Sec 54 exemption

There is no tax exemption on capital gains spend on renovating house – Here is the reason
As per Section 54 of Income Tax Act, any long term capital gain arising from the sale of a residential property shall be exempt to the extent such capital gain is invested in the purchase of another residential property within one year before ortwo years after the due date of transfer of the property sold or construction of residential house property within a period of three years from the date of transfer/sale of property.

We can construct residential house. is it possible that 1st floor construct on existing house?????

You have to justify your step. it appears to be possible to get 54 advantage

Is it justify that 1st floor constructed

Yes you can

Krishna @ r u sure sir that I can use money for construct 1st floor of existing residential house for getting exemption u/s 54. plz check and conclude. thanku