This spider is found across the world and in great numbers. They produce a brown paper sack in their web and are the shape of a teardrop. They will be found in man-made structures mainly and usually in areas that are left undisturbed like basements, crawl spaces, and unused rooms in the structure.
The best defense is to physically eliminate the spiders seen in corners, but if populations are high, glue boards and spot treating inside will be necessary. An exterior treatment can be done, but will not solve the problem entirely indoors.