Thanks to everyone for offering thoughts on my problem, and sorry for the delay in response. I borrowed a camera from work and got a few pictures. Some of the images are relevant to more than one response, but I’ll try to put them in a reasonably coherent order. It wasn’t much of a camera, and I’m not much of a photographer, but hopefully these help.
Here’s the outside of my house:
And here’s the damage:
Yes, I know I shouldn’t have let it mold like that. It was pretty advanced when my roommate showed it to me and I’ve been more concerned with fixing the root of the problem. I’ve cleaned it off since taking the picture.
Here’s a few shots of the roof over the trouble area:
There is a poorly-ventilated bathroom (which is to say, not at all ventilated) directly across the hall from the room where I’m currently having trouble. Are you saying that perhaps moisture is diffusing through the bathroom ceiling and then condensing above the trouble area?
Sometimes when they replace the pipe collars, A pvc joint loosens up. Plumbers are famous for not using glue in the attic. They figure it is only for venting. If you had a lazy plumber.
Could be the roofer did not know how to install the pipe collar.
Is the space heater kerosene? Does your roommate smoke or burn candles in the room?
The list goes on…
If it is only one spot, insulation would not be my first choice.[/quote]
The space heater is electric. My roommate does not smoke or burn candles. What effects might those things have? As for the pipe collar (I didn’t get a good image for this, sorry), there is a vent for the water heater and furnace (see below) that is not connected at all; there is ~1/2 an inch gap between the pipe and the outlet on the roof. That’s the only pipe up there, I believe. Is it bad that it’s not bonded tightly?
[quote=“shangle nailer”]You said the leaking is happening at the edges of the house-is most of the water damage showing up in the ceiling or the wall itself? I saw a house once that had several bad spots in the cornice work that funneled water into the soffits and saturated the wall inside.
I also think that condensation from hot air in the attic could be the problem, like GTP was saying. I would think when it was cold outside you could go in the attic and find it though, especially for the amount of water you seem to be talking about.
What pitch is the roof?[/quote]
The damage is pretty much coming in through the ceiling, and the trouble spot right now is in the middle of the house:
If it’s a cornice problem wouldn’t you expect it to come from the very edge of the house? I’m not positive of the pitch of the roof. I think it rises about 6 feet over maybe 15 feet, so… somewhere in the neighborhood of 20 degrees. Is that too shallow to be reasonable?
[quote=“tumpline”]Just thought I’d share a situation I came across last winter.
Homeowner called to say roof was leaking, roof was 4 years old and they noticed very slight staining on the ceiling a year before that but as it was just barely visible they didn’t think to much of it.At the time they called me it was clearly evident it was leaking.
That day it was -16 degrees celcius, and while driving there I was thinking it may be a ice damming problem, however I found no snow or ice on her roof.
Put up the ladder and was expecting to possibly find a few shingles had blown away. However the roof was in great shape and no visible damage or defects in that area.
Asked permission to go inside her attic to have a look, upon doing so noticed that she had blown in insulation and at the corner where the leak was happening the insulation had somehow blown off the vapor barrier completely an area approximately 6’ x 6’.I assume it was blown back by the smooth circular pattern that was left there.
A considerable amount of condensation had developed under the vapor barrier and was causing the leak.
I installed baffles at the soffit vents put back the insulation and have not heard from that customer again.[/quote]
Ok, this is a definite possibility. I crawled back to about where I think the damage was, and there was essentially bare roof right above the spot.
I hope this is not the source, because it could mean the other trouble spots I had are not cured by the new roof and all the trouble was caused by pulling the insulation back from the soffits. In any case, I re-covered that spot as best I could. It rained the other day (kind of early in the day) and there was no wetness in the corner when I got home in the evening, but that’s not conclusive. I guess I’ll hope that more weather comes along soon.
Again, thanks everyone for your comments!