Hi all

I found someone not too far from me giving away 8 bags of base coat lime plaster for free after recent renovation work. It's bagged and ready mixed by the looks of it, seems a shame to let it go to waste, but I think its been stored in her garden and subsequently exposed to the elements. If this is the case and its suffered a few freeze / thaw cycles is this going to still be usable?

I guess materials get left exposed on site all the time, although so much in winter.

P

I think it can be reused simply by mixing it up again. Takes years to fully recarbonate.

Hydraulic lime sets by chemical action when exposed to water. It needs to be sealed in waterproof bags. Air lime by contrast can be left for years and when kept as putty it improves with age for quite a while. See e.g. https://www.ecomerchant.co.uk/news/whats-the-difference-between-hydraulic-and-non-hydraulic-lime/ for more information.

So if it's free and seems like it hasn't set in the bags then it might be fine. But if there are lumps then it's probably had it I suspect. Freezing shouldn't affect it provided the bags are sealed I'd have thought.