Time was when every farm would have had its own malthouse-an outbuilding where the barley grains would be put on racks to sprout, and then spread out on the floor below to dry to make malt. As in "This is the malt that lay in the house that Jack built". And what was the malt for? Why ale, of course! The Agricultural Revolution didn't change the need for malt houses, but when the traditional areas stopped growing barley, the malthouses were often converted to other uses. With the growth of the railway system in the 1830's, they started building big commercial malting premises near to the railway stations, and farm malthouses gradually fell into disuse. The caption for this particular malthouse, which is from the lovely Geograph site again, says that it's the only one left in Somerset. I'm surprised that it exists at all, quite frankly.Not all of this building is a malthouse- I'm sure it's just the bit on the far end with no windows and an outside set of steps.
There isn't any particular relevance to Jane Austen about this particular site, although you could imagine Col. Brandon's estate having farms like this, if you like. Or alternatively, you could imagine it belonging to the "Person from Porlock " who so rudely interrrupted Coleridge when he was daydreaming about Kubla Khan, thus depriving the world of a great epic poem....
