my question is regarding the different ASR beginning times between Hanafi and all other mathabs. Sometimes when I am at my place of education where there a lot of shafies and hanafis, there can be a mix up when knowing which salat is being read when we go into the salat room. For example, a few Hanafi followers would have started a zuhr jamaat just before their Asr time begins but someone from the shafi background may come in late and join our salaat in the knowledge that we are reading Asr (since his Asr time would have started). My question is that would the salaat of the person who came late still be accepted/obligation fulfilled?
There are two issues regarding your question; a) Commencing time of Asr Salaat, and b) The validity of the Salaat of the follower joining Dhuhr Salaat with the intention of it being Asr Salaat.
According to Imaam Abu Hanifa, the commencing time for Asr Salaat is upon the shadow of any item extending twice its length excluding the shadow of midday. According to the majority Imaams, the commencing time for Asr Salaat is upon the shadow of any item extending till one length excluding the shadow of midday. This is also the view of the two famous students of Imaam Abu Hanifa ? Imaam Abu Yusuf and Imaam Muhammad.
Many authorities of Ashaab-e-Tareeh (jurists having authority of preference) have given preference to the view of the students of Imaam Abu Hanifa which is also the view of the majority of the Imaams. There is thus a leeway for Hanafis, especially in places where the Imaam is a Shaafi?ee, or there are many Shaafi?ee, etc. to perform Asr Salaat upon the completion of one length shadow of an item. It is our advice that the Dhuhr Salaat and Asr Salaat times be specified to avoid confusion. The time may also be adjusted to suit the adherents of the other Madhabs besides Hanafis.
The second aspect of your query is regarding a Shaafi?ee, for example, joining the Dhuhr Salaat performed by Hanafis during Shaafi?ee Asr time. The Asr Salaat of the Shaafi?ee follower will be valid. However, according to the Hanafi Madhab, the Imaam and follower must be performing one Fardh Salaat, for example, only Dhuhr Salaat. The follower cannot be performing Asr Salaat behind the Imaam who is performing Dhuhr Salaat.
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai