finishing basement reduces house value?I am thinking about finishing my basement...adding a bathroom and a bedroom. When I changed the information on Zillow, the value of my house went down. Why is that?August 21 2011 - Chantilly00YesReport a ProblemProblemSelect oneOffensive contentIrrelevant contentSpam (pure self-promotion)OtherDetailsYour emailPlease enter a valid email address.Submit CancelContent flaggedWe will review this content. Thanks for helping make the site more useful to everyone. To learn more, read Zillow's Good Neighbor Policy.We're sorry. This service is temporarily unavailable. Please come back later and try again.