US2993307A - Locking shingle - Google Patents

Description

F. J. WENDT LOCKING SHINGLE July 25, 1961 2 Sheets-Sheet 1 Filed June 28, 1956 INVENTOR.

July 25, 1961 F. J. WENDT 2,993,307

LOCKING SHINGLE Filed June 28, 1956 2 Sheets-Sheet 2 IN V EN TOR.

W M J4-w,%;, M4%4.

limited States Patent 2,993,307 4 LOOKING SHINGLE Frank J. Wendt, Chicago, 11L, assignor to United States Gypsum Company, Chicago, 111., a corporation of Illinois Filed June 28, 1956, Ser. No. 594,443 2 Claims. (CLEO-224) This invention relates to a locking shingle and more particularly to one with a novel type slot-tab interlock which affords improved resistance to tear and greater ease in insertion of the tab into an appropriate slot during attachment of the shingle to a roof.

A popular type of roofing material now being sold in large quantities for the covering of the sloping roof of houses is made by saturating a felt, usually formed from wood or rag fibers with asphalt, applying a coating of asphalt thereto and partially embedding colored granules into the coating. Sheets of roofing material formed in this manner are sold in roll, strip or individual form. This invention is concerned with those sold in strip form, particularly those known as thick-butt or square-butt asphalt shingles. These shingles are formed by cutting transverse slots or cut-outs part way in from the exposed or lower edge of the strip as far back as the shingle is to be exposed to form shingle simulating units which when applied to a roof give a pleasing shingled efiect. The exposed part is referred to as the butt" portion, that remaining and which is covered, the head portion. When these shingles are subjected to a wind of high velocity upon a pitched roof the exposed portion has a tendency to fold over and sometimes tear 011. This not only gives a very displeasing appearance but also may result in a roof leak.

A great number of means have been tried to overcome the tendency of the exposed or butt portion to blow oil under high wind velocity. Some of these are: cementing the butt portion down with a waterproof adhesive such as asphalt; stapling it to the course below; securing the bottom exposed edge to the course below by a clip extending around the bottom edge of each shingle unit; and locking the butt to the shingle below by means of a tab.

This invention relates to an improvement in the method of using tabs for locking the lower butt edge of the shingles in each course to the shingle immediately underneath. Many ways of effecting this locking have been set forth by the prior art and while such locking has improved the wind resistance of the exposed portions of the shingles, the tabs have been difficult to apply and they have been occasionally torn or disengaged due in part to the manner in which the shingles are raised by the wind when it blows from certain directions. Accordingly, it is an object of the invention to provide an improved locking tab by means of which the resistance to tear is increased coupled with an improvement in means for interlocking the parts of the shingles.

It is another object of this invention to provide a novel type of tab and slot combination for locking the butt portion of strip shingles to the shingles of the course underneath.

It is also an object of this invention to provide a means of locking down the butts of shingles which is easy to engage.

It is a further object of this invention to provide means of locking down shingles in which the locking tabs are stressed under high wind velocity in a novel manner tending to reduce the danger of tear.

It is a still further object of this invention to provide means for locking the exposed horizontal edge of strip shingles so that they will raise with the wind and orient 2,9d3,3d7 Patented July 25, 1961 danger of tear but still permit them to return to their original position after the wind has subsided.

It is' a further object of the invention to provide an improved roof construction utilizing shingles interlocked in a novel manner.

This invention may be further understood by reference to the drawings, in which FIGURE 1 is a view of a portion of a roof according to the invention showing the shingles in place and the tabs concealed;

FIG. 2 is a top view of a slot-tab shingle made according to the invention;

FIG. 3 is a view similar to FIG. 1, illustrating the position of a strip shingle as the tabs are about to be inserted into the slots, and

FIG. 4 shows the relative position of the tab and slot in a locked position when subjected to a high wind velocity.

Referring to the drawings, there is shown in FIG. 1 a roof construction 10 utilizing a series of shingle strips 11 according to the invention. Such shingle strips may be formed by cutting into the form shown in FIG. 2

from flexible asphalt roofing made by applying granules to an asphalt coating over asphalt saturated paper or rag felt. In the figures, the shingle strips 11 are shown as comprising a head portion 12 and a butt portion formed into two shingle-simulating units 13 and 14 by the cutout 15 extending inwardly and upwardly from the exposed edge. Two of these shingle-simulating units are usually in each shingle strip which is sometimes referred to as the square-butt type. The shingle simulating unit 13 is provided with a cut-out portion 27 of the same themselves thereto in a manner which will decrease .the

extent as cut-out 15 so that when the shingle strips are placed side by side, the appearance of individual shingles is achieved.

A slot 16 is cut into unit 13 inwardly from one edge of cut-out 15, and a slot 17 is cut into unit 14 as shown. The shingle unit 13 has a portion thereof extending beyond its lower horizontal or exposed edge, substantially medially situated, and referred to as the tab element 18.

Similarly, a tab 19 extends downwardly from shingle unit 14. The lower edges of the tabs may terminate in horizontal lines which are substantially parallel with the lower edge of the butts, or they may be inclined.

The tab 18 or locking segment upon the side facing away from slot 15 has a wide-mouthed or wedge-shaped recess 21 extending inwardly to form a throat 22 connecting the tab to the butt portion 13. The recess 21 is bounded above by the lower exposed edge 23 of the butt portion 13 and below by the upper edge of the tab which is inclined upwardly and inwardly to the throat. The lower edge of the recess is not continuous, for that near the outer edge of the tab extends upwardly towards but spaced fiom the exposed edge to form the lock or toe section 24. This section terminates abruptly in a hook edge 25 substantially right-angularly disposed (in the form shown) to the inclined lower edge of the recess. The toe section is an important part of the invention and is spaced a considerable distance from the throat portion so as to leave a large part of the lower or inclined boundmy of the recess 21 unaltered. The up per edge of the toe section may be inclined parallel to the lower edge referred to above or it may be at a different angle. In any case sufiicient space must be provided between the lower edge of the butt and the upper edge of the toe so as to facilitate the introduction of the tab into the slot 16 of an underlying shingle. The tab or locking segment 19 of butt portion 14 similarly is formed with a wedge-shaped slot 21a, a throat 22a, a toe or lock section 24a and a hook edge 25a.

The toes with their .hook edges have an important part in the retention of the tabs in the slots under severe wind conditions. In the drawings, the left tab 18 is shown wider than the right tab 19. This assists in inserting the tabs, for the left tab is inserted first into the slot 16 of an underlying'shingle'and may be partially engaged and still leave sulfiicient clearance for the insertion of the right tab into the slot 17 of the same underlying shingle. It is important, however, to have the hook edges at a sufiicient distance from the outside edge of the tabs so as to provide enough body to the toe sections to prevent tearing under stress, and hence it is un desirable to remove too much from the right tab.

The slot portions 16 and 17 referred to above, and into which are inserted tabs 18 and 19, respectively, of an overlying shingle, are formed by recesses cut inwardly along the upper exposed margins of the butt portions 13 and 14. The slots extend inwardly about the same distance as the width of the throat portions of the tabs. The lower boundaries of the slots may be substantially perpendicular to the edges of the butt portions. The upper boundaries are spaced a sufiicient distance from the lower to permit the ready insertion of the tab. It is preferred that the upper boundariesincline upwardly so as to form triangular- shaped slots 16 and 17 as shown in the drawing, as this has been found to greatly aid in inserting the tabs.

The shingle units are applied either individually or as a strip to the wooden roof deck in the same manner as for any other square-butt asphalt strip shingle. The nails are driven about one-half inch above the innermost point of the slots, as shown at 26 in FIG. 3, and at the free end in substantially the same line. The latter nail is not absolutely necessary but desirable- It; is important that the location of the nails with respect to the slots be close a above if maximum wind resistance is underlying shingle after it has been nailed down, as shown in FIG. 3. The butt portions of each shingle unit adjacent the slots 16 and 17 may be raised to aid in introducing the tabs. The shingle is adjusted until the tabs are completely inserted under the shingles of the underlying course in which position the throats thereof will coincide substantially with the lower portions of the slots and the lower exposed edges of the inserted shingle are substantially in line with the lower edges of the slots of the underlying shingle. This completely conceals the tabs as they are now under the underlying shingle with parts of the locking portions, including the toes, extending beyond the throats and the nails and firmly incased by the butt portions of the shingles of the immediately underlying course.

It will be found that the tabs are very easily inserted and moved in place in the direction shown by the arrows in FIG. 3. Considerable of this ease in insertion is due to the wide mouths of the wedge-shaped recesses 21 and 21a and to the wide mouths of the triangular-shaped slots 16 and 17 shown in FIG. 2. Theselatter slots may also be formed by widely spaced lines parallel with the extreme upper exposed margins of the butt portions. However, slots having an angular upper edge are greatly preferred, for they permit the tabs to slide and turn as they are drawn through the slots by the action, of the wind upon the butt portions and still the ,slots'provide means which will engage the hook edge of the tabs, thus stopping any further outward movement.

It has been found that the width of the slots 16 and 17 and 21 and 21a along the cut-out edge or mouth should be at least one-half inch. If the slots 16 and 17 were of this width along the full extent, the nails would be too far from the point at which the hook edges would be engaged. This, plus the extreme width of the slots throughout their entire length would not allow the hook edges to be caught in any manner and the tabs would release completely. On the other hand, whenthe upper 4 edges extend upwardly and outwardly at an angle the nail is close to the hook edges of the tabs as they assume their respective catch positions, and also the upper edges are in a position where they are more easily engaged.

It is not advisable, however, to have the upper edges of the recesses 21 and 21a intersect the lower edge of the shingle butt portions at an angle greater than 60 degrees; for otherwise there may not be enoughvmaterial between the nail and the slot to prevent tear-out. Arange of between thirty and forty degrees for the angle will be found quite satisfactory, with thirty degrees preferred. As mentioned-above, the lower range for the angle. is that which will give at least a one-half inch width to the slot at the cut-out.

In forming the angular slots 16 and 17 and 21 and 21a, it will be found from a practical standpoint that a clean acute angle of the upper and lower edge cannot be cutout so it is necessary to curve the intersection slightly such as with a radius of one-eighth inch.

When the exposed or butt portions are subjected to a wind of extremely high velocity the tabs will slide in the slots, thus permitting the butts to elevate to a limited degree and turn slightly to the right as shown in FIG. 4 so as to tend to place the throats of the tabs in tension rather than in twist. The tabs are much more resistant to failure by tension than by twist or tear. The tabs are stopped in their movement toward the right position of FIG. 4 by the hook edges 25 and 25a of the toes 24 and 24a, respectively, being firmly grasped by the shingles in the vicinity of the nails. The nails have firmly placed the shingles of the underlying course against those of the one next lower one. If the tabs did not permit the shingles to raise slightly by sliding through the slot to the desired position, the tab would be readily torn off by the wind; also, if the toes on the tabs are absent, the tabs would continue to slide to full release as there is nothing to catch or book onto the shingles of the next lower course. The tendency of the tabs to move when the butts are elevated by the wind until the shingle has reached the point where some of the tearing stress is relieved and then to be held firmly by the hook edge, greatly contributes to the success of the invention. When the wind subsides, the butt portions return to the original positions or maybe easily patted back into place with little damage.

While particular embodiments of the invention have been shown, it will be understood, of course, that theinventi on is not limited thereto since many modifications may be made, and it is, therefore, contemplated by the appended claims to cover any such modifications as fall within the true spirit and scope of the invention.

The invention having thus been described, what is claimed and desired to be secured by Letters Patent is:

1. An interlocking square butt type shingle comprising a head portion and a butt portion adapted to be exposed when a plurality of said shingles are laid in overlapping courses, said butt portion comprising at least one individual shingle-simulating unit and having a vertically extending cut-out disposed along one side thereof and extending inwardly from the exposed downward edge of said butt portion substantially its full length, a wedge-shaped, wide-mouthed slot extending inwardly from a side of said unit, said slot having a lower edge defined by a line extending along the extreme upper exposed margin of said butt portion and having an upper edge angularly disposed relative to and spaced from said lower edge, said lower and upper edges joined by a radial terminus at the inward end of said slot; a tab element extending beyond the exposed butt portion ofsuch unit, a wedge-shaped, wide-mouthed recess'extending into said tab from a side thereof opposite from said slot to form a throat between the remaining portion of said tab and said butt portion, said recess having an upper edge defined by the lower exposed edge of said butt portion and having alower edge inclined upwardly and inwardly at anangle' of between :thirty andforty degrees with said upper edge of said recess to form a radial terminus with said upper edge at said throat, an outer portion of said inclined edge extending beyond thereof but spaced from said exposed edge substantially more than the thickness of said butt portion to form a toe section, said toe section terminating in a hook edge, substantially right-angularly disposed to said inclined edge and adjacent to but spaced from said throat substantially more than the thickness of said butt portion; the width of said throat and the lower edge of said slot being of substantially the same dimension.

2. A roof construction comprising a series of courses of interlocking square butt type shingles, each of which shingles has a head portion and at least one butt portion adapted to be exposed when a plurality of said shingles are laid in overlapping course, said butt portion comprising at least one individual shingle-simulating unit having a vertically extending cut-out disposed along one side thereof and extending inwardly from the exposed downward edge of said butt portion substantially its full length, the butt portions of the shingles of one course overlying the head portions of the shingles of the immediately underneath course, each of said units including a wedgeshaped, wide-mouthed slot extending inwardly from a side of the respective unit, each of said slots having a lower edge defined by a line extending along the extreme upper exposed margin of said butt portion and having an upper edge angularly disposed relative to and spaced from said lower edge, said lower and upper edges joined by a radial terminus at the inward end of said slot; nails penetrating said shingles adjacent the inner ends of said slots; each of said butt portions including a tab element extending beyond the exposed butt portion thereof and each of said tabs including a wedge-shaped, wide-mouthed recess extending thereinto and directed oppositely to said slots to form a throat between the remaining portion of said tab and said butt portion, each of said recesses having an upper edge defined by the lower exposed edge of said butt portion and having a lower edge inclined upwardly and inwardly at an angle of between thirty and forty degrees with said upper edge of said recess to form a radial terminus with said upper edge at said throat, an outer portion of said inclined edge extending beyond thereof but spaced from said exposed edge substantially more than the thickness of said butt portion to form a toe section, each of said toe sections terminating in a hook edge, substantially right-angularly disposed to said inclined edge and adjacent to but spaced from said throat substantially more than the thickness of said butt portion, the shingles of each course being disposed so that each recess in each tab of each shingle is received in the cooperating slot of the immediately underlying shingle with each of said locking members disposed in a position to engage the adjacent nail upon raising of the shingle butt portions.

References Cited in the file of this patent UNITED STATES PATENTS 1,648,692 McCarthy Nov. 8, 1927 2,452,708 Abraham Nov. 2, 1948 2,598,497 Brown et al. May 27, 1952 2,659,322 Abraham Nov. 17, 1953 2,841,099 Abraham July 1, 1958 OTHER REFERENCES Roofing & Siding Contractor, May 1956, p. 4.

Images