Again, your vet will give you a spray for your home. I would never use anything without a vets approval.
When i first got Rosie she had a flea, so frontline was applied to her, and the vet gave us a spray for along the edge of the floorboards. We had to spray upstairs first and open all the windows and close all the doors, then when we went to bed all of the downstairs was done in the same manner.
The fumes are toxic so that's why it has to be done that way.