Will an air purifier alone stop the weed smell coming through my vents?

It helps, but it won't fully solve it on its own. A HEPA-plus-activated-carbon purifier captures what's already floating in your air, and you want one running near the worst vent. But if smoke keeps pushing in through unsealed gaps, the purifier is constantly fighting the source. Sealing the entry points first is what makes the purifier actually keep up.

Can you remove the smell permanently if my neighbor keeps smoking?

We can permanently seal the paths the smoke uses to get into your unit and fully clear the odor that's already soaked into your walls, ducts, and contents, with our 100 percent guarantee on the work we do. What we can't control is your neighbor. As long as they smoke, sealing plus a carbon air purifier is what keeps your place clear. The vast majority of what bothers people comes through fixable gaps, so the difference is usually night and day.

Do you use ozone in my apartment to get rid of the smell?

No. We don't use ozone, and we don't use chlorine gas. Ozone is a toxic gas that's only ever considered safe in a fully empty space, and it can damage electronics and rubber, so we leave it out of our process entirely. Instead we use green, non-toxic methods: source removal and cleaning, enzymatic and oxidizing treatments, thermal fogging, a hydroxyl generator that's safe to run while you're home, HEPA and activated-carbon scrubbing, and sealing. We'll tell you straight which combination fits your situation.

Weed Smoke Smell Coming Through the Vents From a Neighbor: How to Stop It

Cannabis · By Odor Removal Experts · Updated June 2026 · Cleveland and Northeast Ohio

If you've got weed smell coming through vents from a neighbor apartment, you're dealing with two separate problems: the air pushing in, and the odor that's already soaked into your place. Most folks try to mask it and wonder why it's back by morning. We've run these calls all over Greater Cleveland and Northeast Ohio, and the fix is almost always about airflow first, then treating what's left behind with green, non-toxic methods. Let me walk you through what actually works and what's a waste of money.

Cannabis smoke is stubborn because it's loaded with sticky, oily compounds and tar that cling to drywall, upholstery, and the inside of your ductwork. That's why a spray-and-pray approach fails. You have to stop the migration and break down the residue, not cover it. We never just mask the smell, and we never use ozone or chlorine to do it.

The short answer

Neighbor smoke rides pressure differences through vents, outlet gaps, baseboards, and shared wall cavities, not just the grille. Stop it by pressurizing your apartment with a window fan blowing out and sealing those leaks, then run a HEPA-plus-carbon purifier. Sealing the entry paths is the real fix; a pro finds the actual gaps, seals them, and treats the odor already soaked into your unit.

Smoke sneaks in through gaps around vents, outlets, and baseboards, not just the grille.
Pressurize your apartment so air pushes out instead of pulling smoke in.
Seal the entry paths first, then run a HEPA-plus-carbon purifier.
A pro seals the paths and treats odor already in your walls and ducts.

Why neighbor smoking weed smell gets in through your vents

Apartments share more air than people realize. Smoke from next door rides what's called the stack effect: warm air rises through the building, and pressure differences pull it through any gap it can find. The vents are the obvious suspect, but they're often not the main one.

On most jobs we find the smoke isn't actually coming through the supply or return grille. It's sneaking in through gaps you would not think to check:

The duct boot where the vent meets the wall
Behind outlets and switch plates on shared walls
Under the baseboards
Around recessed lights
The cavity where plumbing or cable passes between units

The vent just gets the blame because that's where you smell it strongest.

If you live in an older Cleveland multi-family or a prewar Northeast Ohio co-op, the shared chases between units are usually the highway. Newer buildings with central HVAC can recirculate one unit's air into another if the system is balanced wrong, but that's less common than people think.

What you can do yourself tonight

Before you call anyone, there's real DIY here that helps and costs almost nothing. Pressurize your apartment so air pushes out instead of pulling in. Crack a window and run a window fan blowing outward, or run your bathroom exhaust fan. Positive pressure means your neighbor's smoke has a harder time getting in.

Then plug the leaks you can reach. This is the part that actually moves the needle:

Seal around outlet and switch covers on shared walls with foam gaskets (a couple dollars at any hardware store).
Run a bead of removable caulk or use weatherstripping where baseboards meet the floor on the wall you share.
Tape off the vent temporarily with painter's tape and plastic if it's a non-essential return, and see if the smell drops. That's a quick diagnostic, not a permanent fix.
Put a quality activated-carbon filter in front of the offending vent or run a standalone HEPA-plus-carbon air purifier. HEPA alone won't touch odor; you need the carbon to grab the gas-phase compounds.
Wipe down hard surfaces. Smoke residue on walls and glass keeps off-gassing for weeks.

How we block cannabis smoke from next door for good

When the DIY gets you 70 percent there and you want it gone, that's where we come in. Everything we do is green and non-toxic, safe for kids, pets, and electronics, and we work in a clear order, because skipping steps is why home remedies stall out.

Find the actual entry points. We don't guess. We look at pressure, check the duct boots, pull a few outlet covers, and trace where the air is moving, because treating the air without sealing the path just lets the smell come back the next time the neighbor lights up.
Seal the paths. Proper duct boot sealing, gasketing penetrations, and air-sealing the shared-wall gaps with the right materials, not a tube of caulk smeared around, is the step that permanently changes how much gets in.
Treat the odor already in your unit. We start with source removal and cleaning, then enzymatic and oxidizing treatments that break the residue down at the molecular level instead of covering it, and HEPA plus activated-carbon scrubbing to pull the airborne load out.
Handle heavy saturation and seal what off-gasses. If the smoke has gotten into soft contents and the place is heavily saturated, we run a hydroxyl generator that's safe while you're home, or use thermal fogging to chase the odor into the same pores the smoke used, then seal any surface that keeps off-gassing so it stays put.

Why we don't use ozone for this, and what we use instead

You'll see ozone pushed hard online as the magic bullet for smoke. We don't use it, and we don't use chlorine gas either, because the risk isn't worth it when there are safer ways to get the same result, so we built our whole process around green, non-toxic methods.

We don't use ozone, and neither should you at home

Ozone is a toxic gas that's only ever considered safe in a fully unoccupied space, because it's hard on your lungs and can damage rubber, certain plastics, and electronics in the room. Anyone telling you to sleep in a room with an ozone machine running is giving you bad advice.

For an occupied apartment where you can't leave, the hydroxyl generator does the heavy lifting on airborne odor and it's safe to breathe around, so we can run it for hours while you go about your day. Pair that with enzymatic and oxidizing treatments on the residue, HEPA and activated-carbon scrubbing, thermal fogging, and sealing, and you get the odor handled without anyone having to clear out or worry about toxic gas.

A realistic note on results and your neighbor

Here's the honest part. We can stop the migration into your unit and clear the odor that's already there, usually with the smell gone in 1 to 4 hours of active treatment, same-day or next-day in Cleveland and Northeast Ohio. What we can't do is stop your neighbor from smoking. As long as they keep at it, the value of the sealing work is what keeps it out long term, and the air purifier handles the trickle that any shared building lets through.

If you rent, loop in your landlord or property manager before you start. Sealing penetrations and duct work can touch building systems, and a good manager would rather pay to fix the path than field complaints every month. We work with plenty of property managers and do this discreetly with fully insured techs.