"The whole thing had collapsed in on itself, but we were on the scene for three hours," he said.
The Dannevirke brigade was called to the property again at 7.30am yesterday when a shed burst into flames again, probably fanned by wind, Mr Sinclair said.
Mr Reynolds said he and his family were taking the events of Saturday night hard.
"My wife was distraught when told what had happened, but I don't think the shock has really kicked in for me yet, but it will," he said.
While Dannevirke CIB and the Fire Service investigation officer Mike Finucane were searching for clues to the cause of the fire on Sunday morning, Mr Reynolds was trying to come to terms with what had happened.
"I know there had been nothing left on which was likely to have caused this, because we hadn't been home all day. But we had been back and forwards briefly," he said.
A Dannevirke police spokesperson said the fire was being treated as suspicious, until a cause was known.
Mr Reynolds said he didn't know of anyone who would want to destroy his home.
"We haven't annoyed anyone and I'm buggered if I know what to think, I'm just despairing at what has happened," he said.
The couple were insured.
In May 2009 a farm cottage across the road from the Reynolds' home, owned by a neighbouring dairy farmer, was also badly damaged by fire.
Dannevirke deputy chief officer Peter Feierabend said the latest blaze was being investigated, but the extensive damage to the home would make the case more difficult.