It is recommended to offer voluntary prayers in one’s house although it is permissible to offer them in the masjid
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 " .
Jabir reported Allah's Messenger (ﷺ) as saying: 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.