A friend of mine called me up the other day and tried to gauge my interest in this project that he was considering. He was looking at this industrial building which had about 2500 sq. ft of floorspace. However the roof was thirty feet high and he was planning to add a second story. To be precise he wanted to know what I would think I would charge him for the job. It had some problems obviously. The building had asphalt roofing which had to be replaced, meaning that you had to remove everything that was on the roof and replace the lot of it. If you are lucky with such a roof then you can just put a new coat of asphalt on top of the old roof, but that had already been done as many times as you could safely do it. Obviously a roof or any other structure has a load capacity which can not be safely exceeded. Aside from the weight of the asphalt you have to consider how much burden a heavy snow would place on the roof. Obviously some snow is denser than other snow, but when you get right down to it snow is water and water weighs almost 9 pounds a gallon. I would not care to calculate how much 8 inches of snow is going to weigh, but it is a lot and you have to be ready for that. If you overburden the roof with asphalt or any other roofing component, then you are going to be making it more susceptible to failure when there is a big snow fall. At any rate I did not really have the time for this project in any near time. All of my men and all of my money are already tied up in other things.