Chimney Sleeve

In the United States, there are around 25,000 fires caused by chimneys every year. Approximately 20,000 of those 25000 chimney fires occur due to a lack of proper ventilation with prefabricated chimneys. Although much work has been done in the venting of chimney pipes themselves, the problem is that with the ubiquitous prefabricated chimneys, it is not just the chimney pipes that need ventilation but the chimney chases that they are placed in as well.

For example, a prefabricated chimney pipe is often placed inside what is called a chase. This chase typically extends above a building and surrounds the chimney pipe, providing protection to the elements and adding an aesthetic element that is more visually appealing than the cold metal of a prefabricated chimney pipe. While the chimney pipe will contain and direct the gasses from the fire up the chase and out the chimney, as the pipe heats up, it can heat up the inside of the chimney chase as well. If the chase is not ventilated, heated gas may build up and cause a fire—especially if the air from the chase is pulled down the chimney to replace rising air in the pipe.

This is a problem as old as prefabricated chimney chases. However, in the 1950s, when prefabricated chimneys were first created, no ventilation system was introduced. It was not until the 1980s, after testing by the original equipment manufacturer (OEM), that vented chimney chase pans were recommended. The OEM recommended vented chase pans that are lifted off the chase and overhang the edge of the chase itself, as shown in. Here, chimney pipeextends through the chaseand chase pan. The chase panis lifted off chase, which it also overhangs. This allows the heated gassesto be vented as the pressure and temperature in the chasebuild from the heated chimney pipe.

Although recommended by the OEM, the OEM had already shipped millions of prefabricated chimney chase pans, and did not see a reason to change the pans themselves, so, in the eyes of many in the industry, the OEM did not really proclaim the dangers of unvented chase pans-only making the recommendation to change the installation process to allow for venting by way of addendum to their fireplace instructions in 1985. No major changes were made in the chimney industry as a result. Thus, unvented chase pans remain common to this day. More than twenty million chimney chases in the United States at the time of this writing are not properly venting; with two to three million being added to that number every year.

The vented installation of chase pans has failed to catch on due to the lack of information on the dangers of unvented chases, confusion on the benefits of the overhanging chase pans (for example, thinking that it is to reduce damage caused by thermal expansion), the fact that many people do not like the look of an overhanging chase pan, and the fact that chase pans are harder to install in this way. This all adds up to mean that many chimneys are at risk, for example, in 2023, an improperly vented chimney chase caused a Fire Department Station in California to catch fire—even in some fire stations, properly installed chase pans are an afterthought.

The chimney faces another challenge as well. Chase pans often do not create a space between combustible and non-combustible materials. This creates problems for the chimney pipe as it heats up any combustibles touching it. These combustibles can catch fire, but many can also damage the chimney pipe just by heating up. Even without heat, these materials may wear down the chimney pipe over time if there is no clearance between those materials and the chimney pipe. This is also true for the chimney pipe and non-combustibles, for example, it is especially true in chimneys with a concrete chimney crown as often the concrete is poured right up to the chimney pipe. The concrete can be especially abrasive on the chimney pipe—causing it to corrode over time.

As a result, leaving a clearance between the chimney pipe and surrounding materials has been codified. However, even within the industry, it seems very few people are aware of these codes.

Therefore, there is a need to provide an elegant, effective, low-cost, quick-to-install method of venting chimney chase pans while protecting the chimney pipe from corrosion and presenting an aesthetically pleasing chase without an overhang.

The field of the present invention relates to the interaction of the chimney pipe or flue with materials as it exists a structure. Without limiting the indication thereof, the present invention provides mechanisms and methods for the venting of heated air from a chamber around a prefabricated chimney pipe while maintaining a clearance around the chimney pipe. The apparatus is low-cost, elegant, simple to install, and removes the need for overhanging chimney chase pans or caps while allowing previously built chimneys to be retrofitted to meet modern codes.

In at least one exemplary embodiment, the present invention comprises a sleeve having a first opening and a second opening opposite the first opening, both the first opening and the second opening capable of fitting around a vertical chimney pipe with a clearance. This sleeve is a barrier that allows mortar or other materials to be placed without touching the chimney pipe. The sleeve presents a clearance around the chimney pipe to allow the heated gasses around the chimney pipe to vent. In an exemplary embodiment, the sleeve may remain with the chimney pipe, but in at least one other, it may be removed.

In at least one exemplary embodiment of the present invention, the sleeve further comprises a support collar. This support collar enables the sleeve to sit vertically around the chimney pipe, and in an embodiment, this can occur without the sleeve being nailed or bolted to the materials around it. This collar allows for quick installation of the chimney sleeve as well. The support collar may be embedded in or supported by any materials placed around the support collar.

It is worth noting that the chimney sleeve with a clearance will have an opening facing the sky when placed vertically. This opening may allow for things to fall into the internal structure that the chimney exists from. If this clearance is covered, the ability to vent may be limited—without protection, though, there is a risk of rain, debris, or small animals among other things entering the structure. To help prevent this, a screen extension may be provided. Therefore, in at least one exemplary embodiment, the sleeve further comprises a vertical screen extension. This screen extension can be placed on the end of the sleeve so that when the sleeve is placed into position the screen helps protect the clearance around the chimney pipe.

It can be appreciated that this screen itself will not protect against rain or in at least one embodiment against falling debris without a cap or other cover. Therefore, in at least one exemplary embodiment that present invention comprises a sleeve, with a screen extension, and a rain collar. The rain collar can fit around the chimney pipe and rest on the screen extension. This collar will prevent rain and other small items from above from falling into the internal structure around the chimney pipe while the screen allows for heated gasses to vent under the rain collar.

Thus, a clearance and ventilation can be provided while still protecting the internal structure around the chimney pipe. It should be noted, however, that a sleeve itself can suit the purposes of the invention to provide a clearance and ventilation for chimney chase.

A chase pan may be made to provide a clearance around the chimney pipe by ensuring the hole of the chase pan is sufficiently large enough to provide the required clearance; a screen extension and even a rain collar may be placed onto this chase pan.

A chase pan can be fitted with the sleeve of the present invention or the support collar be modified such that it operates as a chase pan. The result is a chase pan, which has an opening that provides a clearance around the chimney pipe that clearance extends from the chase pan opening as a sleeve for the chimney pipe. This sleeve may then have the attachments described above of a screen extension, a rain collar, and/or a support collar when operably placed.

The sleeve may extend vertically in either direction from the chase pan, in some instances, only forming a chase pan collar. This chase pan collar may receive the attachments mentioned above.

It will be appreciated that these attachments do not fit inside the chimney pipe but rest outside it, like the sleeve. This allows for traditional chimney pipe venting, term caps, and the like to be used for the chimney pipe itself (as opposed to the chimney chase).

The present field of the invention is directed toward the improvement and safety of chimney termination points. The present invention provides mechanisms and methods related to the capping or crowning of a chimney. The mechanism and methods allow for the exchange of gasses between the chimney chase and the outlying environment, to allow gasses to vent. The present mechanisms and methods also allow for a clearance to be established around a chimney pipe or flue.

There is a need to vent gasses that are heated by a chimney pipe. Chimney pipes will heat the air around the pipe, and often, this air is contained. The heated air can build and cause fires to start. Exacerbating this problem is the presence of solid materials often touching the outside of the chimney pipe or flue at the termination point. The solid materials may react to temperature changes at a different rate than the chimney pipe and cause the pipe to tear or crack. These materials may also wear on the chimney pipe over time, causing abrasive damage, and depending on the material placed in proximity to the chimney, they may start a fire as well. So, it is a hope of this invention to help prevent fires by providing a clearance for chimney pipes and a system for venting around a chimney pipe.

It is worth noting that there are many styles and varieties of chimney [.] termination points. Commonly, residential chimneys will have chimney chases. The present invention may be applied to chases but also may be applied when the chimney terminates from other structures besides chases.

It will be appreciated that a clearance around a flue or pipe provides a venting mechanism for the chimney pipe or flue. This occurs because the clearance is on the outside of the pipe or flue, and thus it provides an opening for heated gasses to escape through. This clearance, by definition, results in keeping solid materials that may fatigue or damage the pipe or flue away from the pipe or flue.

With regard to the chimney sleeve of the present invention, in at least one exemplary embodiment, the sleeve fits around a chimney pipe to provide a clearance around the pipe, as shown in. The clearance may be any clearance that will begin to allow the gasses inside to vent to the outside. However, particular clearances can be selected. For example, clearances are 1 inch around the pipe for gas fireplaces and 2 inches around the pipe for wood-burning fireplaces. The result for a one-inch clearance around the pipe will often be a sleeve with a 10-inch diameter and for a sleeve with a two-inch clearance, a 12-inch diameter. As mentioned above, clearances may come in a range of sizes and may vary even around a single pipe or flue. Thus, it can also be said that an embodiment of the sleeve has at least a 1-inch clearance for a gas-burning fire and another at least a two-inch clearance for a wood fire.

These clearance dimensions hold true in the embodiment of the present invention, which is a chase pan that provides venting and clearance.

In at least one exemplary embodiment, the sleeve has a support collar. The support collar extends from the sleeve and may rest on or be embedded in the structure surrounding the pipe or flue. As the chimney termination point is often vertical, this support collar allows the sleeve to be supported by the structure around the chimney termination point.

Thus, in at least one exemplary embodiment, the present invention comprises a sleeve having a first opening and a second opening opposite the first opening, both the first opening and the second opening capable of fitting around a vertical chimney pipe with a clearance, and a vertical support collar operably attached to the sleeve and extending from the sleeve.

By fitting the sleeve around, not in the chimney, any clearance between the sleeve and the chimney will connect the chimney chase or internal structure environment with the external environment allowing the heated air to vent. By controlling the clearance between the sleeve and the chimney pipe, the amount of air vented can be controlled. By operating as a sleeve, this method of ventilation has the additional benefit of providing a clearance between the chimney pipe and other materials, including combustibles and non-combustibles, for example, concrete. This clearance is provided because the materials will be separated from the pipe by the sleeve.

Because the chimney pipe fits through the sleeve, the sleeve should have a first and second opening. As the chimney pipe may extend through the sleeve, chimney pipe components that fit the chimney pipe may still be used, for example, term caps and pipe vents, which are inserted into the end of the chimney pipe itself.

Because we are focused here on the chimney as it exits a structure, the chimney pipe will be vertical, and the sleeve must be able to fit the vertical chimney. To support the sleeve and to allow for potential modular attachments to the chimney sleeve a support collar is attached. This support collar allows the chimney to sit vertically by providing a collar that rests on it embedded in the surrounding material.

In at least one embodiment, the support collar for the sleeve is designed to be placed in a concrete chimney cap so that the sleeve may protect a clearance around the chimney pipe or flue and also serve as a vent. Typically, a concrete slab is supposed to be used in conjunction only with a masonry-type flue, but may also occur in practice, for example, when a previous masonry fireplace has been retrofitted with a prefabricated chimney pipe.

shows an exemplary sleeveof the present invention with a support collar. The sleeveis shown in a vertical configuration. The support collarextends perpendicular to the horizontal plane in this vertical configuration. This orthogonal orientation of the support collarallows the support collarto keep the sleevefrom falling into a chimney chase or other structure when the sleeve is vertically arranged to fit a vertical chimney pipe.

shows an exemplary sleeveof the present invention with support collarhaving folds. These foldsprovide support when the collar is embedded in a concrete cap. These folds help anchor the collar into the concrete.

To support the collar itself, during the construction of a chimney cap, the collarmay have wingletsor other connection points. For example, these winglets will help allow the sleeve to be placed into concrete when scaffolding is placed above the chimney termination point. The winglets may connect to such scaffolding to hold the chimney sleeve in place as the concrete is being set.

shows an exemplary sleeve with wingletsset in a chimney cap area. The wingletsattach to wooden boards placed above the chimney cap area. It can be seen that the support collarextends into the chimney cap areawhich will receive concrete. Notice that the opening of the sleeveprovides a space, with clearance, for a chimney pipe.

Although any level of clearance will provide protection for the chimney over no clearance and allow for some venting. To ensure the safe operation of a gas-burning chimney, the clearance should be at least an inch between the pipe and the sleeve, and for a wood-burning chimney, the clearance should be at least two inches between the sleeve and the chimney pipe. The differences between gas-burning and wood-burning chimneys are due to the different temperatures of the gasses that will flow through the chimney pipe. These minimum clearances are codified, and the sleeve provides an elegant solution for builders to ensure that these clearances are met while providing the additional benefits of venting.

In an exemplary embodiment of the present invention, a chase pan may be fitted with the sleeve of the present invention.shows a chase panwith a sleeveextruding from the chase pan. The center of the chase pan contains a hole that fits the sleeve. The sleeve may be a separate component, or it may be directly integrated into the chase pan. The sleeve may extrude from the top or the bottom of the chase pan, and in at least one embodiment, it extrudes from both the top and the bottom of the chase pan. The portion of the sleeve extruding from the top of the chase pan may serve as the chase pan collar.

In an exemplary embodiment of the present invention, the sleeve will extend from the top of the chase pan to form a chase pan collar. As a sleeve, this collar can be fitted with the sleeve extensions and attachments as discussed below.

One attachment, for example, is a screen extension. This screen extension can be placed on top of the sleeve as shown in. Here, sleevehas screen extensionplaced onto sleeve. It will be noticed that the screen extension shown here, and even the sleeve itself is not closed off but vertically open. This screen extensionhelps vent the gasses as the sleeve system grows more complex. It is also worth noting that the screen may be built into the sleeve itself and not necessarily placed on the top of the screen. In fact, in at least one embodiment, another sleeve may be placed on top of the screen extension.

The screen extensionmay be placed on the sleeveof chase pan. This forms a chase pan having an opening that fits the chimney pipe while providing a clearance; a sleeve serving as a chase pan collar; and a screen extension.

To close off the sleeve with a screen extension, a rain collar that fits the chimney pipe may be placed. In at least one embodiment, this rain collar may be of sheet metal which is not significantly abrasive to the chimney pipe. As shown in, the rain collarcan be placed on the screen extensionso that the rain collar fits around the chimney pipeand rests on the extension. For best practices when it comes to safety, the lower lip of the rain collarshould remain at least two inches above the bottom of the screen extension. Having a rain collar resting on the sleeve without a screen extension for the sleeve will prevent gasses from venting in most cases.

When the sleeve and accompanying system of the present invention are in place, the chimney pipe may still receive the usual attachments, such as a term cap. The term cap may be anchored inside the chimney pipe as usual because the system of the present invention does not utilize the inside of the chimney pipe. Further, the chimney pipe may still receive linings or insulation. In such cases, the sleeve may provide a clearance around the linings or insulation as well as the pipe itself.

As mentioned above, the sleeve of the present invention can be integrated with a chase pan. This sleeve may be connected to a chase pan. The sleeve would fit inside of the chase pan collar. This occurs but is not limited to occurring, by either having the support collar operate as a chase pan, placing the chase pan over the sleeve, or incorporating the sleeve as the chase pan collar.shows the supporting collarnow takes the shape of a chase pan while the sleeveacts as the chase pan collar. The sleeve does not drop down in the embodiment shown but may in others. In at least one exemplary embodiment, the sleeve has an additional support collar that can be embedded in a chimney cap.

Cases where a chase pan is placed over the sleeve, or other situations where the sleeve and chase pan are not integrated into each other, may occur. The sleeve itself does not preclude the use of chase pans. Further in such cases, and even when the screen collar is integrated with the chase pan, the screen extension may be moved to the chase pan. Such a case is shown in. Where screen extensionrest on the chase pan collar.

Even the rain collar and other attachments may be added to the chase pan.shows a chase pan. The chase panfits the sleeveinstead of the chimney pipe. The screen extensionis placed on the collar of the chase pan, and the rain collaris fitted around the chimney pipebut covers the screen extension as described in the discussion of. It is worth nothing that the sleeve and extensions may be placed before or after the chimney is placed as it fits over the chimney.

It will be appreciated that there are several ways to form the sleeve and support collar of the present invention. For example, the sleeve may be a sheet of metal rolled into a cylinder, which provides an even clearance around the chimney pipe; the sheet metal may be bolted or otherwise fixed to retain the sleeve's shape. The support collar may be cut out of sheet metal and combined with the sleeve, for example, by welding. This process of forming a sleeve with a support collar is shown in. Here, the metal sheetis rolled into a cylinderand bolted. Metal sheethas an areacut out, which will fit cylinder. This sheetmay be cut and folded to form folds(not shown). Sheetmay then be welded to cylinderto form the sleeve and supporting collar of the present invention. Once the cylinderis formed, a screen extensionmay be fixed to the cylinder, this may occur before or after the addition of the support collar. The attachments, indeed the apparatus itself, can be made at a factory or even at the job site.

Many innovative components of the invention have been discussed above in relation to the present invention and its embodiments. It is worth reviewing the individual components.

shows asleeve of the present invention. This sleeve is cylindrical but may be any shape that provides a clearance all around the chimney pipe (due to codes at the time of this writing, which require certain clearances, it will only be practical for now, to change the shape of the sleeve provided that the minimum clearances discussed above of one inch and two inches be maintained.) This sleeve should be long enough to provide clearance to the chimney pipe through the termination point. In many cases, 8 or 10 inches of length will be sufficient.

shows the support collarof the present invention. This support collar sits on the outside of the sleeve and supports the sleeve as it sits vertically aligned with the chimney pipe. There are many variations of the support collar possible, with the best variation for a task dependent on the details of the task. The support collar may have at least a two-inch ledge diameter in an exemplary embodiment. Further, as shown in, the supporting collar may have folds, which stabilize the support collar. The supporting collar may also utilize attachment aids, such as the winglets, shown in.

shows a chase panwith openingwith sleeve collarthat fits around a chimney pipe while providing a clearance. This chase pan allows hot air to vent without raising or overhanging the chimney chase.shows the chase pan ofnow with a screen extension. This screen extension improves the ventilation the chase pan offers when the clearance is covered.

shows two exemplary embodiments of the screen extension collar:andThe collar here is cylindrical, which fits a cylindrical sleeve or chase pan sleeve collar. However, the shape of the screen extension may vary. This screen extension may be placed on the chimney sleeve, for example. When it is placed, the screen extension will go around the chimney pipe. The screen extension extends at least one inch above the sleeve in an exemplary embodiment. As indicated by, many versions of the screen patterning may exist.