ANSIO 94610 Interior Dehumidifier, 500 ml, Pack of 5 for £7 - DAMP CRYSTALS
We have a caravan here and inevitably in the cooler weather damp becomes a problem. Throwing a gentle warmth at the issue helps but a constant power supply nearby becomes critical to keep down the potential cost of unconnected heating options.

We've run around with damp and mildew sprays to fix the build-up but this feels a bit like locking the stable door after the horse has bolted! Of course a fresh flow of air is good, so if windows can be opened on sunny days, it can help.

But in spite of all the above, we still seem to get damp. And this, no doubt applies to all sorts of other situations of temporary or low-level damp in sheds, garage-bedrooms, out-houses etc. which don't really need or justify £100 on a dehumidifier. Assuming a power supply to run it.

Enter the Damp Crystals! I was sceptical as they seem so simple and cheap. The theory is that the crystals suck moisture from the air and as they dissolve, deposit the moisture in a trap underneath. Like salt or rice will do, but these seem more efficient and genuinely do seem to work.

Of course, they don't last forever, don't fix a serious damp issue and need replacing every 6 weeks or so, but for keeping a lid on a small but consistent issue, they seem to work a treat. We put all 5 of these around the caravan and sure enough, the damp has been collected and evidence of mildew around windows has gone.

They won't fix every problem and a certain amount of trial and error is needed, but as they're so cheap it's worth a crack before a more expensive and power-hungry solution is considered. Recommended for a trial.
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