Banks give loans only on the basis of original documents. It is almost impossible to get a loan without original legal documents. Therefore, banks will not give home loans on the basis of the original purchase deed and photocopy of the sale agreement. In case your certificate is lost or destroyed in some unfortunate event, you can obtain a certified copy issued by the Sub-Registrar. Some banks will accept this certified copy but it is not mandatory for the bank. Before getting the certified copy, you should have completed the process of FIR copy, non-traceable certificate, advertisement, and affidavit submitted to the sub-registrar. So it is very important to keep all these documents for availing a home loan. You can get Housing Loan even after the loss of the Sale Deed.