The Spencer Fire Department was called to the fire on 7th Street Southwest at about 12:45 Tuesday afternoon.
Spencer fire officials report that they observed heavy smoke on approach. They found a fire in the basement.
A basement bedroom sustained extensive damage, as did support beams on the first floor. The rest of the home had heat and smoke damage.
No cause has been determined, but it is known the fire started in the downstairs bedroom.
While damage is extensive, a dollar figure is not known.
Crews were on scene for three hours.
No injuries were reported.