ive completed my build now deciding to go against chinmey through wooden roof as too problematical and to be honest i dint need a chimney, fire draws and burns up to 800-900 degrees as best i can make out ( two broken thermometers ) but I would like to add a decorative coat of masons or lime render which i hope witll give a nice smooth and attractive fisnig, much liek plaster. my question is has anyone on her had experience with using it as ive heard it a bit volatile? thanks
These guys are the best for "off the shelf" products. They'll even do a waterproofed version, although there are additives and traditional methods too. They are incredibly helpful, and knowledgeable. Just drop them a line!
Just wear gloves, and wash off any splashes on the skin. Its more alkaline and causes burns along the lines of cement. I now prefer Limes for brickwork, over OPC. Well...most advocate the addition of Hydrated Lime to Cement based mortars to make them more workable. That makes me wonder that Cement is an inferior product, as it needs additives to make it more user friendly.
As Danno says, I used hydraulic lime render over the top of my clay oven, and found it to be very easy to work with. Admittedly, I've never used cement render - but on the basis of how easy lime was to work with, I'll certainly use it again in future. The stuff I used also came ready pigmented.
I can't yet tell you how hardwearing it is, because shortly after I rendered my oven I was called back offshore. Probably a good thing, as otherwise I'd have been tempted to the oven up before the lime had cured.
Cost £12 a 25kg bag if I recall correctly - more expensive than cement render, and 'readymix' is a bit of a misnomer because the lime comes in a separate bag. Doesn't take long to mix it up in a wheelbarrow though, and lime being lime, if you don't manage to use it all one day, chances are it will still be workable the following morning.
No more using portland cement for this oven builder, no Sir!