Respected Shaykh, Assalamu Alaykum wa rahmatullahi wa barakatuhu. Do you consider acquiring a house as a necessity which makes it permissible to be involved in interest, especially in non-Muslim countries? الربا من أجل المسكن

All praise is due to Allah. May Allah's peace and blessings be upon Muhammad, his family, and all his companions.
Wa alaykum salaam wa rahmatullahi wa barakatuhu
To proceed:
A house is considered to be one of the basic necessities which a persn cannot do without, especially if it protects him from heat and cold. This was mentioned by a number of scholars. Therefore, if a person cannot find the means to get a home except through an interest-based loan, then in this case it is permissible for him to get an interest-based loan. This is because interest is not different from the rest of the impermissible things, and it is one of the things which are permissible in cases of necessity, as  was mentioned by the Malikite, Shafi'te, and Hambalite jurists. They mentioned a number of issues in which involvement in interest is allowed due to necessity. There is no difference in this case whether a person is in an Islamic country or a non-Muslim country because the ruling is based on necessity. So wherever necessity is found, the ruling will be applicable.
However, in this case and other cases where a forbidden thing is permitted due to necessity, a Muslim must be sure that his situation is that of necessity which permits involvement in the forbidden thing. A necessity is when a person does a thing which is unavoidable. It is incumbent to ensure that necessity does not permit involvement in a forbidden thing except under two conditions:
Firstly: It should be unavoidable to engage in the prohibited thing so as to avert harm.
Secondly: It should be certain that the impermissible thing will take care of the necessity.
However, in spite of all this, a Muslim should not forget that interest of all types; the interest of sales, and the interest of loans, is one of the greatest things which necessitate the anger of the Exalted Lord, and it was only permitted because of necessity. Therefore, if there is uncertainty as to whether these conditions are fulfilled in a certain case, then the original ruling which is that interest is forbidden should be resorted to. O Allah! Guide us, and save us from the evil of ourselves.

Shaykh Khalid al-Mosleh
24/11/1428 H