Yikes!

Looks like you need a strip of drywall and a run of weather stripping attached to that. Then you need some foam core to drop into the aluminum slots in the door — this helps a LOT to prevent heat loss in the winter and heat gain in the summer. Last thing if you don’t have it is weather stripping down the sides of the opening.

I can't tell what's going on here, but "pink insulation", or any fiber/ stranded insulation don't block air. it has r value but you'll still be promoting air exchange. you'll most likely want a foam, whether that's rigid board or spray, or both. there's other ways to block air transfer, but it depends on construction.

I can't tell if that's a dimensional rift, foil, or missing drywall

Is there a gap where air passes thru at the top edge?

I had a gap and by careful adjustment of the down-limit, I got some more pressure on the door and most of the gap was closed. That's the fastest thing you can do in this weather.

Then I got that garage weatherstrip and used rivets and little washers to hold the weatherstrip on just right. I did mine in the summertime and I can't imagine trying to do it in the cold.

I'm trying to think of a fast way to do something.

You might use doublesided carpet tape to affix some insulation up there.

If you have some steel up there and a bunch of magnets, maybe you could do something that way.

Everyone talking about the gap but nothing about the huge problem you now have.

Aluminum doors are a big ole 0 for insulation. They let cold and heat through them like they arent even there. You need to look into some insulation boards for them and install. That will definitely help with the cold in the garage.

Much appreciated. I am still confused as to why they sheared off so much of the old drywall. Thanks for the tips!

Much appreciated. I'm still not sure why they carved that old drywall out. The gasket on the top of the door is making 90% contact but lets a lot of sunlight in so I'm at a loss on how to block that 1/16th of an inch properly without obstructing the door. I found two large holes leading to outside that I have filled with foam spray. I appreciate you taking a look!

I will need to google down-limit. Anything that has to do with adjusting a garage door freaks me out bc of that spring. What's odd is that the weather strip thats on there doesn't make full contact. There are also tons of cracks alongside the door that I will fill with caulk.

Your idea about doublesided carpet tape is brilliant! Thank you!

could they have used a clear caulk? if it's passing light and it's a separation, a quality caulk will fix your issue.

I still don't know what I'm lookin at. the pov/depth of pic is weird. but you can always cut back more drywall to place more material, whether that's wood, foam, combination of, more drywall. if you're getting air, it should be patched somehow.

I'm not sure if you're having a building siding issue or door seal issue at this point. it sounds like you're not sure either and it's confusing me so Consider:

if what you're getting here is light through the flap gasket, your door likely needs adjusted. this is usually as simple as [with the door closed] loosening the track brackets on left and right side and pushing the tracks further towards the gap closing it, and making sure nothing rubs excessively, or that you don't go too far pushing the seal out worse. this is assuming your seal is still pliable and positioned correctly to begin with. you may need to get a track grease if it's a significantly tighter fit/ door wear. seals may need replaced.

Definitely didn't use a clear caulk. I'm able to pass a putty knife through to the other side. Yeah I know the pov/depth seems weird but it's just a view from the top of the door. I posted a wider shot for less confusion.

The only air coming out on the top is where the door gasket is not reaching the drywall. I'm 100% sure that the issue is a combination of air coming in through the door as well as the siding of the building.

I'll have to give that adjustment a try. Thanks

This 100%. I've been looking at the insulation kits and will install them.

Actually, you may want to run a 2x4 or something else like that instead of drywall, since it appears to be fully exposed to the outside.

Maybe this door is slightly shorter than the old one was?