Leak near radon vent in basement

Yesterday I noticed a leak in the middle of my basement, right where my radon vent enters the ceiling (see picture titled ‘Basement View - Note leak right of vent.jpg’). This is a passive radon system and the vent continues through the 1st and 2nd floor, into the attic and through the roof. It has rained moderately for the last three days.

I initially thought that I may have a roof leak, but when I inspected the vent in the attic I found no evidence of leakage. The exterior of the vent was dry (see pictures titled ‘Attic View #1 - Radon Vent on Left.jpg’ and ‘Attic View #2 - Radon Vent on Right.jpg’). The leak in the basement is located directly below the #1 attic picture, where the vent exits the attic floor. Since the radon vent bends 45° upon entering the attic from the basement (Picture #1), and then bends again 45° before exiting to the roof (Picture #2), a roof leak should be located at the second 45° near the attic ceiling, not the floor.

When I looked at the exterior of my roof, I noticed that neither the radon vent nor the plumbing vent stack had a cap on it (Roof View - Radon Vent on Left.jpg). This leads me to conclude that the rain water is running into my radon vent and somehow finding a way out after the vent descends below the attic floor. Does anyone else have another plausible reason for this leak?

If this is indeed the cause, can I just put a rain cap on the vent or should I try and find the leak somewhere between the basement and attic? The vent appears to run through a second floor utility closet (2nd floor) and a coat closet (1st floor) but I hate to have the rip up the sheetrock if I don’t have too.

I’d appreciate any thoughts on my predicament.
Thanks

Mesa1987

If there is no leak on the exterior of the pipe there may be a fitting that is not glued up right and the rain water falling into the pipe is finding its way out through the hub.

Unless there is another source such as a leak elsewhere dripping on the pipe then all I could suggest is that the pipe is sweating which might happen in cold damp weather.

Thanks,


If the pipe is sweating, do you have any suggestions on how I could resolve it?

I live in Greenville, SC. I just checked the rain over the last two weeks. We got 1.5†on 22 Dec, 1.3†on Christmas day and .62†New Years eve (last night). I first noticed the leak on 30 Dec when I was cleaning out a section of the basement in preparation for a renovation (obviously on hold until I can resolve this leak).

wrap insulation around it... that's what the HVAC folks do to stop ductwork from sweating.