Sewer gas smell in office?

[ibeeflower]

Hi,
first time posting...bu I've browsing around. I work in a small office and it's only 2 people with 2 bathrooms. In the early morning 8-9, the office gets this strong smell like sewage. Then after lunch...12:3-3:00 the smell comes back again. Our landlord suggested we pour bleach down our faucets and let the water run for a bit. (Our drains in the bathrooms were sealed closed by the landlords)

Pouring bleach doesn't seem safe to us, so we usually let the water run for 20-30 minutes. We are tired of this method. We are wasting water, and the smell comes back again. My boss has noticed that in her office, the smell is the strongest. She has one vent directly above her head...and the other vents are spread throughout the office. Only her vent/office seems to be emitting this foul odor.

What could it be? The bathrooms don't smell and the city waster dept. already checked everything out.

Any help is greatly appreciated!

Flower

[Terry]

Have you checked to see if there is a floor drain?
If so, you will want to pour some water in the floor drain from time to time to keep the seal in the p-trap.

You can also try cleaning the lav overflow. Most lavs have an opening near the top of the bowl, that lets water run back to the drain below. It can get a bit gooey in there.

[Gary Swart]

Are the sealed drains floor drains? If so, they are likely the problem. The water in P traps in drains seal sewer gas from getting out of the sewer and into the building. The water in P traps that are unused for a period of time will evaporate, and the seal is lost. This is most frequent in floor drains that don't get much use anyway, so they have to be refilled with water periodically. There are devices that could have been plumbed into those drains to keep them filled, but it's a bit difficult to retro fit them. Toilets and sinks usually receive enough use that this is not a problem. I think the bleach idea is not the answer. Running water down drains that already receive frequent use does no good to traps that are sealed.

Terry beat me to the punch! LOL

[bluebinky]

Are you sure it's coming from the drains? It could be "dirty socks syndrome" with the HVAC. Just a thought...

[Gary Swart]

Blue Blinky makes a good point.

[hj]

If bleach did anything, it would just "mask" the problem, not cure it, and if an unused drain needed water, it would only be a couple of glassesful. Do the bathrooms have showers in them? Sometimes the air conditioning installers connect the condensate drain directly to the sewer system, sometimes with its own trap. If so, then during the winter or dry spells there is no condensation to keep the trap full so the blower sucks sewer gas in and sends it throughout the building. It is usually just noticeable, however, where there is poor circulation and the smell accumulates.

[Smooky]

The first thing I would check is to determine if the seal to the toilet is bad. If the toilet wobbles around it may be bad. Also you can sniff around the base of the toilet and determine if the odor is coming from there. You said the landlord had sealed the floor drains, so I would check to see how that was done. Another thing I would look for is a decorative clean-out cover or just an exposed pipe clean-out. Often times the decorative cover is screwed into the pipe. If it is removed there is a tiny hole in the pipe that odor can come out. Also if the cover has been removed and put back on, there may be multiple holes in the pipe. There could also be a bad air admittance valve (AAV) Usually an AAV is near your water using fixtures, in the ceiling, at the top of the wall. The AAV is designed to allow air into the drain system but not let the sewer odor out. They go bad sometimes. If you or another business next to you has a powerful exhaust fan this could explain why the odor is stronger at different times of the day. The exhaust fan causes negative pressure in the building and can pull a lot of odor through a small opening even if the exhaust is in an adjacent space. Another thing I would check is to see if the heat and air system has an outside air intake. Sometimes they can be too close to a sewer vent etc .