Income from house property

Deduction for Interest on HP can be claimed under sec 24.The amount of deduction can be categorized into two parts..

1.Pre construction Period Interest

2.Current Period Interest

The amount of pre construction period interest is the amount of interest paid from the date of taking the loan to the year in which the cinstruction is completed.It must be noted that the interest for the year in which the cinstruction is completed should not be brought under pre construction period Interest.

So you can claim the interest of the current year and pre construction period Interest.

The date of completion should not be taken as the date of loan.It must be taken as the date on which the registration is complete,all the conditions as mentioned in sec54 of Transfer of property Act are fulfilled then that may be taken as the date of completion of building.

The principal deduction can be claimed only for the period after the construction of property and the date of completion of construction can be considered as the same mentioned above

If you are constructing a new bulding you can take the date of completion construction  and till the date amount you paid towards interest on loan, you can get deduction U/S 24 as pre construction interest by dividing it into 5 years

Date will not be loan start date but the date of completion of construction..