A chimney breast is a portion of a

chimney A chimney is an architectural ventilation structure made of masonry, clay or metal that isolates hot toxic exhaust gases or smoke produced by a boiler, stove, furnace, incinerator, or fireplace from human living areas. Chimneys are typic ...

which projects forward from a wall to accommodate a

fireplace A fireplace or hearth is a structure made of brick, stone or metal designed to contain a fire. Fireplaces are used for the relaxing ambiance they create and for heating a room. Modern fireplaces vary in heat efficiency, depending on the design. ...

. Typically on the ground floor of a structure, the

masonry Masonry is the building of structures from individual units, which are often laid in and bound together by mortar; the term ''masonry'' can also refer to the units themselves. The common materials of masonry construction are bricks, building ...

extends upwards, containing a

flue A flue is a duct, pipe, or opening in a chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors. Historically the term flue meant the chimney itself. In the United States, they are al ...

which carries

smoke Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product ...

out of the building through a

chimney stack A chimney is an architectural ventilation structure made of masonry, clay or metal that isolates hot toxic exhaust gases or smoke produced by a boiler, stove, furnace, incinerator, or fireplace from human living areas. Chimneys are typ ...

. Chimney

jamb A jamb (from French ''jambe'', "leg"), in architecture, is the side-post or lining of a doorway or other aperture. The jambs of a window outside the frame are called “reveals.” Small shafts to doors and windows with caps and bases are know ...

s similarly project from the wall, but they do so on either side of the fireplace and serve to support the chimney breast. The interior of a chimney breast is commonly filled with

brickwork Brickwork is masonry produced by a bricklayer, using bricks and mortar. Typically, rows of bricks called '' courses'' are laid on top of one another to build up a structure such as a brick wall. Bricks may be differentiated from blocks by s ...

concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wi ...

. The construction and appearance of a chimney breast can vary according to function and style. English and American builders more often treat the chimney breast and fireplace as distinct architectural features, whereas French buildings have gradually trended towards concealed construction.

False chimney breasts

False chimney breasts are sometimes constructed around a twin-walled flue or against a wall pierced by a flue for purely cosmetic purposes. Typically they will consist of a timber frame or stud work covered with plaster board and a plaster skim. If the false breast contains a flue, it may be necessary to line it with a

refractory In materials science, a refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Refractories are polycrystalline, polyphase, ...

material such as

vermiculite Vermiculite is a hydrous phyllosilicate mineral which undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently, and commercial furnaces can routinely produce this effect. Vermiculite forms by the wea ...

. Usually, additional cosmetic features will be added, such as cosmetic beams,

overmantel The fireplace mantel or mantelpiece, also known as a chimneypiece, originated in medieval times as a hood that projected over a fire grate to catch the smoke. The term has evolved to include the decorative framework around the fireplace, and ca ...

s or fireplace surrounds.

Removal

Chimney breasts often become redundant with respect to their function as a chimney after the installation of alternative heating methods, such as

central heating A central heating system provides warmth to a number of spaces within a building from one main source of heat. It is a component of heating, ventilation, and air conditioning (short: HVAC) systems, which can both cool and warm interior spaces. ...

. Removal of the chimney breast can provide more floor space and a more regular shaped room. However, chimney breasts often have structural function. Therefore, removal needs to be done with care, and preferably with professional advice. The removal of part (especially the lower part) of a breast can cause uneven loading on a wall, especially if the upper part is not suitably supported, ideally on an

I-beam An I-beam, also known as H-beam (for universal column, UC), w-beam (for "wide flange"), universal beam (UB), rolled steel joist (RSJ), or double-T (especially in Polish language, Polish, Bulgarian language, Bulgarian, Spanish language, Spanish ...

. In some cases, support on a steel beam and post, or by

gallows bracket A gallows (or scaffold) is a frame or elevated beam, typically wooden, from which objects can be suspended (i.e., hung) or "weighed". Gallows were thus widely used to suspend public weighing scales for large and heavy objects such as sacks ...

s may be acceptable. Other factors that need to be considered when removing a chimney breast are: * Fire safety, in particular for party walls. * Noise insulation * Effect on neighbour's chimney * Damp prevention * Ventilation

References

{{Reflist

External links

How to wallpaper a chimney breast
Chimneys Architectural elements