Flashing For Roof Vent Pipes

Abstract

A flashing for roof vent pipes and the like in which a shield member surrounds the vent pipe and has a base flange engaging the rooftop surface and an upper edge provided with a plurality of concentric inner rims selectively diametered to fit varying pipe sizes, the inner rim being readily severed so that the outer rim will fit the larger pipe, the flashing being made of a material which will deform to a degree, to conform with the shape of the pipe including minor imperfections thereof and to retain such conforming shape thereafter. The rims in some embodiments have small corrugations to permit sufficient pipe shape conforming deformation, and at least a portion of the shield member has semicircular or circular corrugations extending substantially normal to the axis of the vent pipe or substantially parallel with the base flange so that the shield will flex to conform with slightly different roof pitches as well as to provide flexing required by expansion and contraction of building structure.

Parent Case Text

This application is a continuation-in-part of Pat. Application Ser. No. 733,154, filed May, 1968, now abandoned.

Description

BACKGROUND OF THE INVENTION

1. Field of The Invention

The present invention relates to devices for sealing roof vent pipes and the like where they extend through the roof, to prevent water leakage therethrough.

2. Description of the Prior Art.

The following patents are known to me: U.S. Reissue No. 26,026, and U.S. Pat. Nos. 558,025; 580,515; 1,000,506; 1,258,884; 1,317,446; 1,558,503; 2,244,280; 2,985,465; 3,098,663; 3,151,894; 3,163,101, and Belgium Pat. No. 511,895. Flashings previously used have sometimes been made of rubber and the like materials which are intended to stretch around the vent pipe for sealing thereof, but they are usually not satisfactory due to inability to weather and conform to expansions and contractions of the vent pipe and other roof structure over protracted periods. Other ordinary construction utilizes metal flashings at the juncture of the vent pipe and the roof with sealing being provided by leading or caulking around the joint of the flashing with the vent pipe, but these, too often, crack and leak water, and rust out with time. Flashings customarily are made in sizes to fit particular vent pipes, and since vent pipes usually come in different sizes, building contractors must maintain a supply of all sizes of flashings.

SUMMARY OF THE INVENTION

My invention has for its primary object the formation of a vent pipe flashing which is readily adaptable to various pipe sizes, the flashing having a plurality of and preferably two, substantially concentric rims, such that the innermost rim may be readily severed from the flashing to expose the outermost rim, and with the rims so constructed to form a satisfactory seal around the periphery of the vent pipe even when same has minor imperfections. The present flashing also has the capability of conforming readily to varying roof pitches and adapting to expansion and contraction of roof structures, and may be made large enough to enclose pipes and their existing flashings if necessary.

DESCRIPTION OF THE DRAWING

A more complete understanding of my invention may be had by reference to the accompanying drawings illustrating preferred embodiments of the present invention in which like reference characters refer to like parts throughout the several views and in which:

FIG. 1 is a fragmentary perspective view of a rooftop showing a flashing embodying the present invention installed around a vent pipe;

FIG. 2 is a fragmentary vertical cross-sectional view taken through said rooftop, the vent pipe extending therethrough, and the flashing embodying the present invention;

FIG. 3 is a top view of the vent pipe and flashing of FIG. 2;

FIG. 4 is a cross-sectional view taken substantially on the line 4--4 of FIG. 2;

FIG. 5 is a fragmentary cross-sectional view of a portion of a flashing illustrating another embodiment of my invention;

FIG. 6 is another fragmentary cross-sectional view of a portion of a flashing illustrating another embodiment of the invention;

FIG. 7 is a cross-sectional view substantially similar to that of FIG. 2, but illustrating the use of the present flashing with a vent pipe having a preexisting flashing;

FIG. 8 is a fragmentary cross-sectional view of a portion of a flashing illustrating yet another embodiment of the invention;

FIG. 9 is a fragmentary cross-sectional view of the flashing of FIG. 8 as installed on a vent pipe but with the inner channel portion having been severed;

FIG. 10 is a fragmentary cross-sectional view of a portion of a flashing illustrating a further embodiment of the invention;

FIG. 11 is a fragmentary cross-sectional view of the flashing of FIG. 10 as installed on a vent pipe but with the inner channel portion having been severed;

FIG. 12 is a plan view of another preferred flashing embodying the invention;

FIG. 13 is a cross-sectional view taken substantially on the line 13--13 of FIG. 12;

FIG. 14 is a cross-sectional view of another embodiment of the flashing similar to FIG. 13 but with different corrugations; and

FIG. 15 is a fragmentary cross-sectional view of another modification of the flashing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As illustrated in FIG. 1, a rooftop 10 has a conventional vent pipe 12 extending vertically therethrough, with the conventional vent pipe cap omitted for clarity.

The present invention comprises a flashing structure 14 in the form of a shield which peripherally engages the vent pipe 12 and has a base flange 16 which overlies the rooftop 10 as shown.

In the embodiment of the invention illustrated in FIGS. 2, 3 and 4, the flashing shield is seen to comprise a substantially frustoconically shaped body 18 extending from the base edge 16 to an upper rim formed as shown into a pair of concentric inverted U-shaped channel portions 20 and 22 providing vertically extending annular flanges 20A and 22A respectively. The channel portions 20 and 22 are connected by means of a horizontal ring portion 24. The innermost flange 22A is dimensioned so that its inner surface will conform substantially with the outer diameter surface of the vent pipe 12, in this case being a conventional 3 inch o.d. pipe. In the event the flashing 14 is to be used with a larger pipe, as for example a conventional 4 o.d. pipe, indicated by the phantom line 12A of FIG. 2, the inner diameter channel portion 22 is removed by cutting or otherwise severing the flashing around the junction of the ring portion 24 with the outer channel portion 20 along the concentric line 26 shown in FIGS. 3 and 4. When installed on the larger pipe, the inner surface of the outermost flange 20A is dimensioned to conform substantially with the outer diameter surface of the vent pipe 12A.

The material of the flashing 14 is a plastic having the property of being to a degree distortable, such that the aforesaid flange surfaces will each conform readily to the shape of the respective vent pipe including its minor imperfections and irregularities, and such that said flange surface will retain this shape at all times to maintain a satisfactory water seal around the pipe.

As an aid in providing the ready conformation of the inner surfaces of the vertical flanges 20A and 22A to imperfections in the vent pipe 12 or 12A, there may be provided closely spaced, small vertical corrugations 28 on the outer surfaces of the flanges 20A and 22A. If the diameter of the flanges 20A and 22A are made to be no larger than the smallest of the vent pipe diameters within their tolerances, the corrugations 28 will readily permit the slight distortions necessary to achieve a good seal of the flange inner surfaces around the vent pipes.

A plurality of semicircular corrugations 30 extend around the upper annular portion (respective to the roofline) of the body 18 of the flashing 14 so that it will flex within limits to conform the base edge 16 to rooftops of varying pitches, as indicated by phantom lines 10A and 10B of FIG. 2, and also to adapt to contractions and expansions of roof structure.

FIG. 5 illustrates a modified construction in which the channel portions 20 and 22 are provided respectively with flanges 20B and 22B which have inner pipe engaging surfaces convexly contoured as indicated, such convex surfaces being adaptable to readily conform to imperfections and slight size variations of the vent pipes against which they are engaged.

FIG. 6 illustrates another modification in which the channel portions 20 and 22 have flanges 20C and 22C respectively formed on radii as shown to provide similar types of convex pipe engaging surfaces.

At times, it may be necessary to use a vent pipe flashing with a construction which has a preexisting flashing and being required where the old flashing may have rusted out or become cracked or damaged by age and inclement weather. In practice heretofore, the old flashing is first removed, and a new flashing installed, but in the present flashing, shown in FIG. 7 as a flashing 14A, flanges 20D an 22D are at a higher level than the preexisting flashing 32.

FIGS. 8 and 9 illustrate another modification of my invention. In FIG. 8, a flashing 14C has outer and inner inverted arcuately U-shaped channel portions 60 and 62 providing respectively flanges 60A and 62A which are indicated to be of smaller diameters than the outer diameters of the vent pipes with which they are adapted to be installed, respectively indicated by phantom lines 64 and 64A. When this flashing is installed, the channel portion (60 or 62) will bulge outwardly to a degree, FIG. 9 illustrating the outer channel portion 60 encircling the large diameter pipe 64, in a manner to force the inner surface of the flange 60A snugly against the pipe 64 so that it will conform to the shape of the pipe including its minor imperfections.

FIGS. 10 and 11 illustrate yet a further modification, in which a flashing 14D has inverted V-shaped channels 70 and 72 with inner sloped flanges 70A and 72A adapted to engage respectively with vent pipes indicated by phantom lines 74 and 76. The inner channel 72 may be removed by severing along the line 78 which is the junction of the flange 70A of the outer channel 70 with the inner channel 72, there being no connecting ring as in previously described modifications.

FIG. 11 shows installation with the larger o.d. vent pipe 74, in which the outer channel flange 70A rolls up, as the flashing 14D is pushed downward over the pipe 74, turning inside out so that its normal outer surface engages the outer surface of the pipe 74, the channel shape effecting the necessary sealing pressure so the pipe-engaging surface of the flange 70A will conform to pipe irregularities and imperfections. The inner surfaces of the flanges 70A and 72A may be corrugated as shown in FIG. 10 to further facilitate the necessary deformation and conformation to the pipes when installed.

FIGS. 12 and 13 illustrate another modification of the invention in which a flashing 14E is provided with a large square base flange 16E having holes 17 for securing to a roof under the shingles thereof (not shown). The flashing has a substantially frustoconically shaped body 18E provided with substantially semicircular steps or corrugations 74 extending in planes substantially parallel with the plane of the base flange 17. The upper edge of the frustoconical portion 18E has an inwardly formed annular shoulder 76 with a further frustoconical upper portion 78 integral with the inner edge of the annular portion 76 . The upper portion 78 is dimensioned and adapted to fit substantially close about a minimum diameter vent pipe (not shown). Since vent pipes are not made with very close tolerance, occasionally it may be necessary to trim off a small upper section of the portion 78, and for this purpose an annular groove 80 is provided so that it can readily be cut off at this point.

For use on a larger size vent pipe, the entire annular shoulder 76 and upper portion 78 may be removed by cutting around an annular groove 82 provided at the juncture of the frustoconical portion 18E and the flange 76. Again, since the pipes are not made with close tolerance, it may be necessary to trim off a small additional portion, and for this purpose a further annular groove 84 is provided as shown.

FIG. 14 illustrates a flashing constructed substantially similar to the flashing of FIGS. 12 and 13, except that completely peripheral steps or corrugations 74A are provided around the frustoconical portion 18E in planes aligned substantially parallel to the plane of the base flange 17 as shown. This modification permits the flashing to flex to a greater degree and is more readily adaptable to larger variations in roof slope and to larger degrees of expansion and contraction of roofing structure. Otherwise, the flashing of FIG. 14 is the same as the flashing of FIG. 13 and is used in the same fashion.

FIG. 15 illustrates a modification of the flashing of FIG. 14 in which the frustoconical portion 18F has an outer rim portion 90 and an inner rim portion 91, each having a slight uniform conicity relative to the vent pipe axis A. The portions 90 and 91 are connected by a flange 93, and at the juncture of the flange 93 and rim portion 90 a shallow step 94 is provided as a guide for a cutting knife to permit the severing of the inner rim portion 91 and flange 93. The slight conicity of the rim portions 90 and 91 enables them to be installed snugly around the appropriately sized vent pipes and conform not only to slight irregularities but also to different tolerance dimensions. The rim portions 90 and 91 also have sufficient vertical length to provide an adequate sealing surface around the vent pipe.

The various constructions above described thereby provide a vent pipe flashing structure having an expanded versatility. The plastic which is preferably used for the flashing is polypropelene or polyethylene which have the properties required to conform sufficiently to the imperfections in the pipe and retain the shape of the pipe's imperfection and irregularities at all times thereafter, while yet being weather resistant, tough and durable as well as being slightly flexible for the purposes described. Multiple size usage of the single flashing structure reduces the contractor's inventory of flashings, and the flexible and slightly deformable properties of the plastic eliminates the necessity for caulking and prevents thermal expansion and contraction of the vent pipe from cracking the flashing or breaking the seal.

Although I have described only a few preferred embodiments of my invention, it will be apparent to those skilled in the art to which the invention pertains that various changes and modifications may be made therein without departing from the spirit of the invention as expressed in the scope of the appended claims.

Claims

I claim:

1. A flashing for rooftop vent pipes and the like comprising

a. a shield member enclosing a portion of said vent pipe upstanding from said rooftop,

b. said shield member having a base flange adapted to engage the rooftop surface,

c. said shield member having a first substantially frustoconical portion integral with and upstanding from said base flange and having an upper annular edge dimensioned to engage the outer surface of a vent pipe of one predetermined diameter, an inwardly formed shoulder integral with the upper edge and having an inner annular rim, and a second substantially frustoconical portion integral with and upstanding from said inner annular rim and dimensioned to engage with the outer surface of a vent pipe having a second predetermined diameter,

d. said rim and the second portion integral therewith being adapted to be severed from said first frustoconical portion for use with the vent pipe having the first predetermined diameter,

e. said shield being of a material having the properties of deforming slightly, of conforming to the shape of said vent pipe including minor imperfections thereof, and of retaining such conforming shape thereafter, and

f. a portion of said first frustoconical portion having small steplike corrugations extending in parallel planes around said frustoconical portion, and said shield member being slightly distortable at least in the area of said corrugations to a degree whereby the base flange may more relative to the axis of said pipe to conform selectively to different roof pitches and to adapt to roof structure contractions and expansions.

2. The flashing as defined in claim 1 and in which said corrugations extend substantially semicircularly around said shield.

3. The flashing as defined in claim 1 and in which said corrugations extend in planes substantially normal to the axis of said vent pipe.

4. The flashing as defined in claim 1 and in which said corrugations extend in planes substantially parallel to said base flange.