Loud Bang that seems to be coming from Roof

For the last couple of nights I have been hearing loud thuds or bangs that seem to be coming from my roof. I live in a condo which has a flat roof and we have been getting a lot of snow and ice in New England this winter. My Condo Association said they were going to clean the roof off, but I’m worried that they might be too late. Any ideas what this could be?

Assuming it isn’t something dropping on the roof, it may possibly be the isocyanurate insulation board expanding and contracting. This has been cited numerous times by homeowners that hear cracking and other noises on their roof.

Hmmmm. Okay. Thanks alot. yeah I don’t think it’s something hitting the roof, since it’s happening in the middle of the night and it’s happening multiple times. Just wanted to make sure I wasn’t going to get crushed in my sleep. Thanks for the input.

Ive heard of this many times. No one has ever been able to explain it. It only happens with certain temperature changes. I think it may be some form of expansion & contraction in the truss/rafters.

Yes, every winter here, several homeowners ask the same question. One to two LOUD bangs several nights in a row coming from the roof area. Roof frame area.
Doesnt happen during the warmer months.