I have a Water Softener which uses tablet salt so I have plenty of salt available. I have a problem with my loft (attic) in that it is constantly very damp. I've noticed that salt seems to be able to draw moisture from the surrounding air, spontaneously forming a salt-solution.

I'm wondering if I can rig-up a device a bit like one of those low-tech (Chemical) dehumidifiers: enter image description here where the resulting salt solution is captured in a vessel and I can then empty the solution into the softener - getting 2 functions from one bag of salt. The softener actually requires brine to regenerate the resin-bed so it relies upon steeping the salt tablets in a controlled amount of water and it then sucks that up during the regeneration.

1) Will this work?

2) Can anyone see any potential problems?

3) Any suggestions for building the device?

  • Not many people showing an interest inthis but here's an update for the 2 that have. About 2 months ago, I started an experiment by putting a kitchen sieve full of salt above an empty bucket in the attic. So far, there is not the slightest sign that water is condensing on the salt at all. It has not ben very damp weather during that period, but it's not looking hopeful as a dehumidification method.
    – Lefty
    Mar 24, 2015 at 12:46

2 Answers 2


I' think what you are saying is you want to use the salt to dehumidify the air, the idea that the salt will turn into some sort of slurry you can feed into your water softener. I'm not sure whether you want the salt to soak up the moisture all by itself, or use an electrical dehumidifier to pull the water out then then use the salt to soak up the water that way.

Either way this isn't likely to work well for you. The amount of moisture the salt will soak up is not going to be enough to dehumidify your loft (attic I'm assuming). It will simply cake up and be hard to feed into your water softener.

If you use the output from a dehumidifier add water to your salt you will need to modify your water softener (voiding warranties and support agreements), and develop a way to automatically put just the right amount of water into your salt so that your water softener will work properly while disposing of the rest. You then have a makeshift plumbing system with a large tank of corrosive salt water ready to leak all over your house from the top. Try explaining that in your insurance claim.

If you have damp problems I'd attack that issue directly.

  • You're missing the point, maybe I need to clarify in the question. I WANT the salt to soak up moisture from the air and turn into brine - then I use the BRINE in the Softener instead of/alongside tablets/ I therefore dehumidify my loft for FREE.
    – Lefty
    Jan 13, 2015 at 15:55
  • In that case an edit on both our parts would be in order. You may want to define loft as well (loft = attic)
    – GdD
    Jan 13, 2015 at 16:27

After so many years this may have already been answered, but here goes. Rock salt is your best bet for a salt dehumidifier. Unfortunately it is not advisable to use rock salt in your water softener, so the answer to your question (which by now you already know) is no. Soft water salt is not ideal as a dehumidifying salt. Rock salt (and the water it collected) is also a great weed killer as well as a de-icer, so it would not be a bad additional investment.

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