I have just installed an 'inset logburner' and in doing so have had to remove/cut in to quite a few of the bricks that the fireplace was built of and intend to render over the fireplace and then colourwash it in order to hide the damaged bricks and also make it fit in with the room decoration. Question! If I use a standard Sand/Cement/Lime render in the 5/1/1 mix do I need to do anything to ensure that it wont crack due to the heat from the fire (it's 5kw)