Neighbours are chain smokers

[Hazbot]

Looking for advice on how to tackle a concern with neighbours.
An older family has very recently moved in next door to my sister's house and are all heavy smokers.
Almost instantly, you can smell cigarette smoke in my sister's house in the rooms that are joined to the neighbours house, even though there are no windows open or anything.
I didn't really believe her until I went round and could smell it as well.
We know we can't expect them to not smoke in their house (although one would wonder why tenants should be allowed to smoke in social housing) but it's so bad that it's like someone is smoking in my sister's house.
Is there anything we can do to limit the smell? Or tips on how to approach them. She has already bought reed diffusers and plug ins but it's still quite smelly!

Had this in a house I rented a number of years back except they were all avid marajuana consumers. The smell of weed, especially in the summer was just horrendous. I’m sure I was high most of the time. My solution was moving out after ten months as it was a rental and we found something else. Are you a an owner occupier or renter?

I don’t think there is much you can do. Council aren’t going to do anything and as you say, they can smoke in their own house if they want. I imagine the fumes are getting in through air bricks, around windowsills and so on - small and largely unnoticed little gaps. You could try diffusers or similar but that will get expensive doing a whole house, and may not help much anyway. Could try draft excluders around any windows and doors to see if that makes a difference - smoke won’t travel through solid walls. A dehumidifier I don’t think will help much. Can’t imagine they’ll say sure we’ll all just give up our 40 a day habit. If it were me I’d be moving out if in rented. If brought then I guess how much does your sister love where she is? If thinking of selling then don’t get into a dispute with neighbours that could scupper sale, however who’s to say that any new house won’t have worse next door!!

Would something like an air purifier help? It might remove the smell from the air. If you haven't got one could you borrow one and try it out in one room?

The smell is most likely getting in through gaps in the party wall. It won't go through their air bricks, into the atmosphere and then back into your sisters.

Party walls in the loft are often roughly finished and have gaps in the partion.

Check out the loft and see whether the smell is strong there. If it is you need to seal the wall up. Likewise inspect the rest of the party wall.

Your windows closed are probably making it worse because the smell isn't coming from outside, but inside. So having your windows closed is just trapping it inside.

The other possibility is the chimney flue. which maybe is shared. You basically have to sniff out where it smells strongest most quickly after they start. That will give you a clue to where it is getting in.

I had this struggle too. For me, the LR didn't get the smell, it was just in the upstairs bedroom. My house is oldish so floorboards upstairs. I used quite a bit of expanding foam type fillers, to get every gap I could find sealed, then replaced the carpet underlay with a really heavy duty rubber and felt underlay. (I was replacing the carpet anyway, so this wasn't as dramatic a move as it might be otherwise) and those two things did a really good job of stopping the smell getting in. Then those neighbours moved out, so it isn't an issue any more, but I do have lovely underlay!

I'm a chain smoker. I've got one of these (others are available). The flat no longer pongs of smoke when I come in from outdoors and - probably a better indicator for me, the smoker - there are no cooking smells an hour after I've made really garlicky or fried food.

Report it as a nuisance to the Housing Association?

Thank you - she owns the property so sadly isn't planning on moving anytime soon.
She has bought a few air purifiers already and it's a good idea to find out where the gaps are to start filling them. She does keep her windows open and have noticed that they don't open theirs so hopefully it won't get worse in the summer!