Can a Woman Do Household Duties when She Is Junub?
Question

Is it permissible for a woman to do her usual household duties such as cooking, looking after the children, and housework, before she does Ghusl following intercourse?
Praise be to Allah.Is it permissible for a woman to do housework when she is Junub?
It is prohibited for the person who is Junub (in a state of impurity following sexual activity) to pray, perform Tawaf, stay in the mosque, recite Quran or touch the Mus-haf. Everything else is permissible. 
There is nothing wrong with a woman who is Junub cooking, looking after her house , taking care of her children or fulfilling any other needs. This is indicated by several pieces of evidence including the following: 

It was narrated from Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) met him on one of the roads of Madinah when he was Junub. He said: I turned back and went and did Ghusl , then I came. He said: “Where were you, O Abu Hurayrah?” I said: “I was Junub and I did not like to sit with you when I was not in a state of purity.” He said, “Subhan Allah, the Muslim does not become impure.” (Narrated by Al-Bukhari, 279 and Muslim, 371) 

Ibn Hajar (may Allah have mercy on him) said: “This indicates that it is permissible to delay doing Ghusl from the time when it first becomes obligatory, and that it is permissible for the one who is Junub to go about his business.” (Fat-h Al-Bari, 1/391) 
The recommendation to hasten to do Ghusl after intercourse 
It is better for the one who is Junub to hasten to do Ghusl, lest he forgets that he is Junub. And it is recommended for him to do Wudu before he touches food and drink and before going to sleep. That is better than doing these things when he is Junub. But this Wudu is not obligatory, rather it serves to reduce the impurity, and it is recommended. There are a number of Hadiths concerning that, including the following: 

It was narrated that `Aishah (may Allah be pleased with her) said: When the Messenger of Allah (peace and blessings of Allah be upon him) was Junub and wanted to eat or sleep, he would do Wudu as for prayer. (Narrated by Muslim, 305)
It was narrated from Ibn `Umar (may Allah be pleased with him) that `Umar ibn Al-Khattab (may Allah be pleased with him) asked the Messenger of Allah (peace and blessings of Allah be upon him), “Can one of us go to sleep when he is Junub?” He said: “Yes, if he does Wudu then he can go to sleep when he is Junub.” (Narrated by Al-Bukhari, 283 and Muslim, 306)

An-Nawawi (may Allah have mercy on him) said: 
“This indicates that it is recommended to do Wudu and to wash one's private parts before doing all these things, especially if the man wants to have intercourse with a wife with whom he has not yet had intercourse. It is definitely recommended to wash one's private parts. Our companions have stated that it is disliked to sleep, eat, drink or have intercourse before doing Wudu, and these Hadiths indicate that. There is no dispute among us that this Wudu is not obligatory. This is also the view of Malik and the majority.” (Sharh Muslim, 3/217)
Shaykh Al-Islam Ibn Taymiyah (may Allah have mercy on him) said:  
“It is recommended for the one who is Junub to do Wudu if he wants to eat, drink, sleep or have intercourse again, but it is disliked for him to sleep if he has not done Wudu. It was proven in an authentic narration that the Prophet (peace and blessings of Allah be upon him) was asked, “Can one of us go to sleep when he is Junub?” He said: “Yes, if he does Wudu as for prayer…”  (Majmu` Al-Fatawa, 21/343) 
For more details, please refer to the following answers: 30784 , 20847 , 14225 , 7310 , and 10319
And Allah knows best.