My daughter is buying a house that needs some plumbing fixed.
The Sink S traps are not vented in both bathrooms and in the kitchen. What has to be done to vent these traps?

Hello, are you saying that you can see the drainlines exposed outside the walls? Or are they coming out of the walls? If all you can see are the lines coming out of the walls then the vents would normally be concealed in the walls.---Zeke

I'm not sure. The house is in St. Louis, MO and I won't be there until next week. I was just trying to get ahead of the game, by doing some research and get my tools packed. I'll call my daughter tomorrow and ask her to go over there and look to see if she sees drainlines outside the wall. Thank you. I'll be in touch as soon as I get the needed information.

Vents should be inside the walls, therefore, invisible from outside.

Okladad44 - You won't see the vents ,they will be I nside the walls and under the house. You should be able to see a pipe comeing out through the roof. That would be the vent pipe for the plumbing of the whole house, ( SHOULD BE ANYHOW) Fill the sinks with water and see if they drain out real good, if it does then it is vented . Good luck and GOD BLESS ::: F.B.E.

My daughter is buying a house that needs some plumbing fixed.
The Sink S traps are not vented in both bathrooms and in the kitchen. What has to be done to vent these traps?
The easiest way to vent those traps would be to install a "P" trap with a AAV,(Air Addmitence Valve),(see image) before dropping down to connectto the drain. Good luck, Tom