Teaching quality in Islamic boarding schools (pesantren) is often attributed to inadequate learning facilities and uncomfortable classrooms. How teachers themselves perceive and experience these conditions in the pesantren setting remains little explored qualitatively. This study examined teachers' perceptions and experiences of integrated learning facilities and classroom environmental comfort in relation to their teaching at the Darussa'adah Islamic Boarding School Foundation, Nganjuk. Using a qualitative single instrumental case study, the researcher gathered data through in-depth semi-structured interviews, participant observation, and document review from eight informants: the foundation leader, the principal, four teachers who constitute the entire teaching staff (a complete census), and two senior students for cross-verification. Analysis followed an interactive process of data condensation, data display, and conclusion drawing and verification. Trustworthiness rested on source and method triangulation, extended engagement, member checking, peer debriefing, and an audit trail. Three themes emerged. First, integrated facilities served as both a motivator and a constraint: teachers valued them when they were reliable, but their limited numbers, unequal access, and lack of maintenance often made them an obstacle. Second, teachers experienced classroom comfort, especially heat and traffic noise, as shaping their psychological well-being, vocal endurance, and instructional delivery. Third, teachers reported teaching best only when reliable facilities and a comfortable room occurred together. The study offers a context-bound account in which teacher well-being links the physical teaching environment to instructional quality, and it has practical value for prioritizing maintenance and classroom comfort in pesantren