building a cabinet door, wierd question?

[Josh Goldsmith]

I am getting ready for some refacing cabinets for my brother-in-law and was curious how much more " do you add for the resces hinges. I hope i am making sence. If your opening is 18" wide x 20" High how much more do you normally add to the height and width. Thanks Josh

[Steve Clardy]

I do a standard 1/2 overlay all the time. If you are using 1/2 overlay hinges, on a single door, ad 1" to width and length.