The building Josh Oliver set ablaze in Washington houses health services and an MP's office.
Joshua Oliver had been living rough near the Labour MP's office when he set fire to a bin store, a court hears.
Joshua Oliver, 28, who had been living in a tent near the building, will be sentenced in October.
Joshua Oliver, 28, is due in court in connection with the fire, which broke out on Thursday.
A spokesperson for Sharon Hodgson says the MP "will not be deterred".
The driver who knocked down and killed Gregg McGuire, 13, was given nine months in custody.
An independent panel will assess claims of wrongdoing at Teesworks, the UK's largest industrial zone.
