Ruling on wiping over a cap or shemagh when doing wudu’
Question

Is it permissible to wipe, when doing wudu, over what is worn on my head, such as a cap or shemagh?
Praise be to Allah.Firstly:
There are soundly narrated hadiths from the Prophet (blessings and peace of Allah be upon him) which indicate that it is permissible to wipe over the turban when doing wudu. These hadiths refer to two ways of doing it:
The first way:
is wiping over the forelock [the front of the head] and turban. It was narrated from al-Mughirah ibn Shu‘bah (may Allah be pleased with him) that the Prophet (blessings and peace of Allah be upon him) did wudu, and he wiped over his forelock and over his turban and over his khuffs. Narrated by al-Bukhari (182) and Muslim (274).
The second way:
is wiping over the turban only. It was narrated that ‘Amr ibn Umayyah (may Allah be pleased with him) said: I saw the Prophet (blessings and peace of Allah be upon him) wiping over his turban and khuffs. Narrated by al-Bukhari (205).
Imam Ahmad (may Allah have mercy on him) acted in accordance with these hadiths. See: Kashshaf al-Qina‘ (1/120).
The majority of scholars are of the view that it is not valid to only wipe the turban when doing wudu, and that if someone does that, his wudu is not valid. We have discussed this previously and noted that the view of Imam Ahmad is more likely to be sound, in the answer to question no. 129557 .
Secondly:
With regard to the views of the imams regarding wiping over the turban, the cap and so on:
According to the Shafa‘is, part of the head must be wiped, then it is recommended (mustahabb) to carry on and wipe over the turban.
An-Nawawi said in al-Majmu‘ (1/440):
Our companion said: If he is wearing a turban and does not want to take it off for some reason, or even if there is no reason, he may wipe over all of his forelock, and it is recommended for him to carry on and wipe over the turban, whether he put it on in a state of purity or otherwise. If he is wearing a cap on his head and does not want to take it off, then it is like a turban, and he must wipe his forelock, and it is recommended for him to carry on and wipe over the cap too.
The ruling is the same with regard to what a woman wears on her head, but if a man only wipes over the turban and does not wipe over any part of his head, then that is not valid, and there is no difference of opinion regarding that in our view. End quote.
The Shafa‘is allowed wiping over the turban and cap, on condition that part of the head also be wiped. This is based on the fact that what is obligatory in wudu, in their view, is wiping part of the head, and it is not required to wipe the entire head. Hence they said that carrying on to wipe over the turban or cap Is recommended (mustahabb), but if they are not wiped over, wudu is still valid.
In the answer to question no. 70530 , we stated that the correct view is that it is obligatory to wipe over the entire head when doing wudu, and this is the view of Imam Malik and Imam Ahmad (may Allah have mercy on them).
According to the Malikis, it is not permissible to wipe over the turban except in the case of necessity, which is if the wearer fears harm if he takes it off. If part of his head is uncovered, he must wipe it, then carry on and wipe over the turban, and this is obligatory, as it says in Hashiyat al-‘Adawi (1/195).
It says in ash-Sharh al-Kabir (1/163), which is a Maliki book:
If he can wipe over part of his head, he should do that, then carry on wiping over the turban, and this is obligatory according to the correct view. End quote.
As for the Hanafis, they disallow wiping over the turban, despite the fact that there are hadiths which allow it.
See: Hashiyat Ibn ‘Abidin (1/181).
As for the Hanbalis, who allow wiping over the turban, the reason they gave for allowing it is that it is difficult to take it off. Based on that, wiping over the cap is not permissible, because there is no difficulty involved in taking it off.
Al-Bahuti al-Hanbali said:
It is not permissible to wipe over the large shawl [which is something that a woman wears over her head cover], because it is not difficult to take it off, so it is like the cap for a man, and it is not permissible to wipe over a cap. The reason why it is not allowed to wipe over them is because it is not difficult to take them off, so it is not permissible to wipe over them."(Kashshaf al-Qina‘  1/384).
Ibn Qudamah said in al-Mughni (1/384):
It is not permissible to wipe over the cap. This was stated by Imam Ahmad. End quote.
Thus it becomes clear that wiping over a cap and the like is not valid. Similarly, it is not valid to wipe over the shemagh, ghutrah or kufiyah (keffiyah) – these words all refer to the same thing [i.e., the scarf or headdress worn by Arab men in Saudi Arabia and other countries], except according to the madhhab of Imam ash-Shafa‘i, provided that part of the head is also wiped. This is because, as noted above, wiping the entire head is not obligatory according to Imam ash-Shafa‘i; rather what is obligatory is wiping part of it.
Contemporary scholars have issued fatwas stating that it is not permissible to wipe over the cap, shemagh and so on.
Shaykh Ibn ‘Uthaymin (may Allah have mercy on him) said:
It is permissible to wipe over a turban, for a man. The turban is that which covers the head and is wrapped around it, and that is something that is well known.
The evidence for it being permissible to wipe over it is the hadith of al-Mughirah ibn Shu‘bah (may Allah have mercy on him), according to which the Prophet (blessings and peace of Allah be upon him) wiped his forelock, and over his turban, and over his khuffs. The turban may also be called a khimar (head cover), as in Sahih Muslim: “He wiped over his khuffs and khimar. He said: That is, the turban.” Thus the word khimar was explained as referring to the turban. Were it not for this explanation, we would have said that it was permissible to wipe over the ghutrah if it is covering the head, just as it is permissible for a woman to wipe over her khimar."(Ash-Sharh al-Mumti‘  1/236).
Shaykh Ibn Jibrin (may Allah have mercy on him) said:
The cap is something that is worn on the head to protect it from the sun and heat, and it is shaped to fit the size of the head, but does not usually cover the ears. Therefore it cannot be compared to the turban with regard to wiping over it, because there is no difficulty in removing it. End quote.
Shaykh Salih al-Fawzan (may Allah preserve him) said:
The cap is not like the turban, and various types of caps and head covers do not come under the same ruling as the turban. The turban in particular is what is mentioned in the Sunnah with regard to it being permissible to wipe over it, so it should be limited to that. As for other kinds of head covers, such as the cap and tarboosh, and whatever is worn on the head, it is not permissible to wipe over any of them. End quote.
And Allah knows best.