I am very confused by your post. Exterior waterproofing (spray damproofing or membrane waterproofing?) on an existing basement would be covered up by grade outside. Even if it is off-gassing, how is that smell getting inside and how would a dryer vent discharging above grade, or a kitchen upstairs have anything to do with that? What does the waste&vent plumbing system have anything to do with a stormwater system for a basement - they should remain independent? And sewer smells are prevented by Ptraps at each fixture location, not a backflow preventer (which prevents sewage from backing upwards from the street into the house)?

Did you happen to instead have an interior drainage system installed where they cut around the basement perimeter slab, install piping, a sump pit, and wall membrane?

Thank you for the response. It was only an exterior waterproofing (walls coated with mastic and plastic). We have been unable to determine how the smell is entering the basement. The waterproofing company believed that it might be through the plumbing as the floor drains in the basement did have a stronger smell. With the drains blocked, the smell continued. Both plumbers have stated that there is nothing they can do to help with the smell.

The dryer comes in to play as the seems to magnify the smell and saturate the clothing in the dryer with the smell. The discharge from the dryer is not the source, but the air in the basement. I am unsure why the stove is also magnifying the smell.

We are at a loss to determine how the smell (off gassing) is getting into the basement.

Houses have a natural suction commonly called 'chimney effect.' Sun shines, heat rises, there are leaks in the house that let hot air escape, and there is a very slight vacuum inside the house on the lower levels to replace the air that has left. What you are experiencing is vapor intrusion which results from this process.

If you are using a vent fan in the kitchen or bathroom, anywhere in the house, it will increase the suction. Crack open a window or door on the same floor whenever you are using a fan so the air is replaced directly from outside (which I hope does not smell). The dryer is also blowing air outside of the house so it's creating suction as well.

How did you use charcoal? If you had a flow-through activated carbon filter I would think it should help this problem by absorbing hydrocarbons. Just leaving a tray of charcoal out will not be enough to handle the volume.

Are you keeping the basement sealed off? This should help reduce the odor into the rest of the house and also reduce the pressure differential that is pulling the vapors in. You might consider really sealing up doors from the basement to the rest of the house with a rag or towel stuffed into the gap.

Are there any windows at all in the basement that you can open? I think you would have if there were.

What kind of 'air purifier' did you try? An ionic type, one with some kind of filter, ? How much air does it move and what size area is it supposed to handle?

An ozone generator might do the trick but you wouldn't want to run it all the time. Ozone is pretty bad for humans.

If you are in a climate that is not super cold right now, you might consider using the dryer vent as an exhaust for contaminated air. Since you can't use your dryer anyway, hook up a small fan to the duct. Only problem is you have to have somewhere for air to come into the basement so as not to create more suction on the foundation. That would be either a window or door to the outside, or if there is none, leave the gap under the basement door open so air will be pulled from upstairs, halting the spread of vapors through the house.

It's all about air movement, so you have to think about how air is moving when you open and close doors, turn on fans, etc.

@jason2022 I am dealing with the exact same situation. The -exterior- was waterproofed 8 weeks ago. My entire house smells like kerosine. Absolute nightmare. It is clearly getting in through the fieldstone foundation.

Has your situation been resolved? Please let me know.

@jason2022 and @Greg Pontrelli,

I'm dealing with the exact same situation myself now. My house is a semi detacted.

My neighbour recently (2 weeks) had the back wall of her side of the house waterproofed.

The contractor choose to do the job on a day when it snowed. He told his client my neighbour that normally they use a water based product but since it was colder and snowing he used something else. (Still waitiing to find out exactly what). Every since then my house has smelt like a varsol or kerosene smell. Very strong smell. My attached neighbour is also experiencing this hardcore smell as the waterproofing was applie to her side of the house.

It seems to still be strong 2 weeks after the initial. We tracked the strongest smell to the floor drain at the front of the house. Both sides of the house have the smell coming from the front floor drains. We have plugged the drains with foam/plastic, but it still somehow gets into the living space.

When you walk in from outside it's very noticeable and strong. If you stay inside you get used to the smell. My wife and also the neighbours daughter are both sick for the last week suffering from sinus infection and headaches as well as a cough.

Did either of you ever come to a solution for this issue now that it's been a year since you had this problem.

Im really sorry to hear you are experiencing this.

Our problem persisted strongly for months and it was dreadful.

In the short-term, the company that applied the outside waterproofing brought in ”negative pressure fans” which essentially sucked the air out of the basement and pushed it out the windows. this brought the horrible smell from a 10/10 to a 6/10.

They even dug out the dirt to expose the tar application to air and warm sun. they did this for a month and the smell persisted.

Ultimately after months, the smell never went away. So we told the company they had to remove the product from the foundation. The spent a week or more with hammers and chisels removing the tar. (we have an old fieldstone foundation. but if you have cinderblock or brick, its possible you could pressure wash it)

Once the application was remove- the smell stopped.

We then had an organic product applied- called Safecoat DynoSeal. It had no smell.

During the process I spoke with contractors, the product suppliers and distributors, and other home owners.

My assessment is that these applications are only right for certain homes and situations, that the product quality varies greatly (and so does its ability to cure), and even in a perfect world, I dont believe these applications are ever suggested to be applied in cold temperatures.

Hi Jason2022, How long in total would you say it took for the smell to subside? Going through the exact same situation.

Hi! just wondering, to those who had this experience, how long did it take for the smell to subside? we recently had this done (its november in canada so its cold- worried the curing will take too long). removing the product doesnt seem feesible as it was a long expensive project. the house doesnt smell too awful but its very obvious when we use the basement dryer and oddly our oven on the main floor.

Winderinf if anyone has an update on how long the smell took to dissapate. one side if our home was damp proofed without our permission and we’ve been forced to live elsewhere because of the smell.

Jet Black AE was applied in very cold weather (december in toronto, -10C) and the house still smells over 4 months later.

We are going through the same exact issue. we cannot use our dryer in basement and oven on main floor is affected. It has been 3 months since exterior waterproofing and we have not been able to use our dryer at all. Can anyone share what worked for them or how long it took for the smell to go away and gas appliances to be able to be used again?