Ruling on covering the bier of the deceased
Question

                Is it permissible to uncover the face of the deceased inside the grave? What is the evidence for uncovering the bier of the deceased, for men, during the funeral procession?.
Praise be to Allah.
    Firstly: 

    It is not permissible to uncover the face of the deceased 
    when he is placed in the lahd (niche in the grave), whether the deceased is 
    a man or a woman. For more information please see the answer to question no.
    48959 

    Secondly: 

    With regard to covering the deceased, many of the scholars 
    (may Allah have mercy on them) regarded it as mustahabb to cover the bier of 
    a woman. That was narrated from some of the Sahaabah (may Allah be pleased 
    with them). 

    An-Nawawi (may Allah have mercy on him) said: It is mustahabb 
    to use a na‘sh for a woman. The na‘sh is a frame that is placed over the 
    woman on the bier, and is covered with a cloth so as to screen her from 
    people’s eyes. … They quoted as evidence for that the story of the funeral 
    of Zaynab the Mother of the Believers (may Allah be pleased with her). It 
    was said that she was the first Muslim woman to be carried on a bier covered 
    with a na‘sh. Al-Bayhaqi (may Allah have mercy on him) narrated that 
    Faatimah, the daughter of the Messenger of Allah (blessings and peace of 
    Allah be upon him, and may Allah be pleased with her), left instructions 
    that this should be done for her, and they did that. If this report is 
    saheeh, she died many years before Zaynab. As for the report narrated by 
    al-Bandaneeji, that the first time this was done was in the funeral of 
    Zaynab the daughter of the Messenger of Allah (blessings and peace of Allah 
    be upon him), and that the Messenger of Allah (blessings and peace of Allah 
    be upon him) ordered that that be done, this is untrue and is not known; I 
    draw attention to it so that no one will be deceived by it.

    End quote from Sharh al-Muhadhdhab, 5/234 

    In Haashiyat ad-Dasooqi (1/418) it says: It is 
    recommended to conceal the dead woman with a frame to be placed on top of 
    the bier, because it is more effective in covering. End quote. 

    Ibn Qudaamah (may Allah have mercy on him) said: It is 
    mustahabb to place over the bier of a woman something made of wood or palm 
    branches, like a frame, over which a cloth should be placed, to be more 
    covering for her. 

    End quote from al-Mughni, 2/211 

    Al-Bahooti (may Allah have mercy on him) said: It is 
    mustahabb to cover the bier of a woman with a frame.

    End quote from Daqaa’iq Ooli’n-Nuha, 1/369 

    The texts of the scholars which speak of it being mustahabb 
    to cover the bier of a woman with a frame indicate that a man should not be 
    covered, rather he may be left uncovered (i.e., with no frame over his 
    bier).

    Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said: 
    Should a makabbah be placed over the bier or not? 

    The makabbah is like a frame made of bent sticks that is 
    placed over the bier, and a cloth is placed over it. 

    Answer: if the deceased is female, then yes. Many of the 
    scholars regarded it as mustahabb because that is more covering for her. 

    Al-Bayhaqi (may Allah have mercy on him) narrated that 
    Faatimah, the daughter of Muhammad (blessings and peace of Allah be upon 
    him), left instructions that that should be done for her. 

    This is done in the Hijaz, but in Najd it is not known, 
    however if someone does it, he is doing something good and should not be 
    denounced for it, because sometimes there are funerals of women in which one 
    may see things that one does not want to see, but if they put this makabbah 
    over her, that would cover her. 

    It says in ar-Rawd: If the deceased is a woman, it is 
    mustahabb to cover her bier with a makabbah, because that is more covering 
    for her, and it was narrated that this was done for Faatimah on her 
    instructions. And a cloth should be placed over the makabbah. The same 
    applies if the deceased was a hunchback or the like, so as to conceal this 
    deformity. 

    In the case of a man, it is not Sunnah to do this; rather he 
    should be left as he is, because there is a benefit in that, which is the 
    powerful lesson to be learned by those who were with him yesterday and see 
    him now, a dead body on this bier. But if he is covered with an abayah, as 
    is done in our country, there is nothing wrong with that.

    End quote from ash-Sharh al-Mumti‘, 5/356 

    And Allah knows best.