Flashing For Roof Vent Pipes

Abstract

A flashing for roof vent pipes and the like in which a frusto-conical shield member surrounding the vent pipe has an enlarged flat base flange engaging the rooftop surface and an upper portion provided with a plurality of concentric cylindrical stepped portions selectively diametered to fit varying pipe sizes, the smaller stepped portion being readily severed from the remainder so that the next larger stepped portion will fit a larger pipe, with O-ring seals having slightly smaller inner diameters than the inner diameters of the vent pipe engaging stepped portions being fitted adjacent thereto for sealing engagement with the vent pipe. At least a portion of the shield member has circular corrugations extending therearound so that the shield will flex to conform with slight differences in roof pitches, as well as to provide flexing required by expansion and contraction of the building structure.

Description

REFERENCE TO RELATED PATENT

The present application constitutes an improvement over my issued U. S. Pat. No. 3,602,530 dated Aug. 31, 1971.

BACKGROUND OF THE INVENTION

The present invention relates to devices for retaining and sealing roof vent pipes and the like of different diameters where they extend through the roof to prevent water leakage at their juncture with the roof.

DESCRIPTION OF THE PRIOR ART

The following patents are known: U. S. Re 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, as well as my own U. S. Pat. No. 3,602,530.

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 their inability to withstand weather and to conform to expansions and contractions of the vent pipe and other roof structure over protracted periods. Other ordinary constructions utilize metal flashings at the juncture of the vent pipe and the roof, with sealing being provided by soldering 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 vent pipes of particular diameters and since vent pipes usually come in different diameters building contractors must maintain a supply of all sizes of flashings.

SUMMARY OF THE INVENTION

My invention described and shown in U. S. Pat. No. 3,602,530 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 substantially concentric cylindrical stepped portions, such that the inner or smaller diameter stepped portion may be readily severed from the flashing to expose another larger stepped portion readily fitting the particular pipe and to form a seal around the periphery of the vent pipe even when the same has minor imperfections. The flashing also has the capability of conforming readily to varying roof pitches and is readily adaptable to expansion and contraction of the roof structure.

The embodiment of the present invention constitutes an improvement in which separate O-ring seals are carried adjacent the stepped portions internally adjacent thereof for close fitting to the vent pipe when the flashing is installed, providing a yet more effective and permanent seal between the flashing and the vent pipe.

DESCRIPTION OF THE DRAWINGS

A more complete understanding of my invention may be had by reference to the accompanying drawings illustrating several 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 of a preferred embodiment of the present invention installed around a vent pipe;

FIG. 2 is a top view of the vent pipe and flashing of FIG. 1;

FIG. 3 is a vertical cross-sectional view taken through the rooftop flashing of FIG. 2 and indicating in phantom lines vent pipes of different diameters extending therethrough;

FIG. 4 is an enlarged fragmentary cross-sectional view of a portion of the flashing illustrating more in detail the location of the cutting line to remove the top flange or rim of the flashing for enlargement of the diameter of the opening; and

FIG. 5 is another perspective view of the flashing of the present invention illustrating the top or inner flange or rim of the flashing being removed to accommodate a vent pipe of larger diameter.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As illustrated in FIG. 1, a rooftop 10 has a conventional vent pipe 12 extending vertically therethrough and may also have a conventional vent pipe cap, which is here omitted for clarity.

The improved structure comprises a flashing 14G which peripherally engages the vent pipe 12, and has a flat base 16G adapted to be secured to the rooftop 10, as shown, by any means such as nails or the like. The flashing 14G comprises a substantially frusto-conically shaped body 18G extending from the flat base 16G at an oblique angle relative to the plane of the flat base 16G. The upper rim is formed, as shown, into a pair of concentric cylindrical stepped portions 96 and 98 connected to each other and to the body of the flashing by connecting ridge portions 96a and 98a respectively. The uppermost portion 96 is dimensioned so that its inner surface will conform substantially with the outer diameter surface of a vent pipe 12, in this case being a conventional three inch O.D. pipe, indicated in phantom lines. In the event the flashing 14G is to be used with a larger pipe, as for example a conventional four inch O.D. pipe indicated by the phantom line 12A in FIG. 3, the uppermost portion 96 is removed by cutting or otherwise severing the top 97 of the flashing at the junction formed by the ridge 96a with the inner cylindrical portion 98 along a cutting line 100, as shown in detail in FIG. 4.

As particularly seen in FIG. 3 and in larger detail in FIG. 4, each of the portions 96, 98, which are concentric with each other around a center line "X" of the flashing, is provided with an O-ring or other similar sealing means 102 and 103 respectively which are of slightly smaller inner diameter than the respective vent pipes 12 and 12A and are compressible to a degree such that the O-ring seals will each conform readily to the shape of the respective vent pipe including its minor imperfections and irregularities to maintain a satisfactory water seal between the vent pipe and the flashing inner surface. If necessary the O-ring seals 102 and 103 may be bonded to the inside of the portions 96, 98 to securely keep them in place, or could be otherwise formed integrally with the material of the flashing.

A plurality of circular corrugations 104 extend around the annular portion (respective to the roof line) of the body 18G of the flashing 14G so that it will flex within limits to conform the base 16G to rooftops of varying pitches, and also to adapt to contractions and expansions of the roof structure.

With particular reference to FIGS. 4 and 5, if it is desired to use a vent pipe 12A of larger diameter, the top portion 97 of the body 18G of the flashing is cut off along the line 100 (FIG. 4) just below the uppermost portion 96. The cutting line 100 is on a plane normal to the central axis "X" (FIG. 3) of the flashing and thus assures concentric installation of the larger vent pipe 12 in the flashing around the central axis "X." It will be seen in FIG. 4 that, after the top portion 97 has been cut off along line 100, an axial cylindrical ridge portion 99 remains as a continuity of the inner portion 98 and forming together therewith a retaining means for the O-ring 103, holding the O-ring in place as it is compressed on the flashing being installed downwardly over the vent pipe. The flashing is formed to have a somewhat thinner periphery along the plane of the line 100 for easier cutting.

As seen in FIG. 1, the flashing 14G is installed on the rooftop 10 in such a fashion that a portion of the flat base 16G is extended underneath the shingles 11 and the remaining portion lies on top of the shingles 11. However, the particular securement of the flashing to the rooftop 10 is immaterial and forms no part of the present invention.

The flashing 14G may be a stamping made from sheet metal, but is preferably molded of a suitable plastic or any other suitable and easily formable sheet material.

The construction herein described thereby provides a vent pipe flashing structure having an expanded versatility. If the flashing is made of plastic, polypropelene or polyethylene may be used, which have the properties required to conform sufficiently to the imperfections in the pipe and retain the shape of the pipe's imperfections and irregularities at all times thereafter, while yet being weather resistant, tough and durable, as well as being slightly flexible for the purpose 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, particularly in conjunction with the use of the O-ring seals as shown, 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 one preferred embodiment 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 or the scope of the appended claims.

Claims

I claim:

1. A flashing for rooftop vent pipes and the like of different diameters, comprising:

a substantially frusto-conical shield member for enclosing a portion of said vent pipes upstanding from said rooftop and having a base adapted to engage the rooftop surface, said shield member having a plurality of stepped upper portions of varying diameters dimensioned to engage the outer diameters of differently sized vent pipes, at least said upper portions being of a material having the properties of deforming slightly to conform to the shape of said pipes including minor imperfections thereof, the smaller of said portions being severable for adapting said shield to selected vent pipes, and

sealing rings fitting within portions of said shield immediately below and of larger diameters than said stepped upper portions, said sealing rings having slightly smaller inner diameters than the adjacent upper portions for effectively sealing said pipes relative to said shield member.

2. The flashing as defined in claim 1 in which said sealing rings are readily deformable to conform to manufacturing variations in the diameters of said pipes.

3. The flashing as defined in claim 1 in which a portion of said shield intermediate the flat base and the upper portions has corrugations extending in planes at an angle oblique to the central axis of said vent pipes, and said shield member being distortable in the area of said corrugations without distortion in the area of said stepped upper portions and to a degree whereby the flat base may move relative to the axis of said pipe to conform selectively to different roof pitches and to adapt to normal roof structure contractions and expansions.

4. The flashing as defined in claim 1 in which said shield member has its smaller end constituting the upper portion and the larger end being integral with the flat base.

5. The flashing as defined in claim 1 in which said upper stepped portions are adapted to retain said sealing rings which are outwardly expansible upon engaging around said pipe.

6. The flashing as defined in claim 1 and having annular ridge portions intermediate said stepped upper portions for indicating a separation line and facilitating easy separability of said smaller upper portion.

7. The flashing as defined in claim 1 in which a portion of said shield intermediate said base and said upper stepped portions has small step-like corrugations extending in planes substantially parallel to the plane of said base, and said shield member being slightly distortable at least in the area of said corrugations to a degree whereby said base may move relative to the central axis of said pipe to conform selectively to different roof pitches and to adapt to roof structure contractions and expansions.