Another Dryer Vent Conundrum

john620 · 03-05-2012, 09:09 AM

I need some help on a reroute for my dryer vent. Attached is a pic of the vent as is when I bought the house and current state. As a fix my original thought was to run the vent straight up and parallel to the floor joist and out the rim joist (instead of running below 4 joists and out the rim joist, as it is right now). The problem is a radon pipe the goes up in that space (pic attached). When the radon pipe was installed they but a block out of the rim joist to make it fit. My assumption is that it would not be good to add another 4" hole in the rim joist that close to the hole for the radon pipe.

Next thought was to run the pipe straight up and through the rim joist out the side of the house perpendicular to the floor joist. Problem here is a floor joist about 6" from the rim joist (pic attached). Everything I have read says do not put a 4" hole in a floor joist, so....

Any ideas anyone? The only thing I can think of is running the pipe up, 90 degrees below a few joists, 45 degrees up to get in between the joists, 45 degrees to even it out and use the existing hole. I know the run will be about 10-15 feet at that point and about three turns. Will that be okay?? Too many angles to be efficient??

Thanks I really appreciate the help.

md2lgyk · 03-05-2012, 09:28 AM

Just get rid of the radon pipe. Radon mitigation is nothing but a scam.

rjniles · 03-05-2012, 02:18 PM

The rim joist is sitting on a mud sill which is on the concrete foundation wall. There should be no problem cutting a 4" hole in the rim. It is not spanning anything and has plenty of support.

john620 · 03-05-2012, 02:24 PM

Even that close to the radon pipe hole? Which is about 4"x6" and through the top of the rim joist. Or should I move over a joist and make a hole in the rim joist there? Of course that adds length and angles to the vent.

joecaption · 03-07-2012, 11:27 PM

I agree, no not with the dumm as* with the escort company that keeps trolling.
Get rid of the flex pipe and go with hard galvinized pipe or 3" PVC and go through the rim joist.
Totaly differnant then what you may have been reading. What you may have seen is holes in a floor joist.

john620 · 03-08-2012, 07:49 AM

Sorry joecaption I don't understand your response at all. "dumm as* with the escort company that keeps trolling", not sure what you are talking about.

PVC is an absolute no, no and at 3" that is too small anyhow. I agree I should go through the rim joist but my question is where? There is already a large hole where the radon pipe is and I don't want the pipe to be 15 feet long either (running it between other floor joists).

Any help??

DexterII · 03-08-2012, 08:11 AM

You're there, and I'm not, but are you sure that the radon pipe goes through the joist? If I'm looking at the picture right, it looks to be like it goes vertical before reaching the joist. Regardless, if the radon pipe does go through the joist, I would typically jump over one bay, if for no other reason than for future maintenance. Doing so should be no problem with a pair of adjustable metal elbows. Use metal rigid pipe, metallic tape, not regular duct tape, and no screws; everything you need is available at your lcoal hardware or big box.

john620 · 03-08-2012, 04:01 PM

Here are two pics up-close of the radon pipe in the rim joist. When I first saw it I also thought it went vertical before the joist but unfortunately that is not the case (though if it had this project would be much more simple). The pipe went too far back to the rim joist so the builder cut a block out of the rim joist and then bent it up into the wall.

DexterII, I agree I should go over a joist bay. It will add some turns to the venting pipe but seems worth it.