A. Harrison McCampbell, an architect and moisture-intrusion consultant in Brentwood, Tenn., responds: Your concern about through-fastening is justified - it makes little sense to apply a carefully waterproofed membrane and then poke it full of holes.
It is technically possible to put a railing on the roof that is held in place by gravity alone. A simple way to do that would be to weld each of the railing columns to steel base plates. But first check your local code to make sure that the area where the railing will go is clearly defined as a roof, not a deck. This will probably depend on how...
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