Hadith 4:787
9653. Abdullah bin Numayr narrated to us, from Abd al-Malik, from Ata, who said: When Ibn Umar wanted to perform i'tikaf, he would set up a tent or a pavilion, and he would fulfill his needs in it. He would not go to his family, and he would not enter under a roof.
حدثنا عبد الله بن نمير عن عبد الملك عن عطاء قال كان بن عمر إذا اراد ان يعتكف ضرب خباء أو فسطاطا فقضى فيه حاجته ولا يأتي أهله ولا يدخل سقفا