We are on septic, and have been having foul odor from washing room. We took the wall down to find that the vent pipe is not vented through the roof, and does not have a cap. Help what should we do?

Hey Jbass...

You can run the vent up through the roof and stub it up between 12-18" above the roof, OR install a mechanical vent (called an AAV... air admittance valve)... see image.

These pro vents (just another name for them... ;)) are threaded and need to have pipe dope or teflon tape put around the threads and get spun into a 1.5" or 2" female threaded PVC fitting and then primed/cemented onto the PVC pipe.

If your pipe is not PVC then you will need to get an appropriate shielded transition clamp (see image) to transition from your pipe to the PVC female adapter mentioned above.

These mechanical vents must remain accessible at all times as they can fail so you will want to install an access panel (see image... can be painted) for future replacement if needed.

All of this is available at most home improvement stores.

Let me know if you need more info...

MARK

Another option would be to revent back into a existing roof vent in the attic. This is done using a inverted sanitary tee off the existing roof vent. We do this all the time in upscale single family residencies where they only want a single main vent to exit the roof and then we had to bring it out on the back side. Regards, tom