| I've got the same issue, where the neighbor smokes weed and it's so bad it's seeping into my house. |
| Someone dug up a roach of a thread! we're not in covid isolation anymore. |
| Air gaps in the masonry where mortar has eroded away over the years and then seeps out around the wood work. Very common in DC row houses. Will be MUCH worse if you have any exposed brick and if they have any exposed brick. |