drywalling over cold air return chase
My return at the furnace has is spliced with the metal "joint" I believe you're referring to. I have seen it in runs between floor joists on occasion. Oldrivers has the right idea though with the metal tape on the joint after you take the spline out. You could also use tape to temporarily hold the actual metal to the joists until you get the drywall up. No need to replace the panheads that way.....
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