Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
What is the overall area of the whole plot upon which your house and side garden stand. Once I know this I can advise you further.
HMRC Helpsheet 283 states:
'If your garden and grounds do not exceed half a hectare (which is a little over 1 acre), you are entitled to relief for all of it'
Thus if this is the case, as you say it is, then it is within the 'permitted area,' half a hectare, and Private Residence Relief (PRR) applies to the whole holding which would be entitled to the relief. Thus any gain on the ultimate sale of part or all of the site would be entitled to PRR and this relief is at 100%; thus no Capital Gains Tax (CGT) to pay.
To obtain PRR on the whole shooting match the total plot must be within the premitted area. If it is so any sale of the plot or part thereof would be entitled to PRR.
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