Party walls, explained
Why the wall between two houses is a hallway for mice
Row homes in Philadelphia share their side walls, and often a shared cornice, chimney stack and cellar line. A mouse that gets into one house can walk the length of the block inside the walls, past every cut for a pipe or wire.
That is why treating one house rarely settles it. Closing the openings on your side is the start. What happens on the other side decides how long it lasts.
What we've learned about attached houses
Mice travel along pipes, wires and joists
Each opening is a way in and a way across
The cellar and the cornice are the two big routes
A vacant house next door is a common source
Your side
Signs that the wall is the way in
You can notice these before we ever come.
Scratching in the wall at night
Usually near a chimney breast, a pipe chase or the kitchen wall you share.
The same noises in both houses
If your neighbor hears it too, the openings are probably along the wall you share.
Gaps around pipes under the sink
A ring of space around a pipe is a doorway.
A sealed hole that opens again
A new opening beside an old one often means the route is the wall, not the hole.
Droppings in a cellar corner
Look where the cellar wall meets a neighbor's wall.
A smell that comes and goes
It can come from inside the wall and from either house.
Different houses, different walls
What changes with the house you live in
You're in the middle of a row
Two party walls, so two neighbors. We start with the one where you hear the noise and ask you which neighbor you know better.
You're at the end of the row
One party wall and one outside wall. The end house has more cellar windows and vents, so the outside matters as much as the wall.
You share a twin or duplex
One wall, one neighbor, and often one cellar line. The conversation is shorter and the sealing can be done on the same day.
Next door is empty
We can't go in, and we can't tell you who owns it. We note on your scope which openings face the empty house and what to watch.
Your neighbor is a tenant
Tell us who the landlord is, if you know, and we'll write the note to the owner. We don't go into a unit without the owner's say-so.
A note for next door
What we put in the note
You can use this one as written, or ask us to write it for you.
It is one page. We leave out product names, blame and prices.
Hello. We live next door, and we've had mice in the walls we share with you. A pest technician found openings along the wall, and some of them may open on your side too. Sealing both sides at once works better than sealing one. If you'd like to talk it over, or have them look at your side, here's the number to call.
A note is not a request that they hire us. They can call anyone they like.
Not sure which wall it is?
Tell us which house is yours and what you're hearing. We'll say where we'd look first.