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How Can I Stop Secondhand Smoke From Getting Into My Apartment?

Close up photo of a lit cigarette with secondhand smoke

You may find yourself asking “if no one in my household smokes, why can I smell secondhand smoke inside my apartment?”. The CDC has determined that there is no safe level of secondhand smoke, and over 2 million nonsmokers have died in the US since 1964 from health problems related to secondhand smoke1. The best way to avoid secondhand smoke is to keep your home smoke free, but what do you do when your neighbor smokes like a chimney? There are a few different ways that odors from secondhand smoke, technically called environmental tobacco smoke (ETS), can enter into a neighboring unit. Finding out what is specifically happening in your situation may be a bit of a challenge.

Pathways for Secondhand Smoke

When we do inspections for this kind of concern, we always check for the most common pathways first. The most common pathways are wall openings along a shared wall. This could be an electrical outlet, light switch, plumbing opening under sinks or for laundry hook-ups, or any other opening in the wall. Another common issue may come from shared exhaust ductwork. Ideally, there is a damper that closes when the exhaust is not in use to prevent any air infiltrating from the connected spaces, but this is not always the case. Occasionally there may even be a gap where the wall and flooring meet which allows for air to move from one unit to another very easily.

Building Pressure

Openings in walls are only part of the story. An equally as important issue to understand how secondhand smoke can enter a neighboring unit is pressurization. In buildings, pressurization is a major factor in how air moves from one space to another. Without getting too into the weeds, it is important to know that air will move from an area of high pressure into an area of low pressure. Some things that can create a negative pressure in a space are bathroom/kitchen exhaust fans, a clothes dryer, or a furnace. There are some building dynamics which will affect pressurization such as stack effect. This is the movement from the air in lower levels to higher levels. Therefore, if the smoker is in the unit below you, the secondhand smoke will usually move up into your unit easier than it could move down into a lower unit.


Sealing up physical pathways into your unit can be done for example using spray foam. Having a smaller opening, or possibly sealing off openings completely can significantly reduce the amount of secondhand smoke entering into a neighboring unit. Addressing pressurization in a building can be more difficult. Increasing pressure in your unit could be done by adding an outdoor air intake to the HVAC system. In a rental, this would require having a very cooperative landlord!

Of course, these are only a few examples of situations we can see related to secondhand smoke. In fact, these issues can be some of the most complex issues we work on as indoor environmental professionals. Each year fewer and fewer people in the US smoke, so hopefully in the future, we will see less conflict over this issue.

  1. U.S. Department of Health and Human Services. The Health Consequences of Smoking—50 Years of Progress: A Report of the Surgeon General. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014

Ian Cull

Ian Cull is a nationally recognized expert in the field of indoor air quality. He is the Chief Science Officer of Indoor Science, a company he started in 2004. He speaks around the world on air quality topics and is a training provider of the Indoor Air Quality Association. Mr. Cull is a Licensed Professional Engineer (PE) and Certified Industrial Hygienist (CIH). His degree is in Environmental Engineering from the University of Illinois - Urbana Champaign. Mr. Cull has developed 50 air quality related courses for the IAQA University and is the author of the book, “Fundamentals of Mold Remediation”. In his words… “Besides being passionate about indoor air quality, I enjoy cycling, music, the Chicago Bulls, and having fun with my three kids.”

10 thoughts on “How Can I Stop Secondhand Smoke From Getting Into My Apartment?

    I’m having problems with the downstairs neighbor. His smoke is coming from the baseboards (heating vents) I live on the second floor apartment. There are only 2units in the building. His and mine. How do I block the smoke?


    Stopping second-hand smoke from entering a neighboring unit can be very difficult. Air naturally moves from lower levels to higher levels due to stack effect, so it is going to be an uphill battle. Some things that might help (but I can not guarantee will stop the smoke) would be to close up any openings into wall cavities such as around plumbing. Some people have had relief by caulking around baseboards and electrical outlets, and some people have even gone as far as placing baby safety plugs in electrical outlets they are not using. If you are friendly with your neighbor, you could ask that they keep a bathroom exhaust fan running, this can slow the air movement into your unit by lowering the pressure inside of their unit.

    I found your article very informative. Just what I was looking for. However, I am looking for a little more information regarding solutions. I live in a HUD facility in NH. it is an indoor six-story complex with elevators. It’s a smoke free facility. The only smoking allowed is at the edge of the property in a little smoke shack. The problem is, it’s getting cold outside (32 degrees) and my neighbors are smoking in their apartments. The neighbor directly below me is smoking so much, it’s kicking off my asthma and my migraines. I’m getting physically sick. I’ve been documenting the times and giving it to the Property Manager but it is still happening every single day.

    They’ve gone to their door and asked them if they are smoking. Of course they said no it must be coming from the apartment below them. but the smell and the smoke is too strong to come from anywhere but them. I live on the corner apartment. I have nobody adjacent to me. Only them below me. Management said there’s nothing they can do. Because the law requires them 24 hours in advance to be able to enter their apartment. I’ve written a note asking them not to smoke, but they’re still smoking.

    is there anything that I could get that could detect SHS to prove I’m being sickened by this?


    This is a common issue that we deal with pretty frequently. There are tests available to test for second-hand smoke, but we have seen that even with this data, it can be hard to convince management to take the issue seriously. The tests only say if the tobacco smoke is present or not, it doesn’t say from where it is coming from so using it to prove that a specific person is smoking is difficult.

    I live in a condo that I own for many years and recently have had smoke Infiltrating my unit. I’ve always been a very healthy person with no asthma or allergies but note I’m becoming seriously ill from smokers. So I’ve taken a proactive part in resolving this issue. I’ve contacted everyone from my property manager to Tobacco Free Florida (was given a list of smoke free multi-housing communities – these are places that ban smoking within the entire building including all units). Ironically the smokers have more rights we have to find ways to prevent their toxic smoke from invading our personal space; should really be the other way around. The onus should be on them to ensure there smoke doesn’t encroach on others. They should have to find housing that is just for smokers only just like there are smoke shops or smoke lounges. By the way many of these places have special HVAC systems designed to remove smoke (air scrubber) but even with that you walk by them you can still smell a waft of smoke. Also contact your Govenor’s office because with the current concern over COVID-19 and CDC claiming the dangers of secondhand and third hand smoke from all forms of smoke ie cigarettes, cigars, vaping, e-cigs, marijuana there’s been so many complaints so legislators are going to address it but people need to contact their government officials to make formal complaints. What I don’t get is that there’s been so much evidence of the dangers of secondhand/third hand smoke that Mayo and Cleveland clinic claims nothing can filter out the toxins and the only way to prevent becoming ill is to get away from it. So then why was it banned in restaurants and workplaces but hasn’t it been banned especially in condos, apts. I have someone coming to test areas/cracks/conduits of possible smoke entry to have them seals up because I want to sell my place and move but don’t want to pass my problem on to someone else.

    Hi, our building is smoke free…
    Our new neighbors are in their 20s…with 3 small children(one is a baby.they smoke pot, cigarettes, and it smells like vapping(cherry ) to cover the stence. We have seen them smoke, we can smell it, they smell of pot, their vehicle,etc..
    We disrespect they might dispense. ,but I’m going off topuc. They deny, but we all cough, sneeze,and end up wheezing.I wake up in middle of night if they smoke.
    There are 4 tenants in this building over 70, all have serious issues, asthma, copd, allergies, cancer….then there’s 3 of us in our 60s, with issues, and a couple of us in 50s..the rest of the tenants are college students.
    The city has us fill out one complaint form, one person, every 6 months? Ok, where are our rights and why do we have to prove they smoke? When it’s obvious?

    If it’s a smoke-free apt you have rights that can be enforced. Contact your management office. You’ve paid to live in a smoke free environment. Also contact Tobacco Free office in Denver which is part of the health department. I would recommend contacting your Govenor as well. This is serious stuff.

    I live in Denver and am trying to prove my neighbor is smoking. The manager is protecting the smoking neighbor. I am doing the home air check but want to find an Air Quality Monitor for Nicotine and PM 2.5. Do you have any suggestions?


    I am not aware of a monitor for nicotine. Nicotine is typically found deposited on surfaces, not as a gas in the air so most tests for nicotine are a wipe sample. I will say that in our experience it is very unlikely to recover nicotine in your unit when the smoke is coming from a neighboring one. Nicotine does not pass through walls well compared to other compounds. There are a number of consumer monitors which measure PM2.5, but I have not had experience with these devices to recommend a specific model.

    Hi Dylan! Our downstairs neighbor smokes non-stop and the smoke is getting into our unit. Do you know anyone in the DC/VA area that could inspect our home and recommend solutions? Thank you!