Inserted chimneys (cassette) are a good heating method, with a cheaper installation costs than any other system. It also has the advantage of heating the home in a faster way than other systems. So it is very interesting for homes with sporadic, weekend use. The open chimney has a very low energy efficiency, and its use is uncomfortable due to the smoke and the dirt that emits to the house. The insert fireplace has a glass door that allows people to see and enjoy the fire, with a minimal emission of dirt and smoke to the house.
If you have an open fireplace made of stone or other material, the adaptation of a fireplace or casete insertable is not very expensive and the installation is very fast. More, in the link bellow.

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