Let me take an example to explain the situation : I sell my 1st house in X amount, buy another plot for Y amount and finally get floors built on that plot through builder for Z amount. This process overall takes 2.5 years. The Z amount I pay the builder through selling one floor. Finally I don't have any amount left with me, rather a loss.
Y (PLOT AMT) + Z (PAID TO BUILDER) > X (RECEIVED AMOUNT ON SELLING FIRST HOUSE) in 2.5 years
Example:
Y = 50 lacs, Z = 40 lacs, X = 50 lacs
Y+Z ( 50 + 40 ) = 90 > X (50 )
Do I need to pay any tax now?