Toilets, Sinks, Showers, Tubs and Disposals - horizontal venting?

I found a 2 1/4 PVC pipe coming out of the house exterior wall about 2 feet above ground. Is this a vent or air return or something? Due to critter concern I capped it but have started getting odor in shower. Haven't checked the roof vents yet so don't know if this is coincidence or what this pipe is for.

You shouldn't cap it if you don't know what it is. What kind of critter are you worried about? In my area. I have never seen a plumbing vent like this, but you never know what the previous owner did. If I had to guess, I would say it's probably the source for combustion air for the furnace or waterheater.

You should probably rethink capping off an unknown pipe, whats better a "possible" critter problem or potential sewer gas or carbon monoxide poisoning in your house?

good luck

I know someone who has a PVC pipe coming from the side of their house for a furnace. The size would be 2". They have an elbow attached to the pipe and a vent cap. There is a commercial website www.ecaproof.com that has a picture of one coming out of the sidewall of the house. The cap cannot be purchased from this website to the public, however, there is a site called www.pvc-cap.com where it can be purchased by the public. It can also be used for your roof vent pipes. It protects as it vents. Just whatever you do, do not cap the pipe off. It needs to vent.