Reading salah with a t-shirt
In the name of Allah, the most Beneficent, the most Merciful.
Answer
If a person without any reason reads his salah with a t-shirt or with his sleeves rolled above his elbows then it will be considered Makruh Tahrimi, if it is done with a reason then there are two views with regards to its detestability. Precaution is to avoid reading salah in such a way. (Ahsanul Fatawa p.406 v.3)
Only Allah Knows Best
Mohammed Tosir Miah
Darul Ifta Birmingham