Dymalica
Mechanical
- May 4, 2007
- 43
For rooftop ductwork, what is the best way and cheapest way to support a duct in a seismic zone such as california? Lets say the duct is 30x30. Is the best way to do it to get a flat block and lag bolt it into a roof joist? Then stick the tube steel support on top of the flat block and connect the tube steels with angles? I am trying to avoid welding because that requires special inspection. Then install the roofing over the block with a steel skirt around the tube. I know most people just stick a block on the roof and mastic it on the bottom and then put the supports on the block. I don't think that flys in California anymore. What do you think?