The unidentified teens were treated for cuts at an area hospital, KOMO-TV, Seattle, reported.
A man who was in a back room of the house at the time of the blast was not hurt. He told police he hadn't known what the boys were up to.
The TV station said the teens allegedly had been experimenting with explosive materials, possibly fireworks.
The city police's arson and bomb unit was investigating.
Celebrity Couples of 2014 [PHOTOS]