Action News is told two men helped rescue the couple from their home in the unit block of South Ruby Street.
The collapse happened around 4:45 a.m. Wednesday.
The man, who had been lying on a sofa downstairs, said the couple's cat started acting oddly.
His longtime girlfriend told Action News she heard creaking and came to the top of the stairs.
The next thing both of them knew, the wall and ceilings gave way.
"We had just pulled up, and we heard crackling, and from the crackling there was a big boom," said an area resident who gave his name as Bones. "That was the wall coming down."
Bones and his friend Seth were parked near the home, having just returned from Sugar House casino.
After the house collapsed they saw the woman on the second floor, her boyfriend unable to retrieve her.
They scrambled into the rubble to help them out.
"We heard a scream," said Bones. "And we saw the woman dangling from the steps from the second floor, so we crawled up the side of the wall."
"While we were helping, the lady came down (along with) debris, sliding out of house," said Seth. "We just wanted to make sure everybody was okay."
Miraculously, neither the man nor the woman were seriously hurt.
A woman who spoke to Action News said her son lived in the home with his longtime girlfriend.
"He's doing well, but visibly he's upset," the woman said.
A woman who spoke to Action News said it was her son who lived in the home.
"He's doing well, but, visibly, he's upset," the woman said.
A bit of additional good news came later Wednesday morning, when the couple's cat, Baxter, was found alive in an upstairs room.
They got Baxter! Cat found alive inside upstairs of collapsed home. pic.twitter.com/bkqNJ03rUm— Katherine Scott (@KScott6abc) July 26, 2017
Video from Chopper 6 HD and the Action Cam showed the side of the standalone structure after it buckled.
The contents of the two-story home had spilled out onto a vacant lot next door.
House collapse in West Philly. No serious injuries reported pic.twitter.com/twkH86Nuce— Katherine Scott (@KScott6abc) July 26, 2017
The structure was originally built as part of a series of row houses.
Because the neighboring homes have long since been torn down, officials say, the home was already structurally compromised.
In addition, there has been construction work going on for several weeks next door.
It is not clear if any special bracing was put in place for the home that collapsed.
The mural on the side of collapsed home was called “I Wanna Call You Names". It was part of a project of 50 murals in West Philly. pic.twitter.com/GaFDzftZ2d— Katherine Scott (@KScott6abc) July 26, 2017
Action News has learned the side of the home that collapsed contained a well-known mural that was created as part of the Philadelphia Mural Arts Program.
The mural was called "I Wanna Call You Names."
It was part of a series of several dozen murals in West Philadelphia collectively called "A Love Letter for You" by artist Stephen Powers.
According the Mural Arts Program website, "Love Letter" is considered one of the program's most popular projects.
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