Planting Peace founder Aaron Jackson said his organization bought the house across the street from the Topeka church, which campaigns against homosexuality, about six months ago, and started painting it in rainbow colors Tuesday.
Though the so-called Equality House isn't zoned for office use, Jackson, 31, said Planting Peace will use it to house volunteers who work on the group's equality campaign and bullying programs, The Capital-Journal of Topeka reported.
"This isn't us trying to start a war with [the Westboro Baptist Church] or anything of that nature," Jackson said. "This is just, they believe one thing and we believe another. We're opposing their view."
Steve Drain, spokesman for the church, issued a statement saying the church thanks God for the "Sodomite Rainbow House" because it shows how sodomy is destroying America.
"This is not a novel idea -- there are hundreds of similarly painted houses around the world -- the only reason why this one is a story is because of where it is!" Drain wrote.
Planting Peace was founded in 2004 to initially start an orphanage in Haiti, The Capital-Journal reported. The organization's projects later expanded to include deworming children in Guatemala and rainforest preservation.