We got a new door for our old garage. It wasn’t replacing the originals, but was replacing a 50 year old door and opener. We’re very happy with the new, quiet door but it is insulated and does make the garage hotter.

So I think I had the exact same door(s). They were heavy, falling apart because of the rain hitting the driveway and splashing up, and didn't fit well.

I re-framed the two smaller doors into one larger door and installed steel insulated door.

It was a huge improvement.

I've had aging, deteriorated garage doors replaced. I'm not convinced that the new steel doors will last as long as the old wood ones did. However, I can't deny that, for now, they fit better. Among other advantages, that helps to keep the little critters out.

You can order a new overhead door with an extra thick bottom seal, which can help to compensate for some unevenness in your floor. But that can only go so far. For really good results, you'll need to get that floor fixed.

For the summer heat problem, have a ridge vent installed. If that's not enough, you may need to add a thermostatically controlled gable vent fan. Note that a tighter door may actually reduce the amount of cool air entering to replace the hot air that exits via the ridge vent or fan.

Thank you all. Is there nothing that can be applied to the door to reflect heat? I assume that the pretty windows on some decorative doors would increase the heat problem.

The heat in my garage comes from sun on the roof, not the door, so I guess that is a different situation from yours. The door is insulated and keeps that heat in. Perhaps it would keep heat out if the sun hit it.

I’m not sure if these need to be replaced or if they could be repaired.

Door looks OK on the inside but that doesn't tell us much. Need exterior photo.

Is the attic over the garage insulated?

That door looks exactly like the one my parents had in a 1959 built house, except theirs is a single garage. That single door was so heavy. They did have a garage door opener for a while but was the dangerous kind that had no safety stop. They had a new modern metal, insulated door installed with the safety feature. They probably sell garage door gaskets that can be installed on floor ( standard comes with on on bottom of door) they do have a gasket/trim, with a rubber edge,that goes on sides and top. The heat I'm sure is just sun on roof, possibly no ventilation. A new insulated door won't make it better.

Garage door openers have a adjustment to how far down the door goes when closing so it will not be resting/stopping when it hits floor. So the gasket bar bottom of door isn't totally squished down. I usually try to remember to put some sort of lub on gasket before winter so ice doesn't stick and freeze gasket to floor.

Weird. I added these two pictures on the first post but only the interior one posted. I’m pretty sure the attic over the garage is insulated with the pink insulation as I store tomato cages there in the winter. R8 comes to mind? So I’ll give up on the hope of a cooler garage.

But to tell you how bad it is, some organic fertilizer concentrate exploded when I opened it even though it was in cool weather. It had bulged out in the heat I guess, just waiting for me to spew it all over my white kitchen cabinets., LOL. I will never open anything like that inside my house again. And when something is bulging, I will know I’m in trouble.

The garage was likely added on in the 70s. That’s an educated guess When I moved in 18 yrs ago, the left-hand garage door did not have a remote capability so I added that on. But it’s kind of funny because the old one is much faster, more reliable and quieter than the new one. Newer is not always better. But both doors are the same age. I have no idea how old they are. Definitely need a new coat of paint at least

I am not a pro, but rather an experienced DIYer.

Garage doors for the most part are NOT a DIY project. Contact a couple of GD installers and see what they say.

As to how old garage doors can last? You have been there almost 18 years, correct? The life of those doors is 18 years and 1 month.

It seems the Garage is attached, if so, you will notice less drafts coming into the house from the garage WHEN you replace the doors.

If you take a look at your initial post, you pretty much answered your own question with this line. "My garage doors are looking quite dilapidated." Would you spend money on fixing something that is dilapidated only to have to redo it in the near future?

Something to think about is reflective barrier like this

DavidR has some great ideas. Especially venting the garage. In order to keep the garage cooler, you need to get the heat out. Also, as he mentioned, you can get garage doors with thicker bottom seals. You can also get a threshold seal like this.