I am looking for advice on a leak that I believe is coming from our roof. Sorry in advance for the lengthy post, but I want to include as much detail as possible.
About a year and a half ago, I noticed some drips in the basement at the base of our chimney. They looked like drops of oil. I then noticed spots on the wall and ceiling of our second floor (the ceiling just beneith our attic). I had a chimney sweep come out, clean our chimney and install a stainless steel liner. Turns out that the house we bought didn't have one (it was built in 1928 so for all I know, it has never had one). That seemed to do the trick. About four or five months later, I noticed the hardwood floor was damp on the second story...about two feet from where the chimeny runs up through the house. My thought was that it is still leaking because what was coming up throught the flooring did not appear to be damp/dirty water, but that oily feeling substance. I figured water was still running down the chimeny and working it's way out at one point and then along the subfloor. They came back out and tore down the chimney below the roof line (it was it terrible shape and had been poorly patched with concrete) and instead of having it rebuilt, I had them install a stainless steel bvent. That was done last October/November. Now, just last week, the floor was damp again with no evidence anywhere else. Now, this is a house that had plaster and in most cases, the person who renovated our house covered it with 1/4 inch drywall, so it does make a little sense that the water isn't appearing through the wall or ceiling. The rest of the floor in the room is in great shape, so I don't think the water could be coming from anywhere else. The windows are original, but the flashing and caulk is intact without any cracks. I figured my best bet would be to go into the attic. I went up and I do see some water stains around the wood that is around where the old chimney is, but nothing at this point seemed wet at the moment, but it was two days later so could have dried. The rest of the attic and roof for that matter looks incredibly dry. My guess is that my only option is to wait for a strong storm and climb up there and wait to see if I can find a drip. My roof it too steep to climb myself and hold a hose to see if I can find it before it rains. I really don't want to tear up the floor just yet. I would rather try to see if there is a leak in the attic/roof first. If not, I guess I would have to tear up the floor to investigate the subfloor to see if I can follow a trail. Does anyone have any other suggestions? Is there any sort of product that can help pinpoint a leak or somehow let me know if the water damage on the wood is old or or actually ongoing? The wood still seems structurally sound. Any thoughts or comments are appreciated. Thank you.