The rule here is simple.
Difference between attic and scuttle.
You can buy some poison to kill the squirrels or rats in a garden centre don t let them stay up there as they can do lots of damage to the wiring etc if they remain.
Probably a bird or squirrels.
To make sure that it isn t just a gaping obvious hole in a ceiling it often has a removable.
If ductwork is located in the attic make sure to insulate it as well to reduce heat loss and gain while passing through this unfinished space.
This means you should insulate between and over the floor joists.
The goal with an unfinished attic is to seal it off from the main living space below.
Check this out for more info.
The difference is pressure is most commonly created by a difference in temperature.
The bird will die after a few days if it can t get out.
A scuttle attic is an attic space accessed only by a small hole in a ceiling or less commonly a wall.