I am trying to figure out the source of a wet spot that forms on my covered front porch right next to the outside wall of my home pretty much every time it is raining. This started only a few weeks ago and the spot dries up within a day. Water it not dripping down from above. The wall feels dry. There is a well ventilated open space beneath the porch. The house is 100+ years old. Any suggestions of what could be the cause of this are appreciated!

wet spot on patio

  • Are you 100% sure there are no leaks in the roof? Could it be due to driving rain? The most obvious answer when an outdoor area gets wet during rain is the rain :) – mmathis Mar 8 '17 at 21:26

If you are SURE nothing is dripping there, easily tested by placing a dish over the spot during and after a rain shower, then the spot is probably absorbing moisture from the air.

Something may have been spilled on the decking there that absorbs moisture better than the rest of the decking. Like a sugary or salty drink, or an animal secretion....

| improve this answer | |
  • 2
    From the shadows I see in the deck it looks like it is running down or horizontal on the trim. – Ed Beal Mar 8 '17 at 19:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.