A holidaying safety officer suffered a fractured skull trying to jump between two 20-foot high hotel balconies, because his wife was desperate for the toilet, a court has heard.

Normally "sensible" Philip Clay from Milford Haven took his life in his hands when he and his family were trapped on a balcony, having locked themselves out, and his wife Valerie told him she was dying to go to the loo.

The couple were on a Thompson package holiday at the 4-star Guayarmina Princess hotel, in Tenerife, with Mr Clay's mum and dad, Ken and Patricia, in July 2011 when the dilemma arose.

Rather than let his wife "suffer the indignity of urinating on a small balcony in front of his parents", "moderate and decent" safety officer, Mr Clay, tried to get across the two-foot seven-inch gap from his parents' balcony onto that of his and his wife's own room next door.

But he came to grief after setting foot outside the balcony guardrail and stepping on what he thought was a solid concrete ledge, which promptly collapsed.

The "ledge" turned out to be a purely decorative cornice - made largely of polystyrene - which dumped him 20 feet down onto the terrace below as soon as he put his weight on it.

Mr Clay, was left lying unconscious in a "pool of blood" for half an hour before his plight was discovered by hotel staff.

Screaming for help, his wife and parents were trapped on the balcony all the while and witnessed his plight.

Mr Clay has "fully recovered" from his injuries, but is suing tour operator, TUI UK Ltd, for damages, insisting the hotel breached safety standards.

At Cardiff County Court last year, Judge Seys-Llewellyn QC rejected "respectable and likeable" Mr Clay's claim "with regret".

But he is now challenging the decision before top judge, Lady Justice King, at London's Appeal Court.

The court heard that the family man worked as a fire safety and security officer with responsibilities for health and safety at a local refinery.

He had drunk a pint of bitter, a glass of wine and a single whisky with water over the course of the evening with his family, and was "not intoxicated" when he attempted the fateful move.

His barrister, Rob Weir QC, explained that the couple had decided to join Mr Clay's parents "for a talk and a drink" on the balcony of their room after putting the kids to bed, but that all four had ended up being trapped outside when the balcony door accidentally locked.

They spent 30 minutes shouting for help to no avail, before Mr Clay, who was wearing just his pyjama bottoms, tried to get across to the other balcony, where he knew the door into his room was unlocked.

He was standing on the cornice - which unbeknown to him was made of expanded polystyrene covered with a thin veneer of cement - when it came detached and he "disappeared", plunging to the ground below.

Judge Llewellyn said the family were, "impressively ordinary and considerate people, and of apparently careful background".

But, despite his "extreme sympathy", he dismissed Mr Clay's claim that the cornice was "part of the balcony" and should have been weight-bearing or featured a warning sign.

He added: "He stepped onto a ledge that he did not and could not know was safe, two floors up, when there was no threat or emergency.

"The risk of injury, if it was not safe to stand on the ledge, was obvious, and at two storeys up, life threatening."

Challenging that ruling, Mr Weir said Mr Clay's actions were perfectly understandable and justified.

"They had tried by sensible means to get out, then considered what else to do," he told Lady Justice King.

"They were imprisoned on a small balcony, four adults together. Mr Clay was concerned for himself and his family.

"He didn't want his wife to face the indignity of using the balcony as a toilet," the QC added.

"You can't expect a man to have his wife squat and urinate in front of his mother and father on a small balcony.

"The whole family thought it was a good idea".

The barrister went on: "In hindsight, of course, you would say, 'yes, of course I would use the balcony for my bodily functions rather than see my husband lying two floors below'."

Lady Justice King reserved her judgment on the case and will give her ruling at a later date.