well there are two different materials that garage doors are commonly made of and that is sheet metal or steel and of course wood. If your garage door is constructed of wood and it has a crack in a panel then it would probably be a lot easier to fix than a steel garage door that has developed a crack. When you are dealing with wood garage door sections fixing a crack in As easy as adding a piece of wood on the inside of the door and using some screws to mend the crack or split in the wood. Or even maybe using a flat piece of sheet metal and Drilling holes in the sheet-metal and screwing in some wood screws to hold the two pieces of wood that are separating together Again.
woodpaneled garage door
When a woodpaneled garage door develops cracks or separation in the panels construction then it is usually from age and or climate depending on what region you live in. Custom-made wood carriage House garage doors usually when they are quality constructed they are made with what is called marine grade wood. Marine grade wood is wood that is made to withstand elements like the wood you would find on a boat. Marine grade would when finished properly with the right finishing material will last a lot longer than any other non-marine grade wood like pine or oak. Now if you are dealing with a steel panel garage door then fixing cracks is not very easy because you would have to have some knowledge of working with sheet-metal and or knowledge of auto body work.
steel garage door
When a steel garage door developing cracks on the panels then it is for a couple of reasons if the panels on the bottom of the garage door are developing cracks then it is most likely because it has been damaged and or hit by a vehicle or something of that nature. I have even seen a door develop cracks from being constantly hit by a basketball because there is a basketball rim that is on the roof of a garage and kids will not open the garage door when they are playing basketball and when the basketball is constantly hitting the garage door panels and denting them it can cause the panels to crack. If the crack in your garage door panels is on the top panel and in the middle of the garage door it is most likely because the garage door opener has pulled back on the top panel for so long without any reinforcement that it causes the top panel to split in half or bend and eventually just crack In 2.
rain pours into the garage door?
If you just have a small crack and when it rains water comes into the garage door then you could probably use some caulking to fix any water leaking in but if you are going to try to repair a crack in a garage door it would be much cheaper to just have a panel replaced. You also have to remember if you were trying to seal or fix a crack in a garage door whether it is wood or metal that a garage door has a lot of moving parts and it is self moves up and down and fixing a crack in something like that is very difficult.