A FATAL explosion which destroyed a house in York could have been caused by acid from an ants' nest corrding a gas pipe, an inquest has heard.

Paul Wilmott was killed when a gas explosion destroyed his home in Springwood, Haxby, on February 19 last year.

The first paramedic at the scene told the inquest he first thought the "complete devastation" was caused by "a possible plane crash".

York Press:

An inquest held today by coroner Rob Turnbull in New Earswick, heard Mr Wilmott died from a fractured skull and injury to the brain in the gas explosion, which was thought to have been caused by a corroded copper pipe dating back to the 1970s.

Forensic metallurgist Dr Elizabeth Geary from the Health and Safety Executive said a copper pipe between the kitchen and the living room had corroded in a "unique and localised phenomenon", which could have been due to a number of factors - including formic acid from the nearby ants' nest or chemicals in the building materials around the pipe.

The pipe had fractured so cleanly, investigators initially thought it may have been cut, but further research showed a series of cracks had developed at one specific spot between the living room and kitchen, thinning the walls of the pipe. 

Not long before the explosion, Dr Geary said, the stresses on the pipe had become so heavy , it could no longer support any external loads and it fractured completely, causing a gas leak.

Following the corrosion, the fracture could also have been caused by the ground swelling after heavy rainfall or flooding in the weeks prior to the explosion, but the exact cause of the fracture following the "stress corrosion cracking" could not definitively be determined.

She said: "I've never seen anything like it. From a personal point of view, it's really, really fascinating.

"[THERE WAS] an ants' nest very near to where the fracture occurred and that's astonishing because organic acids are known to attack copper."

York Press:

The scene of "complete devastation" at Springwood

Paramedic Andrew Hewitson told the inquest he arrived at the scene to find a "scene of destruction" and "complete devastation".

Mr Hewitson said: "My first thought was that it was a possible plane crash.

"To be honest it was something as a paramedic and personally I hadn't ever seen before. It was complete destruction."

Firefighters found Mr Wilmott's body under some debris to the rear of the property, but Mr Hewitson pronounced him dead at 08.06.

The inquest heard Mr Wilmott would usually get up between 6.45am and 7am, and leave the house between 7.45am and 8am. Mr Hewitson said when he examined Mr Wilmott, he was dressed as if ready to go out.

Mr Wilmott's son Ian, who lived in the house until 2015, said he did not believe there had been any gas problems at the property previously.

However, he said his father and his father's partner had "mentioned a strange smell in the house since the beginning of the year", although he had never noticed it during his regular visits.

Ian Wilmott said he first became aware of the explosion when a work colleague text him at about 8am to check he was alright.

He said: "On looking at a photograph from social media after this call, I realised the explosion had completely destroyed our house."

WATCH: Our report from the scene of the explosion on February 19, 2016.

Olivia Costello, Mr Wilmott's partner of nine years, lives in Saltburn-by-the-Sea, and said she first heard of the explosion on national radio and tried contacting Mr Wilmott by text and phone.

Ms Costello said she had stayed at the house in Springwood towards the end of January, when the couple noticed a strange smell.

She said: "It was very extreme and pungent.

"To me, it smelled like something had died. It was so horrible and strong, it made me feel sick."

The pair opened the windows and doors to try and diffuse the smell, then traced it to an area towards the rear of the ground floor. Ms Costello said they believed it may be a dead ant nest they knew was in one of the internal walls.

In a statement read to the inquest, Ms Costello - a former science teacher - said it had occurred to her and Mr Wilmott that the smell could have been gas, but after comparing it to the smell of gas from the hob, they were satisfied they did not need to contact the gas company.

The smell faded in the following weeks, and when Ms Costello stayed again in early February, it had mostly gone.

Mr Wilmott and his partner spoke on the phone the night before he died, and he did not mention the smell in the 40 minute call, and the pair made plans for Mr Wilmott to travel to Saltburn after work on February 19.

Ms Costello said Mr Wilmott's last words to her were "I'll see you tomorrow".

The inquest continues.