On Tue, 06 Mar 2012 12:08:41 -0500, Steven Bornfeld
wrote:

I write in hope of some serious answers. I know this general issue has
come up before, and wading through the incredulous and the trolls doing
a search yields nothing that seems likely to work. Maybe there is
nothing; if not, so be it.
We just moved into our new home after over 7 months of renovations. The
problem is cigarette smoke from one of our neighbors.
This is an attached house, with a party wall (concrete). (attached on
the other side too, separate construction, not a problem.
When the walls were open, I was not aware of any plumbing coming
directly from the smoking neighbor. There are cabinets mounted in our
kitchen on the party wall. Holes were cut in the cabinet backs to
accommodate some drainage and steam pipes (ours), and there is an
opening around our plumbing which we will seal off. We don't know what
might be the best way to do this, and I have no idea if it will work
(though the cigarette smoke is strongest in these cabinets.
This does appear to be coming through the walls--somehow, and not
through vents to the outside. This is old construction (c. 1940).
There is no question that there is cigarette smoke. It's not nearly as
big a problem for me (my sense of smell was never the same since organic
chemistry), but my wife is very upset.
I'm quite sure I have no legal recourse, and in any case wouldn't expect
my neighbor to modify his smoking on my behalf. Really just interested
to know if anyone has dealt with some mechanical means of dealing with
this problem that was effective.

TIA,
Steve

Since you can't smell it, I'd try to confirm there is actually a
smell. You wife's smell might be off.
If she's a rabid anti-smoker, just seeing somebody smoking downwind
and 100 yards away can cause her to smell cigarette smoke,
You got good advice except for that omission.
I'd go for positive pressure first.
If that doesn't do it, the smell is old stuff that hasn't been sealed.
Or in her olfactory imagination.

--Vic