KITCHENER - Don't try this at home.

A Kitchener man sparked an explosion in his apartment that left him with severe burns when his attempt to make marijuana oil went awry. On Friday, Curtis Winthrop, 49, pleaded guilty to producing cannabis resin and causing an explosion.

After watching a video on the Internet on how to make marijuana oil, he gave it a shot. Winthrop bought butane from a convenience store and went to work in the bedroom.

The explosion on July 21 blew the bedroom door off its hinges and knocked the living room air conditioner out the window, prosecutor Kathleen Nolan told Kitchener court. The upstairs tenant felt the floor lift.

The blast also sparked a fire.

When emergency crews arrived, Winthrop was covered in soot and screaming, Nolan said.

He suffered severe burns and spent 10 weeks in hospital.

Damage to the apartment at 150 Heiman St., near Highland Road East, was just $1,695.

Winthrop's girlfriend and her adult son were in the apartment at the time. She was making dinner when she heard the blast.

Nolan said his girlfriend told him "1,001 times" not to make marijuana oil in the apartment. Winthrop maintained it was his first attempt.

Drugs found in the bedroom were worth $500.

Winthrop, who has prior convictions for growing marijuana, will be sentenced on March 13. A pre-sentence report and victim impact statements will be filed.