The fire broke out around 7:30 a.m. in the 1200 block of Gail Road in West Goshen Township.
The victims are identified as 85-year-old Robert O'Neill and his wife 68-year-old Irene O'Neill.
On top of flames and smoke, fire crews faced an additional challenge.
"You could barely walk around, you couldn't get from one room to the next," said Lt. Greg Stone of the West Goshen Township Police Department.
Lt. Stone says the victims were hoarders who lived in deplorable conditions. Mounds of "things" fueled the fire and increased the risk for firefighters.
"You walk in and there was one to two foot wide paths to every room," said Lt. Stone.
The blaze was first discovered by neighbors who saw smoke coming from the roof.
Neighbor Jack Finley said the couple had been battling health issues.
"Their life was pretty difficult with his Alzheimer's and she had some health issues," Finley said.
Philip Bennie worked as the couple's caretaker. He said the couple loved birds and had dozens.
Bennie said he also tried to help Irene restore order in their home but failed.
Police tell Action News that several people tried to help. A township zoning officer and a fire marshal had visited the house and encouraged a cleanup.
Just last week, the Department of Aging visited the property. The department says details on the matter are confidential but the O'Neill's were given the care they needed.
Meanwhile, investigators say an electrical problem sparked the fire.
Even though storms were moving through the area this morning, investigators say lightning was not to blame.