The fireplace has certainly changed since its original design so long ago. Improvements have been made since the primitive use of fire containing devices, one of the most recent of which being the factory built or prefabricated fireplace unit. A prefabricated unit, or prefab, is made of metal instead of brick or other masonry materials. A prefab uses insulation, pipes which are cooled by air, and blowers to move the heated air around the house. These systems are very sophisticated and manufactured and listed for use as a unit. Each part is approved by the Underwriters Laboratory to be used in a certain way under certain conditions with other parts that make up the unit.
A prefab doesn’t require a cement base for a foundation like a masonry unit due to how much lighter the prefab is. These systems have either cooling spaces in which air pockets act as insulation or actual insulation which allows the units to be closer to combustibles than would be otherwise.
Factory built fireplaces generally last until a part needs to be replaced but is no longer manufactured. At this time the prefabricated unit has reached the end of its useful life because it needs that specific part in order to be operated according to UL standards. They must be installed according to manufacturer’s instructions and is not easy to remove in order to conduct an inspection.
Never install a wood stove into a prefabricated unit, a prefab is meant to be operated according to the manufacturer’s instructions exactly. Similarly, it is not safe to burn paper waste in a prefabricated fireplace unit because of how hot these fires get and how quickly they get so hot. (Since its close to the holidays, please remember that it is not safe to burn your Christmas tree in a prefab either; it produces a similar effect to a paper waste fire.) Also, when operating your prefab, the damper must be completely open and should remain open until the fire is completely out. Prefabs require less clearance than other appliances and are easily to install in most areas of the home because they are so light weight.
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