We forwarded your question to the office of grand Ayatollah Bahjat (may his soul rest in peace) and the answer which came to us is as under:
If the mortgage facility is received in the form of a sale [contract], there is no problem in it.
[Note: In an Islamic mortgage transaction, instead of loaning the buyer money to purchase the item, a bank might buy the item itself from the seller, and re-sell it to the buyer at a profit, while allowing the buyer to pay the bank in installments.]
For further information in this regard see the following indexes:
1. Index: Interest and Mortgage Loan and Car loan, question No.3364 (site: 3627)
2. Index: Using Loan for Purposes other than that which was first declared to the bank, question No. 2672 (site: 3044)
3. Index: Receiving Bank Loan or Bank Facilities, question 1225 (site: 1222).