I do heating work and i have used light chains like you have to mark the location of the zone valves that were down in the blow en insulation. Then i would put a tag on the chain
that would tell me what that zone go to. Your ceiling joist are not 2x4 are they? I have been in attics where the had 2x4 and the bend real easy. Just wondered if they are there
to hold up ceiling joist. Is there snow on on the roof that would let the roof sag and make the chains lose?