Officials say a ventilation fan is to blame for the fire at a building next to a lighthouse in Gouldsboro.The building next to Prospect Harbor Lighthouse will most likely need to be condemned following a fire Monday, officials confirmed.The Hancock Maine Volunteer Fire Department received a report of a fire at the building around 5:13 a.m. Multiple units were called to the scene to assist in putting out the flames.Officials say the building is still standing but has extensive smoke and water damage. Fire rescue officials say the lighthouse was completely untouched, however.According to officials, a ventilation fan in the ceiling of a bathroom caused the accidental fire.