Metchosin - Securing the water heater is a good idea, but don't get the plumber to do it unless he knows how to do because it may worsen the situation. Esentially, the tank exterior, if cylindrical, should be braced vertically about the circumference and the strapping should be placed at least at the upper and lower quarter points. The tank should be butressed to the foundation wall. Braces and butress should be wooden or similar, to absorb some crushing. The straps should be designed based on the mass of the tank and contents in order to resist .... I am sure that there is some info on a government website somewhere that would have some details, but I think you can see why I have some trepidation about a plumber starpping it down. I know it sounds like I am making a big deal out of it, but in my 25 years in engineering and construction I have come to realize that everybody knows how to to everthing better than an engineer except stamping and signing the drawings.

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