Hi I am new to this site but my family is trying to find an answer to our sulfur smell problem in our home. We purchased this home a little over a year ago. Since then we have noticed a sulfur smell that comes from the crawlspace mainly during the months of Mid October to April. During the spring and summer the smell went away. Just today the smell has come back. I have had 2 plumbers come out and both are baffled. They think maybe a low water table. But if we were on a bad water table wouldn't this be occurring year round? The house was built in 1979, we are built into the side of the hill. 3/4 of the home is surrounded by dirt. The front is exposed and the roof is above ground as well. There is a perimeter tile which again if this was broke we should be having a smell all year round. I am 100% positive the smell is coming from the crawlspace. We purchased the home at an estate auction due to the fact the previous owner died in Hospice. I noticed a fan was hard wired into the crawl space and aimed toward the entrance which leads me to believe this has been a recurring issue. There are also 4 layers of plastic that goes the entire length of the crawl space to about 8 inches up the walls. Someone PLEASE HELP us we have no idea how to fix this.
Thanks,
Calebdq

You have to have somebody to crawl into the crawl space to inspect all sewer lines for leaks. There may be a small leak, saturating dirt under it. Also, all ends of all pipes should be properly capped off to prevent sewer gases to enter your crawls space. Sometimes it happens that plumber opens main sewer run, snakes it and won't replace cup with new one.

If there are no leaks, have him to look for wet or high moisture areas in the dirt. That could be associated with ground water.

Question: Are you on septic ?

Back to you...

Milo

Yea I had a plumber come out and checked all the lines underneath the home. I have been under there several times myself. We are on a septic. The odd part about this problem is that it does not occur during the spring or summer. When it starts to get cold out again the smell starts to creep back. The crawlspace is dry. I am no plumber but the thought that it would be the septic or perimeter tile would mean the house would stink year round. I have smelled all the sewage lines to look for a leak but again if this was a leak the smell should be year round. Any ideas why this doesn't occur year round? I have tried monitoring when the smells come to find a common trend. The one somewhat strong comparison is when we draw a lot of water. AKA many showers laundry and dishes at the same time. But the water itself does not smell. It is strictly the crawlspace.Calebdq

During rainy season, ground is saturated with rain water unable to function as well as during non-rainy months. Therefore, sewage discharge hangs on top of the ground or right below the surface, emitting sewer odor. This, together with the Low atmosperic pressure that is associated with rains, is most-likely the cause of the odor.

Hope that helps

Milo

So do you have any suggestions on how to fix this smell? Would pumping the septic help? Or are we SOL with the way the house was built?

Calebdq

You have to investigate to isolate the actual problem first...

Go around your property and see if there are wet spots, soft soil, caving spots, excessive smell in one area, etc. If there is excessive wetness and odor, it may be the case.

Septic itself may not be a problem. It is the combination of composition of your soil and volume of liquid it receives. If that proves to be the case, than I suggest you have a percolation test done first and based on this test proceed with possible leach field upgrade.

Main thing is - you have to get over somebody who knows what (s)he is doing. This person must be capable of pin-pointing the problem and offer solution.

Milo

So is this going to be a plumber or someone else that I would need to contact to investigate?

And I don't know if this will help any but the septic tank is exactly 29 feet 7 inches from the house towards the farmer field and its away from the hill that the house is built into.
Calebdq

I have one last question in regards to this Milo. During last winter the temperatures were well below 32 Degrees Fahrenheit and there was a lot of snow covering the ground. During this time we noticed the largest smell coming from the crawl space. Would this be associated with what you just suggested could be the problem in the soil?Calebdq

I just gave you one scenario. But here may certainly be many others. You may have disconnected vent, sewer slowly dripping onto dirt under the house, deteriorated sewer line below ground level... and many others. Also, since your house is on the hill with septic below, you may have septic using your house sewer pipe as vent, venting under your house.

Smell is coming from somewhere and somebody has to find the source. Usually, Owner will notice only the obvious problems. However, experienced plumber can spot problem with the overall system. As I said, you have to investigate. See if you can get over some old, retired, plumber who has been around the block few times. I am sure he can identify the source of smell in no time.

Milo

Calebdq,
I suggest having your plumbing contractor perform a peppermint test on the dwv piping; this will help determine if the plumbing / piping is a possible source, or contributor to your odor problem. There are companies that can monitor, sample, and, test water, soil, and air for contaminants & toxins...