mouldy daub

[k99mn]

Hi, about three weeks ago i replaced a damaged daub internal wall panel, just gone to plaster same and noticed its going mouldy, anybody any ideas as to why? and how can i stop /cure it before plastering
k99mn

 

[skier-hughes]

What exactly did you replace it with?

 

[Flyfisher]

My understanding is that mould usually means condensation because it's fresh water rather than 'salty' damp caused by migration of water through bricks and mortar, which is likely to be caused by the new material creating a cold patch where there wasn't one previously. Skier's question is a good one for understanding if this is likely to be a temporary problem or something more serious.

 

[formerly known as]

in my experience, clay work (using recycled daub or clay lump) will show surface mould if it is done during colder weather. Wait for it to dry and simply brush it off. Nothing to worry about.

 

[Penners]

Interesting and informed answers above. For my own edification, would it cause any harm to the plaster if it were wiped over with mild solution of bleach?

 

[formerly known as]

Simply no need to use the bleach Penners. Remember that historic clay products may contain all sorts of associated inclusion/s from either the subsoil or from the 'machinery' that might have trod it. Clay work over the colder months takes longer to dry, so shrinks far less, but can be prone to becoming mouldy. Reconstituting clay and adding lime will reduce the growth. It is not uncommon to see signs of surface mould between daub and plaster coats on old work - probably indicating autumn winter work (I am of course referring to internal work).

 

[formerly known as]

k99mn must have been consumed.

 

[Penners]

with something, or by something?

 

[formerly known as]

I recall the film 'the thing' ..... perhaps the mould was merely embryonic.