A.M.
One suggestion that my pest control person gave me is to take the mesh/coiled scrub pads without detergents on it, that you would use on say your grill to clean it, and put those in your weep holes on the outside of your house. Make sure you push them back into the whole a bit. I don't know if it is the metal the spiders don't like or that they can't maneuver through it but she said it is a non chemical alternative to help keep them out of the house. The weep holes are where a lot of spiders come in apparently. Cheap option to try anyway.