Townhouse exhaust vents too close — neighbor’s cooking smells coming into my basement/kitchen

Hey all,

Looking for some advice here.

I live in a townhouse in Ontario and our kitchen range hood exhaust vents are on the exterior wall, but they’re really close together (basically side by side between two units).

Whenever my neighbor cooks (especially strong stuff), the smell gets blown straight toward my side and somehow ends up coming into my place. I’m guessing it’s either getting pulled back into my vent or just sitting in that small space between the fence and wall.

I’ve attached a photo for reference.

Some background:

A while back I made a post here about how there’s a corridor between the townhomes that seems to trap smells, and those smells eventually seep into my basement and kitchen.

Old post:

Since then, the builder actually came by and checked things out:

- They fixed the dryer exhaust and piping and re-taped it

- That issue is now resolved (dryer smell is gone 👍)

However:

- The basement still gets a lot of cooking smells

- Builder basically said they can’t do anything further

But I’m still not convinced that’s the end of it.

Now that I’ve taken a closer look, I think one of the main culprits is this exterior range exhaust setup (in the photo), and possibly how it interacts with airflow around the house.

I also have a feeling there could be something HVAC-related (like negative pressure, air being pulled in, etc.), but not 100% sure.

What I’m trying to figure out:

- Would a better vent cover (hooded/angled) help redirect airflow?

- Do backdraft dampers actually stop this kind of issue?

- Is extending the vent outward something people do in these cases?

- Could this be partly an HVAC / pressure imbalance issue pulling smells inside?

- Or is this just a design flaw that needs a bigger fix?

- Also—if I were to try a DIY fix first, what should I actually be asking for at Home Depot / Rona?

Not trying to cause issues with the neighbor—just want a practical, safe, and ideally code-compliant fix that actually works.

Appreciate any insight or experiences 🙏