Патент USA US3095349код для вставки
June 25, 1963 w. G. CRAIG 3,095,339 ASPHALT ROOFING ELEMENT Filed March 25, 1958 INVENTOR. WILLIS G. CRAIG AT TORNEYS United States Patent ,0 3,095,339 1 1 Patented June 25, 1963 2 inches wide. This size is ideal for use in preparing new 3,095,339 roof surfaces and also is quite applicable in repairing worn ASPHALT ROOFING ELEMENT Willis G. Craig, Willoughby, Ohio, assignor to The Lubri zol Corporation, Wickliife, Ohio, a corporation of roo?ng surfaces. In some cases a worn roof surface, how ever, ‘may have sufficiently wide cracks in its surface as to require the use of a wider ?rst strip and in some severe cases a strip 12 inches in width will be most useful. The second strip, an asphalt-impermeable strip, nar rower than the ?rst, asphalt-bonded strip, must have a Ohio Filed Mar. 25, 1958, Ser. No. 723,903 4 Claims. (Cl. 154-51) This invention relates as indicated to a roo?ng element. tensile strength less than that of the asphalt-bonded strip. More particularly it‘relates to an asphaltic roofing ele The reason for this limitation upon the strength of the ment which is useful in prolonging the life of a built-up second strip is associated with its function in distributing roof surface. It is useful not only in the preparation of the stresses on the upper ?rst strip (occasioned by the new roof surfaces, but also in the repair of old, worn roof shifting of the supporting slabs of the roof surface) about surfaces. a wider area than that immediately over the joints between The roof surfaces of many buildings, particularly com these supporting slabs. mercial and industrial buildings, consist of ?at slabs of To illustrate the invention, an asphalt-impermeable strip concrete, metal, wood, etc. as the principal supporting about 2 inches in width is placed along the joint between structure. These supporting slabs are covered in most abutting concrete slaps of a roof surface and centered instances with asphalt-saturated felts to give the roo?ng thereon. Immediately above this 2-incl1 wide strip there a uniform protective coating. The asphalt-saturated felt 20 is placed a 4-inch wide strip of a porous alphalt-bonded serves not only to seal the joints between the abutting glass ?brous mat. This second, asphaltic mat is centered concrete slabs, but also to eliminate the crevices of these atop the lower, narrower strip so as to overlap on each joints and to provide a smooth surface which will prevent side of this narrower strip. Then the overlapping edges of the collection of water from rain and snow. the upper strip are anchored to the supporting concrete As the supporting slabs are not fastened either to each 25 slabs by mopping a clay asphalt emulsion on to the surface of this upper strip. The asphalt-emulsion impregn-ates the other or to their supporting understructure, but merely rest in their positions, it is ‘apparent that they will shift pores of this upper strip making contact with the concrete their positions from time to time with any shifting of the slabs underneath the overlapping edges and dries to leave building structure which they cover. It is apparent fur an effective seal between the concrete and the overlapping therrnore that such shifting of these supporting slabs will 30 portions of the asphalt~bonded glass mat. not be uniform, but that some will shift more than others. The second, ?exible, narrower strip, being asphalt Such motion of the slabs will place a considerable stress imperrneable, prevents attachment of the center portion upon that portion of the asphaltic layer immediately above of the upper strip corresponding to the area of the under the joints between any pair of slabs, This stress inevitably neath strip to the supporting roof structure. Because of results in the rupture of the asphaltic surface immediately 35 this and also because it is weaker in terms of tensile above these joints with the result that protection from strength than the upper ?rst strip it allows the stresses caused by any shifting of the abutting supporting slabs the elements ofweather is no longer provided by the as phaltic layer. I to be distributed throughout the upper asphaltic strip It is an object of the present invention to provide an im ‘about an area defined by the width of the lower, asphalt proved asphaltic roof surface. 40 impermeable strip. ‘Another object of the present invention is to provide a The invention may be illustrated further by reference to the ?gurwof the drawing. FIGURE 1 is a top View of the combination of strips placed over the joint of two abutting panels of a roof surface. The uppermost strip Other objects of the invention will become apparent 45 is de?ned by 5, 6, 7 and 8. The narrower, asphalt-im from the following description thereof. roo?ng element which serves as an effective seal of cracks in a roof surface. An effective means has been discovered whereby an as . permeable strip which lies immediately beneath the wider phaltic surface can be strengthened along the lines of joints between supporting slabs of the surface, Which con sists of a roo?ng element comprising in combination a strip and directly over the joint between the abutting panels is de?ned by the numbers 1, 2, 3‘ and 4. The abut with chopped nylon strands, cot-ton, jute, Orlon, etc. and asphalt-impermeable strip is tissue paper which has been ting panels are 9‘ and 10. FIGURE 2 is a cross-sectional ?rst strip of porous, asphalt-bonded ?brous mat 4 to 12 50 view of the same application in which the width of the inches wide, and centered longitudinally thereunder and . upper, asphaltic strip is represented by 13‘ and 14- and the width of the lower asphalt-impermeable strip is indicated in facewise contact therewith a second, asphalt-imperme by 11 and 12. The abutting panels are 15 and 16. able strip narrower than said ?rst strip and held in place by the surface tack of said ?rst strip, said second strip An important consideration in the selection of materials being characterized by a tensile strength less than that of 55 that can serve as the lower, narrower asphalt-impermeable said ?rst strip and an adhesion to asphalt less than the co strip- is that this material must be one which is free to move hesion of asphalt. either with respect to the supporting roof surface itself or The porous asphalt-bonded ?brous mat is preferably a with respect to the upper ‘asphaltic strip. It is apparent glass ?brous mat, and a particularly suitable asphalt that this condition must exist if the stresses caused by the bonded glass ?brous mat is described in U.S. 2,811,769. 60 movement of the supporting slabs are to be distributed Such a mat may be prepared by spraying hot discrete about an area wider that that of the joint being covered. asphalt particles upon a water-felted mat of chopped In some special circumstances this narrower, asphalt-im glass strands. A mat prepared in this manner is char permeable strip may be such that it adheres neither to the acterized by its great strength and light weight, and also supporting roof structure nor to the covering asphaltic by its relatively high concentration of asphalt with re 65 mat. Ordinarily, however, this narrower strip will be ad spect to its glass content. Other asphalt-bonded mats herent to one of these surface, and more usually this nar may also 'be used with success; thus an asphalt-bonded rower strip will adhere to the covering asphaltic strip. Saran ?ber mat is useful, so is an asphaltic mat prepared A particularly suitable material for use as this narrower many other synthetic ?bers can be used in the prepara 70 coated on one side with a thin ?lm of polyethylene. The tion of mats for the purposes of this invention. polyethylene ?lm serves to prevent adhesion of the strip Ordinarily this ?rst porous strip should be about 4 to the asphalt of old, worn roof surfaces, and also to pre 3,095,339 3 vent the combined strips from sticking to itself when it is rolled for storage purposes. Other materials which have been used with success as the asphalt-impermeable strip with respect to each other, must be capable of elongation. Likewise of course the anchoring substance (the residue include tissue paper alone (for use on new roof surfaces), Saran (a copolymer of 95% vinylidene chloride and 5% should also have this property. For the purposes of this invention it is necessary that this upper, asphaltic strip, vinyl chloride), aluminum foil, cellophane, and 20-pound when anchored to a roof surface, be characterized by an from the clay asphalt emulsion of the above illustration) elongation of at least 10% before rupture. Other modes of applying the principle of the invention may be employed, change being made as regards the de between abutting surfaces. These include polyvinyl alco 10 tails described, provided the features stated in any of the following claims or the equivalent of such be employed. hol, polyvinyl chloride, various vinyl chloride copolymers, I therefore particularly point out and distinctly claim polyvinyl acetate, GRS-type copolymers and the like. kraft paper. Still other materials which have been used successfully include synthetic resins which are painted over the joint The use of such materials as this narrower, underlying strip illustrates the situation in which this strip adheres to the supporting roof structure, but is free to move with re spect to the upper asphaltic strip. In this situation the asphalt-impermeable strip is suf?ciently ?exible to move with any movement of the abutting slabs of the roof. Being non-adherent with the asphaltic strip above, this movement does not transmit any stresses to the asphaltic strip. With respect to the situation in which the asphalt-im permeable strip adheres to the upper asphaltic strip, but does not adhere to the supporting roof structure, any movement of the abutting slabs of this roof does not transmit stresses to either of the strips which overlie the slabs because the narrower, asphalt-impermeable strip is independent of any such motion. As mentioned earlier the lower, asphalt-impermeable as my invention: 1. A roo?ng clement comprising in combination a ?rst strip of porous, tacky asphalt-bonded ?brous mat 4 to 12 inches wide, and centered longitudinally thereunder and held in facewise contact therewith by the surface tack of said ?rst strip, a second, asphalt-impermeable strip nar rower than said ?rst strip, said second strip being charac terized by ‘a tensile strength less than that of said ?rst strip and an adhesion to asphalt less than the cohesion of asphalt. 2. The roo?ng element of claim 1 characterized fur ther in that the ?rst strip of porous, asphalt-bonded ?brous mat is an asphalt-bonded glass ?brous mat. 3. The roo?ng element of claim 1 characterized fur ther in that the ?rst strip of porous, asphalt-bonded ?brous mat is an asphalt-bonded mat of chopped glass ?ber strands. 4. The roo?ng element of claim 1 characterized fur strip must have a tensile strength less than that of the 30 ther in that the second, asphalt-impermeable strip is a upper, asphaltic strip. If this is not the case the lower strip synthetic resin. will act to reinforce the upper strip and any stresses im posed upon the system will cause the upper strip to rupture along the lines which correspond to the edges of the lower References Cited in the ?le of this patent “reinforcing” strip. It is apparent therefore that the lower strip must have a suf?ciently low tensile strength that it does not act to reinforce the upper strip. The lower, asphaltic-impermeable strip should also be characterized by ‘an adhesion to asphalt less than the co hesion of asphalt. This property enables the lower strip 40 to become detached from the upper asphaltie strip or an asphaltic roof surface when stresses are applied to the system. A speci?c illustration of the invention is as fol lows: A 2-inch wide strip of polyethylene-coated tissue paper is placed (polyethylene side face down) atop the joint formed by abutting concrete slabs of a new roof. Immediately on top of this strip there is placed a 4-inch wide strip- of an asphalt-bonded, glass ?brous mat (prepared as in US. 2,811,769) such that a 1-inch selvage overlies each edge of the lower strip. An aqueous clay 50 asphalt emulsion containing 48% asphalt and 2% clay is UNITED STATES PATENTS 1,227,520‘ 1,637,480 1,642,282 A-ngier ______________ __ May 22, 1917 Gage ________________ __ Aug. 2, 1927 Weiss ______________ __ Sept. 13, 1927 1,694,523 1,751,327 2,078,049 2,133,183 2,314,523 2,315,851 2,550,465 White ______________ __ Dec. 11, Haire _______________ __ Mar. 18, Benedict _____________ __ Apr. 20, Baird ________________ __ Oct. 11, \Speer _______________ __ Mar. 23, Goldman _____________ __ Apr. 6, Gorski ______________ __ Apr. 24, 2,624,683 Bezman ______________ __ Jan. 6, 2,811,769 2,863,405 2,962,405 Craig ________________ __ Nov. 5, Lei'brook _____________ __ Dec. 9, Mortland ____________ __ Nov. 29, 1928 1930 1937 1938 1943 1943 1951 1953 1957 1958 1960 mopped on to the top layer until the pores thereof are OTHER REFERENCES thoroughly saturated. When the emulsion has dried the overall roof then may be surfaced by any of the methods well known in the art. It is apparent that the upper, asphaltic strip, being an chored to separate supporting slabs which are free to move Engineering News Record, Feb. 17, 1938, page 272. American Roofer, December 1946, pages 12, 13, and 25-27, inclusive. Addex publication RP. 75-28pa by Labco of Cleveland 6, Ohio, pages 1 and 2, Jan. 15, 1957.