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Obviously that is a personal choice in reality but in the UK certainly a lot of front door and garage door colours tend to follow the colours for windows. Garage doors tend to follow front food and window trends but of course you can select contrasting colours for the garage door.
A dark colour facing directly south isn’t the best idea so look for lighter colours if this is the case.
There are so many colours available now you can think modern, heritage, classic and matching, all depending on what your house is like.
The higher selling colours in the UK are tendon to be lighter greys, black, anthracite and white still but there are some beautiful muted and heritage colours for more classic garage door designs now which look great on the right houses.
Many garage doors have a white or very light grey for the inside finish to keep the light levels up inside the garage. This is worth checking on double doors as a black internal colour could suck a lot of light out of your garage if you are using it regularly.