He left behind a wife, Michele, and a young son, Luke.
"It was my fault. I should have looked at those guys working, and I didn't," Wagenhoffer said in a video message, which was obtained by NBC10, that he recorded on his cellphone before shooting himself. "When I saw it was too late. I should have parked my truck and went over there but I didn't. I'm sorry."
Wagenhoffer said in the video that he couldn't sleep because of the deaths, the news report said.
Those who knew Wagenhoffer described him as a kind, pleasant man who was always eager to lend a hand - and who was also undoubtedly haunted by the fatal building collapse.
City officials were quick to note that they had no issues with the job Wagenhoffer - who worked for the Department of Licenses and Inspections for 16 years - did while inspecting 2136-38 Market St. in February or when he returned May 14 to examine a permit issue at an adjacent property.
"I will state right here, right and now, this man did nothing wrong," Everett Gillison, Mayor Nutter's chief of staff, said yesterday. "The department did what it was supposed to do under the code that existed at the time, and we are proud of the department and its employees - period."
Word of Wagenhoffer's shocking death traveled quickly yesterday to a tidy block in Manayunk where he once lived.
"He was such a nice guy. He was always there if you needed anything," said Doris Stickle, 70, who lived a few doors away from Wagenhoffer and his family on Krams Avenue near Manayunk Avenue.
Stickle said Wagenhoffer, who was a groomsman in her daughter's wedding, used to sometimes sit outside his house and strum a guitar. And he always doted on his son.
"His little guy is going to be devastated," she said. "He was always with his dad."
Stickle said she learned that Wagenhoffer had inspected the collapsed Market Street building only when her daughter called yesterday to share the horrible news. "I'm sure it preyed on his mind," she said. "It's a shame he didn't reach out to anybody."
Wagenhoffer's family declined to comment.
His Facebook page depicted him as an avid outdoorsman who liked to hunt and fish, and who enjoyed working for Licenses and Inspections.
Gillison said Wagenhoffer was "a dedicated civil-service employee who loved his job." He continued to work in the days after the Market Street tragedy unfolded.
It was unclear if he expressed any suicidal thoughts to anyone.
"You have to understand that there are now five investigations going on," Gillison told reporters at a news conference at City Hall. "You will get the answers to the questions you have at the appropriate time and at the appropriate place."
In 2011, Wagenhoffer was nominated for an L&I award given during Building Safety Month to a leader of the agency's construction-code enforcement division.
The L&I office at Spring Garden Street near 10th, where Wagenhoffer worked, closed yesterday and was expected to remain closed today. Upon learning of their colleague's death, employees there were offered to take the day off, said Nutter's spokesman, Mark McDonald.
- Staff writer William Bender contributed to this report.
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