DIYbanter - View Single Post - Moisture absorbing calcium chloride crystals

Robert Laws

wrote:
Ian Stirling wrote:

Does it actually reduce dampness at all?

from what I've seen of thesse things, they do absorb water vapour, but
the amount of absorption is only a small proportion of the damp
present, so they have approximately no effect on the situation. Theyre
basically junk products.

I have several dishes of calcium choride under the floor in my
narrowboat. it does keep it dry down there. But that it an
environment where new water vapour enters only slowly so only a small
amount of dehydration is needed.

As others have pointed out, calcium chloride is deliquessant, not
merely hygroscopic; it absorbs so much water that it completely
dissolves in it.

Robert