Mature enough?

[Anonymous]

I have read in various places, here included, that lime putty should be matured for a while before being used. How long the lime should be left seems to be open to some debate though- a month...six months...a year?
Now, whilst digging up my front room floor I unearthed fist-sized lumps of the purest white lime putty, as wet as when it got dropped there in 1895. Is this just about ready to use then?

 

[Anonymous]

I've been maturing nicely for 63 years. However, the present Mrs Penrose says I exceeded my shelf life 40 years ago.

Maybe in my next life I'll come back as lime putty.

 

[Anonymous]

Bits of me are beautifully mature - chalky white and rather squidgy.
Apropos the lime putty, though; I'd leave it a while longer, You don't want to be using it too green.

 

[Anonymous]

Gervase, could you give me a bit of advice?
My daughter's thatched house has a coat of rough and grubby but sound lime plaster applied directly on to the underside of the thatch, between the rafters in the attic. She wants to convert the (large) attic into a room - would a competent lime plasterer be able to put a fresh skim of lime plaster over the old stuff, just to smotth and clean it all up a bit?

 

[Anonymous]

I don't see why not - if it's like most thatch it'll be pretty hard and not liable to deflect or flex when being plastered, and provided the existing stuff is rough enough and wetted enough, a new skim should key. In that sense it's no different to putting a second coat over a scratch coat on clay board or reed matting.
However (because there's always a but!), that presupposes that the thatch is in good nick, and if it isn't, that your daughter doesn't mind losing her attic room ceiling should it have to be replaced.
As a caveat, I should say that I'm not a thatch afficionado, and there could be a case to be made for having as free a circulation of air as you can around the thatch to prevent rot. One has to wonder if the plaster was put there originally to hide something 'orrible. If I were you, I'd badger a thatcher before hiring a plasterer.

 

[Anonymous]

OK - thanks for your views on that, Gervase. Actually the thatch looks as though it's in good condition, and certainly the underside that has already been lime plastered is good and solid - no hint of "liveness" in it. However, I take your point about air circulation, so I'm going to post a new thread on this to see if any thatchers will oblige with their views.
Thanks again.