Answered by Shaykh Shuaib Ally
Question: Is it permissible to write Quranic calligraphy directly on a wall?
I hope you are well.
Writing the Qur’an on the wall is, God willing, permissible, if:
-it is written in a proper, suitable environment
-it is highly unlikely that it will be open to abuse
-the writing is for a good purpose such as remembrance
Scholars across the schools have generally held that writing the Qur’an on the wall is disliked, not that it is impermissible (for example: al-Majmuʿ; al-Sharh al-Kabir ʿala Mukhtasar Khalil; Hashiyat ibn ʿAbidin).
This is because of the potential that:
-The letters will fall and will be walked upon, or that the walls themselves will be walked upon;
-It will be open to abuse, like defacement or vandalism;
-It will distract people from praying (such as if it is in a place of worship)
-It will be in places where impermissible activities occur
If this potential exists, it remains a disliked action.