These guys will be repelled by the chemicals and retreat from going in your attic.
Dust attic for flies.
Fly lights plug into standard outlets and can be placed in attics basements and rooms that are not often used like guest bedrooms.
Use a fly light.
Do not apply too much dust at once or the dust will not be effective as cluster flies will avoid piles of dust.
Inject diazinon or bendiocarb dust into window pulley openings and wherever possible into wall voids and other confined spaces where the flies may be hibernating.
To kill the flies that buzz about rooms use a synergized pyrethrins spray or aerosol.
Place dust in cracks and crevices.
A diazinon spray or dust may also be used for longer residual action.
Then once the relentless heat zaps the pesticides strength life goes right back to normal for the pest no worse for the wear.
Place protective screens in attic and chimney openings.
Attic flies which are also known as cluster flies are insects that often migrate into homes in the fall where they hibernate for the cooler fall and winter months one of the best tips for getting rid of attic flies is to keep them from entering the house in the first place as trying to eliminate them after they are in hibernation can be difficult.
Identify where they are.
To be for sure successful attic treatments are still a challenge for pro or diy alike even with some of the best equipment.
Seal up all cracks and crevice and any holes.
Spray insecticide where cluster flies hibernating.
Remember attic flies want to cluster indoors when it starts to get a lot cooler outdoors.
Spray as best you can around your roof chimney eves ventilation holes etc.
No fog dust or spray in the world will get to anything there.
1 2 puffs at a time will be plenty.