Sahih Muslim 778
Sahih Muslim · Book 6: The Book of Prayer - Travellers · It is recommended to offer voluntary prayers in one’s house although it is permissible to offer them in the masjid
Jabir reported Allah's Messenger (ﷺ) as saying:
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ ، وَأَبُو كُرَيْبٍ قَالاَ حَدَّثَنَا أَبُو مُعَاوِيَةَ ، عَنِ الأَعْمَشِ ، عَنْ أَبِي سُفْيَانَ ، عَنْ جَابِرٍ ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِذَا قَضَى أَحَدُكُمُ الصَّلاَةَ فِي مَسْجِدِهِ فَلْيَجْعَلْ لِبَيْتِهِ نَصِيبًا مِنْ صَلاَتِهِ فَإِنَّ اللَّهَ جَاعِلٌ فِي بَيْتِهِ مِنْ صَلاَتِهِ خَيْرًا " .
When any one of you observes prayer in the mosque he should reserve a part of his prayer for his house, for Allah would make the prayer as a means of betterment in his house.