A:AnswerHello! The width of this model is 21-1/2". Should you need further assistance, please contact us directly at 800-374-4432 M-F 8:30 am- 8:00 pm. ~Briana
A:AnswerNo
Built in needs only the front open for ventilation.
This units airflow is on the back of the unit.
Your builder would have to make a extra large opening allowing air to circulate all around it. There are built in units that vent on the bottom front so the install opening is to just big enough to allow a snug and “level” fit.