Party wall poor sound insulation & smells coming through

[webbit]

Hi all,

New to the forum so Hi and thanks in advance for any advice! Hopefully I've posted in the right place.

I've got a 1930's property with a 9in red brick party wall. I had expected the soundproofing to be pretty good however I can hear my neighbours clearly and have strong cigarette & cooking smells seeping through.

As smells are getting through I think that's probably why the sound proofing is so bad, I've managed to spot where it's coming from - upstairs between the skirting and the floor in all rooms linked to the party wall. Downstairs the only area I have spotted is from a gap above the door frame of an under stairs cupboard (stairs run adjacent to party wall).

Has anyone ever heard of this before, party walls aren't supposed to have air gaps are they? Plaster work on the walls looks solid and flooring is level with no unusual creaking etc (I lived in a house with subsidence before with flooring problems!).

If I was to pull up floor boards and spray expending foam between the joists to seal the gaps would that work - is there anything more suitable I could do?

Many thanks,
Webbit

 

[Deluks]

Sounds like the joists sit in shared holes in the party wall. Foam will help with the smells but not so much the noise. Best bet is to fill the holes with mortar and cut up bits of brick. Slightly disruptive but worth it in the long run.

 

[ajrobb]

Do the floorboards run along the party wall rather than at right angles to it?

 

[webbit]

the floorboards run at right angles to the party wall.

In the loft the main joists run front to back of house/parallel with the party wall.

Thanks

 

[ajrobb]

If the floorboards are at right-angles to the party wall, it doesn't sound like the joists go through the party wall but rather run front-to-back like in the loft. Maybe the party wall is porous. Have a look at Soundcoat Plus; it is intended for sealing walls, including party walls. I'm not sure it will do you much good though as there is probably a joist running close to the wall blocking access to the bricks. You could try taking off the skirting board and using soundcoat between the joist and the bottom of the plaster then an acoustic foam sealant down the side of the joist between the top of the joist and the soundcoat.

 

[Deluks]

Maybe the party wall is porous.

1 brick thick wall?

Gotta be holes in the wall somewhere, either the neighbours joists go into the wall or there are some missing bricks/holes from previous work.

 

[webbit]

Thanks for the advice. I haven't had a chance to lift the floorboards upstarits, however did manage to poke my head through a gap in the kitchen cupboard. Looks like a mis-match of bricks and breeze block? I only had limited access and could only see where the plasterwork had cracked off though.

 

[hancock]

Id say take all skirtings off & dry-line wall with 1.200x2.400 poly backed plaster board then scim. Fill in holes round joists and put skirtings back when dry. I know a bloke who did this & he said it was fab on noise reduction, also make your house warmer.