outdoor fireplace

[gay hennessy]

I would like to cover over an old stone and concrete fireplace/barbecue with a white plaster -it is currently an uneven surface because of the stone, narrower near the top of the chimney then at the bottom . I am interested in making it somewhat symmetrical - is there anything special that i should add to the plaster to make sure it adheres to the current surface, doesn't crack etc?

[Rich]

I would probably start with cleaning the stone/concrete with a stone cleaning agent. Then if it's really uneven you could probably use metal lath and wood to fir it out in the really bad areas and then apply the plaster to that. It should adhere very well.