I finally found a way to rid buildings of cob webs and the daddy long legs and other little spiders that have been like a plague around here. these things just seem to love to get all over my tractors and lawn mowers and everything else.
in a pump up 2 gallon sprayer mixed 1/2 gallon water, 1/2 gallon or a little less of white vinegar, 1 ounce peppermint essential oil and a couple squirts of dawn dish soap.
seems to work real well and costs a heck of a lot less than the stuff they sell at farm store in spray cans. the vinegar kills em on contact and the peppermint keeps more from moving in and the soap help the mixture stick.