Mr Jennians, who was known as Beau, was working at the Coach House in Abbotskerswell without proper safety equipment and precaution when he fell, the court heard
A gutter cleaning company boss has been jailed for five years over the death of a teenager who fell off a ladder.
Mason Beau Jennians, 17, died after falling while working in Devon in December 2014.
Colin Jeffery, 58, from Durham Close, Paignton, boss of Devon-based Utterley Gutterley, was found guilty of manslaughter by gross negligence.
At Exeter Crown Court police said Jeffery had a "total disregard for the safety of his employees".
Mr Jennians, who was known as Beau, was working at the Coach House in Abbotskerswell without proper safety equipment and precautions when he fell, the court heard.
Police said the "vast majority" of Jeffery's employees "were young men who were vulnerable to the risks of dangerous work by virtue of their youth, inexperience and inability to appreciate risk".
Det Insp Steve Davies, of Devon and Cornwall Police, said Jeffery engaged his staff "with a flagrant disregard for the regulations which govern work at height" with the sole aim "of providing a cheap quote to customers that would secure him work".
He said: "He completely failed to consider or implement even the most basic of safety measures.
"His working practices were inevitably going to lead to the serious injury and death of one his employees at some point in time."
Jeffery pleaded guilty to four other health and safety offences over work carried out at four other properties in the Torbay area.
HM Courts and Tribunals Service
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