resist weather, in which case the sheathing portion would preferably be laminated with the shingle portion. On the other hand, the sheathing portion and the shingle portion could be of the same material, the shingle portion being treated in a manner different from the sheathing portion; as an illustration it may be mentioned that the unit as a whole might be formed of fibrous material with the shingle portion surface-treated and/or impregnated to make it highly resistant to Weather while leaving the sheathing portion in its original fibrous condition as well suited for insulation against temperature and noise. A preferred material is wood fiber insulating board because of its lightweight, high insulating value, and adaptability for receiving most any treatment and finish.
In FIGURE 6 there has been illustrated a construction wherein the unit has been dipped or submerged in a solution which has penetrated or impregnated the material of the unit, as indicated by the stippling 47, to provide complete saturation or impregnation of the shingle portion along its longitudinal and transverse edges in order to stiffen the same as well as to protect the exposed surfaces thereof, but leaving the central part or core 48 of the unit unsaturated and/or unimpregnated in order not to impair the insulating quality of the unit. As an example of such a solution there may be mentioned hot asphalt or other bituminous substance which not only stiifens the treated parts of the unit but additionally renders them waterproof or moisture repellant.
On the other hand coatings of paint or other substance may be applied to some or all of the surfaces of a unit, and in FIGURE 5 there has been illustrated a coating 49 of finely divided material such as sand, slag, mica, rock or other suitable grit-like or rock-like finishing material, which coating has been applied only to that portion of the shingle which will be exposed to view or to the elements, said coating being adhered in any suitable manner to the material of the unit.
In FIGURE 7 of the drawing there is shown an additional configuration of the invention wherein the sheathing portion 50 is depicted with an inclined upper face 52 and substantially rectangularly shaped shingle portion 53.
It is obvious that those skilled in the art may vary the details of construction and arrangements of parts without departing from the spirit of this invention and therefore it is desired not to be limited to the exact foregoing disclosure except as may be required by the claim.
As has been mentioned, it is desirable for purposes of aesthetic qualities and strength to simulate as closely as possible normal shingle construction. In the case of using materials which are available, the building unit would result in a construction with the grain of the wood forming the shingle portion of the unit running in a longitudinal direction parallel to the center supporting ridge and at right angles to the rafters and direction of water flow. The present invention incorporates a process for producing shingle portions of the building unit with the grain running at right angles to the center supporting ridge. When the shingle portion is scored at intervals approximating the width of normal shingles, the roof cannot be visually detected as different from normal shingle construction. To make such a unit the procedure is as shown schematically in FIGURE 9 and as further ampli- 7 fied by the machinery depicted in FIGURES 13, 14 and 15.
The manufacture is accomplished by first gluing together short and narrow pieces of clear lumber to produce finish grades in the exact sizes required for a specific building unit. It is possible to use almost any kind of wood although Douglas fir, hemlock and western red cedar are preferred.
The method used consists in first cutting out the clear sections found between knots and defects of certain types of lumber. These short, clear sections are run through a finger joint machine which as shown in FIGURE of the drawing cuts fingers 54 in one end and grooves 55 in the other end. As the pieces with the fingers and grooves leave the machine a glue wheel applies adhesive to the grooves.
A roll press operator then places the pieces from the jointer onto a moving belt which carries them into the roll press. As is depicted clearly in FIGURE 15, the finger joints are pushed together by the press rolls. The first pair of rolls 57 runs faster than the next pair 58 which forces the joint 59 tightly together, forming a continuous board, which passes into an electronic glue setting oven. In a matter of seconds, the glue in the joint is cured.
Referring again to the schematic shown in FIGURE 9 of the drawing as this continuous board leaves the electronic oven, an automatic traveling cutoff saw severs the piece to the exact length required for a particular need. Such a board is produced with the grain running in a longitudinal direction. If the building unit of the present invention utilizes a construction wherein the shingle grain is parallel to the center supporting ridge, the piece produced in accordance with the above method would be acceptable. However, since the preferred embodiment of the present invention is constructed with the shingle grain direction parallel to the rafters it is necessary to further process the production piece now obtained.
Referring again to the schematic diagram of FIGURE 9 and also to FIGURE 13 to produce such a preferred shingle construction, the individual pieces 66 are edge glued to other pieces to produce a wide panel 62. In this case, the edges 63 are ripped to produce a smooth, square and straight edge for edge-glue application. The pieces 60 with adhesive on one edge are placed in a panel press 64 to form a panel forty-eight to fifty inches wide. The press sets the adhesive in about thirty-five seconds. In the present practice the wide panels are ripped to the desired width for each board. This is normally done by a gang rip saw with a number of adjustable blades. After the panels are ripped into individual boards these are trimmed to the length required. It is at this point that the applicant has devised a method to achieve the desired shingle grain direction. As the wide panels 62 leave the panel press 64 they are turned ninety degrees as depicted in FIGURE 14. They are then run through a gang rip saw 65 and cut across the grain in lengths approximating the length of the shingle desired much as depicted in FIGURE 14 of the drawing. The transverse edges of the pieces 67 thus produced are then run through the finger joint machine as described above which again cuts fingers in one transverse end and grooves in the other. As before when the pieces leave the joint machine a glue wheel applies adhesive to the grooves. The pieces are placed on a moving belt and carried into the roll press. In the former manner the finger joints are pushed together by the press rolls. As before the first pair of rolls runs faster than the next pair which forces the joints tight together forming a continuous board, which passes into the electronic glue setting oven. Again in a matter of seconds the glue in the joint is cured.
As this continuous board leaves the electronic oven, an automatic traveling cutoff saw severs the piece to exact length required for a particular need. The cut-to- .length pieces are carefully inspected and any defective joints are removed. It is the piece thus produced which forms the shingle portion of the building unit and which is then attached to the sheathing portion to form a complete unit. It should be noted as clearly depicted in FIGURES l, 2, 8, 11 and 12 that the grain of the shingle portion of the building unit runs parallel to the transverse edge of the unit.
This board may be used in the width as made and finished by a planer or sander, or it may be edge glued to other pieces to produce a wide panel. In this case, as before, edges are ripped to produce a smooth, square and straight edge for edge-glue application.
The process is the same as previously described with the pieces with the adhesive then placed in a panel press to form a wide panel. The normal press sets the adhesive in about thiry-five seconds.
The wide panels are now ripped to the desired width for each board. This is again accomplished by a gang rip saw with a number of adjustable blades. When the panels have been ripped into boards of the desired width they are then trimmed to the particular length desired.
Surface finishing of such boards can be done by a large drum sander. A plurality of sandpaper drums on the top and bottom surfaces sand to a satin smooth finish. If desired the edges are finished by an edge sizer machine. Lap joints or tongue and groove edges can be made by a tenoner machine. As the stock leaves the finishing machine a grader inspects each piece and removes any not up to grade and manufacturing standards. At the end of the operation to produce the simulated shingle effect the scoring lines at approximate shingle width are placed across the board in the direction of the transverse grain. In construction such as this the glue normally used is a melamine-urea adhesive which is waterproof, colorless and non-reactive with paints and other wood finishes. At this point in the operation the shingle portion with correct gnain direction and scoring means applied is laminated by suitable securing means to the sheathing portion. After the appropriate offset has been accomplished, the unit is then ready for installation across the rafters to produce a finished roof construction.
While the presently preferred form of the inventio has been illustrated and described herein, it will be appreciated that various changes may be made in the construction and arrangement of the parts without departing from the spirit of the invention, and it is intended that all such changes shall be embraced within the scope of the following claim.
A composite building unit for use as combined sheathing and weather facing to provide walls and roofs for building structures, comprising: a single, integral, elongate, natural wood sheathing board having a uniform Width and a uniform thickness, its length being much greater than its lateral dimensions, the grain of the board running lengthwise from end to end to provide the necessary strength to resist beam bending loads, said board being adapted to be secured in a horizontal position to studding or rafters in a building structure; and a plurality of weather facing members secured to said board; each of said members being rectangular in planform and formed of natural wood and secured to said board with its grain running at right angles to the grain of the board; said members being edgewise bonded to each other along their edges which extend transversely to the length of the board and being facewise bonded to the board to form a composite whole; the grain of said members extending vertically when the board is mounted in horizontal position to simulate conventional shingles and to shed water in the same way; said members combining to form a first lon- 'gitudinal edge substantially flush with a first longitudinal edge of said board and a second longitudinal edge parallel to the first and extending laterally well beyond the second longitudinal edge of said board to form an overhang portion; said members being Wedge-shaped with the thin portion of the wedge at the first longitudinal edge and 'With the overhang portion recessed on its underside to receive the first edge of an adjacent building unit; said unit being adapted to be combined with duplicate units to form a complete siding or roof for a building structure with the first edge of each board adjacent to the second edge of the succeeding board and with the first edge of the assembly of weather facing elements lying in the recess of the adjacent overhang portion; the building units being adapted to be firmly nailed to supporting structure with nails passing through substantially any part of the board and the overlying portion of the members, and with the overhang portion of the succeeding unit completely covering the nailing portion to hide the nails and protect them against corrosion.
References Cited by the Examiner UNITED STATES PATENTS 10,903 5/1854 Baker 52-539 1,078,776 11/1913 Dunton 523 13 1,171,081 2/1916 Aycock 52-3 14 1,702,609 2/1929 Lesher 52-519 2,009,812 7/1935 Olsen 52560 2,149,741 3/1939 Miles 52-394 2,241,642 5/1941 Mc'Cauley 52-539 2,256,435 9/ 19 41 Kraus 52-540 2,285,480 6/1942 Wilde 52540 2,384,686 9/ 1945 Kraus 52-540 2,569,831 10/ 1951 'Ryall. 2,659,938 11/1953 C r-oW-ther 52-539 EARL I. WIT MER, Primary Examiner.