You need more than a home remedy.  Big black ants are almost always
Carpenter Ants or termites.  They will eat your house out from under you.
You need a licensed exterminator.  Raid and bombs will not kill Capenter
ants or termites.
 
We had Carpenter ants last year, and had an exterminator in for them.
They had us move the ferrets upstairs (they did not have to treat the top
floor), and they used an odor-free, fume-free spray that was sprayed behind
the dishwasher and under the kitchen sink (they were entering through the
pipe holes), and all along the outside foundation.  It was a "needle
application", meaning that very precise areas were treated.  I have asthma
and did not have to leave the room, let alone the house.
 
They told us to wait an hour and then the spray would have dried and it
would be perfectly safe to bring the ferrets back down.
 
Just be sure to make the exterminators ware that you have ferrets before
they come so they can plan appropriately.
 
Anne
[Posted in FML issue 3031]