A trombe wall is a passive solar building design where the wall is built on the winter sun side of a building with a glass external layer and a high heat capacity internal layer separated by a layer of air. This may seems complicated explained like this but when you’ll see the scheme bellow you’ll understand it better.  Modern trombe walls have vents added to the top and bottom on the interior side so it allows heated air to flow via convection into the interior of the building. The link will show you more.

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