This is located in the kitchen, lounge, dining, bedroom or study.
In the olden days people used them for cooking or heating large amounts of water for bathing.
The chimney is designed with a flue which takes out the smoke through the roof and out of the room.
It should also have a fire back to protect the building fabric from heat.
Another important part is the hearth that collects the burned out ash.
The decorative piece above the opening is called a breast.
A smoky chimney has a lot of discomfort for the home owner.
This usually has smoke bellowing out into the room.
This should be going upwards after lighting a fire.
The design and size should correspond to the area of the room.
The designer should ensure the size of the openings are commensurate with the flue or stack.
When this is checked to be correct, then the home owner can carry out simple tests to stop the problem.
The mechanism of sucking up the smoke is the throat.
This allows the fire to stay lit and also carries out the smoke from the room upwards.
The tests for a smoky chimney involve checking whether trees are blocking the flue outside.
The tree branches should be cut or trimmed.
This may cause back flows into the flue.
Another test may involve checking the inside of the flue.
This should be free from fallen mortar or bricks during construction.
This blocks the stack leading to smoke drifting into the room.
A brush can also be used on flues that have soled brickwork.
This removes the soot lining and reducing the flue opening thus causing smoke to drift backwards.
A smoky chimney should be tested for openings.
This is up the stack and within the room.
The stack should have equal openings on either or all sides.
The final test involves using a sheet below the hearth to check the opening in relation to the flue.
It is done on a lit fireplace.
A sheet is lowered gradually reducing the open space below the hearth.
As soon as the smoke starts to rise into the flue, mark the point.
This is then built up with bricks to make it permanent.
Also the flue may be increased to add the height if blocking the opening is not possible.