Sahih Muslim
Sahih Muslim 777 a
It is recommended to offer voluntary prayers in one’s house although it is permissible to offer them in the masjid
Arabic hadith text
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا يَحْيَى، عَنْ عُبَيْدِ اللَّهِ، قَالَ أَخْبَرَنِي نَافِعٌ، عَنِ ابْنِ، عُمَرَ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ "اجْعَلُوا مِنْ صَلاَتِكُمْ فِي بُيُوتِكُمْ وَلاَ تَتَّخِذُوهَا قُبُورًا "
Translation
Ibn 'Umar reported Allah's Apostle (ﷺ) as saying
Observe some of your prayers in your houses and do not make them graves.