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You need a curb that extends above the roof level or water will run right into your hatch every time it rains. If you make you deck high enough it could be flush with the top of the hatch
the deck will be 12 inches above the roof. wondering whether there are other issues that need to be considered such as safety
If you frame the deck and the hatch properly then you shouldn't have any safety problems
Ok thanks Rick. Very helpful
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