Long Term Capital Gains

[Shahdan Calcuttawalla]

Hello

I wanted some clarification on when the clock starts ticking for counting the number of days towards capital gains. I bought a burnt down home in Dallas, TexasAugust and demolished it in September. The construction is due to be complete in May. 

So now my question is can does the number of days held start from when i bought the burnt down home and essentially if i wait till August then i can claim its as Long Term Capital Gain or does it start from when the New Construction is completed and i have to wait a full year from then to claim Long Term Capital Gain benefit ( which i wont)

Your input will be much appreciated. Thank You.