I recommend contacting Hardi and asking for their advice. Their contact number is 1-888-542-7343 tho you might have to go thru a phone tree before you get a hold of someone who can advise you. I suspect tho that the paint and mud can be removed by judicious scraping with a paint scraper. If the mud was as thick as you say, the scraper will probably only cut partway thru the mud layer so the Hardi shouldn't be harmed unless they really "dig" in. And, if the paint was just applied recently, it may still be somewhat "soft" especially where it was applied over mud so should come off easily. Once the paint layer is scraped off, they can clean off the rest of the mud off using a stiff bristled brush and a bucket of soapy water. I know they should NOT use a wire bristle brush or a pressure hose to clean the mud off because those things can damage Hardi. Once the Hardi is clean and dry, repaint and you probably won't ever be able to tell where the mud was. But, check with Hardi first because you don't want to let the GC do anything that may void your Hardi warranty. AND, once you have a plan of action, let your GC know in no uncertain terms (and in writing) that you want to inspect the Hardie after it is clean and BEFORE it is repainted. And furthermore that, if they gouge or damage any Hardi in the process of cleaning it, you will expect him to replace those boards at his expense. Individual Hardi planks CAN be removed and replaced although it is a PITA to do and takes a contractor who knows exactly what he is doing. We had to have several individual pieces of Hardiboard replaced on our house because the electrician our idiot builder hired cut holes to put place several exterior lights in the wrong locations (off by several feet!) even though the proper locations were VERY clearly marked on the plans. While I can understand that the painters get paid only to paint (and not to clean off mud spatters before they paint) ya gotta wonder just how dumb the painting subs were that they would just paint right over the top of a thick coat of clearly splattered on mud instead of at least ASKING first if the GC didn't want to clean it off before they painted. On the other hand, they probably get paid by the hour and now your GC will have to pay them to come back and redo the paint job. Good luck. If this is the worst nightmare you've faced your building, you've gotten off very easy.

Just another thought if you want to go the hair dryer route is to get one of those hand held heat blowers that look like the hair dryers from a construction store. Forgot what they are called at the moment. They work just like a hair dryer on steroids so that should move your heating a scraping along a little faster. Use caution as these can blow some serious hot air that can cause a fire. Casey "http://www.driverdb.com/Sean McDonagh"

Hey MC, Flats have no "sheen" to resist moisture penetration/cleaning. I'm glad you got a "Satin category" paint! Cheaper Flats don't have as much pigment in them, & the binders are lower-quality as well. >>> Translation...even when cured, cheap flats don't hold pigment/binder very well when scrubbed/washed. Faron

Graywings, I wrote a white paper on the subject. It's kind of involved. We'll start with one question. Does the human fovea have corners? Nope. The fovea is literally the center of all color vision - it's where the magic happens and the sensation of color vision spreads from there. "The eye's sharpest and most brilliantly colored vision occurs when light is focused on the tiny dimple on the retina called the fovea centralis or macula. This region has exclusively cones and they are smaller and more closely paced than elsewhere on the retina." And, yes, the eyeball is continuously moving and adjusting to get the light to fall on this region -- eyeballs are constantly working to provide maximum visual conditions to support the eye-brain system for vision. The circle is ergonomically more accommodating to our physical vision system than a square. It's like shoes. You can wear four inch heels. They will get you around and where you need to go. But tennis shoes are a lot more comfortable and less physically taxing on your bipedal system - you can walk more efficiently, farther and longer in a pair of tennis shoes than you can a pair of heels. There are so many things going on when we are working to choose paint colors that sometimes even the smallest things can make a difference. There is an ease and friendliness about a circle and it literally takes the edge off what can be a taxing task. Then there's the argument of boundaries. As my friend Niki Fulton describes it, "Squares have fairly rigid boundaries and seem to contain the colour inside their shape. Circles on the other hand do not have such rigid boundaries and do not constrain the colour within them. They seem to allow the colour to radiate from the circle and make it much easier to imagine a larger space painted in the colour of the swatch." Here is a link that might be useful: cite the source