This particular barn has been converted from it's once hay barn storage days to a building with multiple group rooms, with all facilities necessary for large groups to come and to hang out.  2 1/2" of Spray foam was applied to all exterior walls for an increase in R-Value of 15.7.   When we started foaming this project right before Thanksgiving, the metal roof just kept sweating b/c of the temperature changes.  We had 2 bullet heaters running full blast to warm up the building but the heat was just not enough.  Today, this building has an incredible "conditioned" feel to it Spring, Summer, Fall and Winter as all that is needed to warm up this building is a small propane heater.    The big ones that are typically installed in a space like this were WAY TOO WARM.  The Roof does not rumble anymore, the floor b/w the lower section and upper was shimmed up and to be level and foamed in between for noise reduction.  We also foamed the new joists to the old so that it would stiffen up the floor and eliminate the bounce that you would get with a 48 x 24 floor.  The owner of the building is highly impressed with the foam insulation.