What do all the technical terms actually mean?
 A.C.E.
The Association of Chimney Engineers
B.B.A.
The British Board of Agrement. A government funded body responsible for testing and approving products and systems used in the Building and Construction Industry. Certified products and systems can carry the BBA logo
Boiler
Closed burning appliance designed to transfer heat from combustion to water or air which in turn is used for heating remote parts of dwelling - can burn any fuel.
Bressemer
The bressemer is the large timber or stone that form the top of an inglenook fireplace.
Carbon Monoxide
Carbon Monoxide is almost always found in the exhaust gases of burning appliances. It is the result of restricted combustion. The gas is highly toxic and inhibits the blood's capacity to carry life-sustaining oxygen to our brains and muscles. The symptoms starting with shortness of breath, mild headaches and nausea, can lead to unconsciousness and death.
Chimney
A chimney is a structural column of masonry, including a number of flues,
Chimney Fan
An electrical unit that is fitted to the top of a chimney to overcome a lack of updraught cause by a flue that is too small, or restricted in height. Will not necessarily overcome the inadequacies of a poor fireplace design.
Chimney Stack
The chimneystack is the freestanding section of the chimney, above the roofline. Being exposed to the elements as is the part most liable to wear and tear. The wealthier the owner the more elaborate the chimneystack.
Chimney pot
The chimney pot was originally a decorative terminal to the chimney and the degree of ornateness reflected the wealth of the owner (see Hampton Court Palace (London). Many early chimneys would have been built without chimney pots, which only became fashionable in the mid 19th century.
Condensation
Occurs when the temperature of a moist gas falls below the dew point temperature, at which level the moisture begins to form as droplets. Most noticeable on surfaces whose temperature is below dew point.
Condensing boiler
Modern generation of boilers, usually gas fired, where the boiler efficiency has been increased by using the waste heat in the flue gases. They have a very low flue gas temperature and require an insulated drained flue.
Cowls
There are many types of cowls and they serve several functions.
• to keep the rain out of the chimney
• to keep birds out of the chimney
Test have shown that the effectiveness of cowls to increase the up-draught and to eliminate downdraft is very limited and unless the cause of the problem is known, the appropriate cowl cannot be selected.
Dew Point
The temperature at which the moisture in a gas commences to form droplets. The temperature varies according to the type of gas, and the moisture concentration.
Flaunching
The flaunching is the weatherproof top of a masonry chimney (often concrete) which sheds the rainwater off the top. It is also used to secure the chimney pots.
Flue
Separate compartment within a chimney. A chimney may have several flues. Every fireplace (and/or appliance) should have its own flue within the chimney. Each flue should be gas tight.
Flue pipe
The pipe connecting a closed burning appliance to the flue. Usually cast iron, stainless steel, or vitreous enamelled steel.
Furnaces
American terminology for boiler
Gather
The gather is located above the open fire, and (as its name implies) gathers the smoke into the flue.
Inglenook
A very large traditional open fire in which the fire was continually burning on the hearth, which formed the prime heat source in the house as well as the place for cooking. The flue from the inglenook was un- throated and possibly 80% of the heat was lost up the flue.
Mid-feathers
The traditional chimney is divided into the various flues with mid feathers built of brick, stone, or slate. The mid-feathers are often the first unit in the chimney to fail as generally they are not tied in to the rest of the chimney structure and will collapse.
NACLE
The National Associatiaon of Chimney Lining Engineers (U K)
NACS
The National Association of Chimney Sweeps (UK)
Oversailing
The head of a chimney has both a visual and functional purpose. It is designed to prevent the rainwater falling on the chimney from running down the face of the chimneystack. If the water runs down the face of the stack it will quickly wash out the mortar leaving the chimney un-sound.
Parging (pargetting)
Because it was always very difficult to ensure that masonry was gas tight, the mason parged or rendered the flues using a traditional mixture of cow dung and lime. This was more recently replaced by a lime/cement/sand mix, which has itself been replaced by the requirement for all flues to be lined in new buildings in the UK from 1965 onwards.
Register plate
Used where a stove or boiler is installed into a traditional chimney. It is the closing plate installed at the base of the flue registering the position of the flue pipe. It prevents heat loss up the flue and air from the room being drawn up the flue. It should be gas tight.
Romford Fireplaces
A design of fireplace introduced into the UK in the early part of the 19th century by Count Romford (self-styled) whose paper to the Royal Society drew attention to the fact that fireplaces improved ventilation in rooms thereby reducing illness. His design included shaping the back of the fireplace and it introduced a throat to reduce heat loss and a smoke shelf. It is still common today in some fireplace designs.
Smoke Shelf
The smoke shelf is located above the throat and is designed to prevent down moving cold air affecting the outlet from the fireplace.
Soot door
The access door into the flue for sweeping, also known as a sweeping hatch. Should be located to allow any debris falling down the chimney to be removed.
Stove
Closed burning appliance designed for local space heating - can burn any fuel.
Sweeping hatch - See soot door
Throat
The throat is located immediately above the opening of fireplace. It is designed to restrict the heat loss up the flue. In sophisticated designs the throat can incorporate a damper mechanism to adjust the area to best suit the circumstances of that time (e.g. to close it completely when not in use).
Withes
Another name for mid-feathers (see above) |