Build Like a Pro: Should I Flash an Exterior Door Under a Covered Porch?

flashing a door
If you want to remodel like a pro, I suggest you do what the pros do. For inspiration, many professional contractors hang out at the online forums of

This is the website of the highly respected Journal of Light Construction.

To participate in the forums, you have to be a professional contractor. However, DIYers and homeowners are welcome to read and learn.

Here’s a question that was posed recently under the Exterior Details forum:

What is the standard in terms of flashing an exterior door when it’s completely under a covered porch. Early 1900’s home. Door is set in about 3′ from the closest side so potentially some seriously sideways rain, maybe? But could I get by with just good caulk behind trim and under sill, spray foam gap from inside and call it good?

Now, notice that the two suggestions offered by other contractors look into the future of the house, not just what will work in the moment.

Answer #1:

Treat it like a regular door. The house may be powerwashed one day.

Answer #2:

Agreed. Don’t skip any protection under the assumption the door won’t see weather. That porch could be a thing of the past one day, but the door might remain.

In my opinion, looking into the future and building right for all those eventualities is the key to building like a pro. Some of this carefulness is driven by the desire to reduce future liability when things fail on a house. But it’s also the basic desire, which we all should have, to build something that will last.