The Judge, Mr Philip Richards, said the fire was a "very irresponsible act" with "consequences that were devastating". He acknowledged that Mr Goulding has considerable learning difficulties which is why he took so long to accept responsibility.
Mr Goulding has been remanded in custody and will be sentenced tomorrow at 2pm at Newport Crown Court.
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Robert Sparey also admitted trying to sell fake cigarettes and tobacco and attempting to persuade witnesses not to give evidence.
It will be a dry and bright day with lighter winds and some decent sunny spells making it feel pleasantly warm.
Gillian Griffiths admitted she was using the pads for her pet cat who was experiencing 'continence problems.'