分煙 'separation of smoking and non-smoking' (分 'divide' + 煙 'smoke') is a compact compound for the policy of separating smokers. ウチ 'our place / we' is the casual in-group first person. ~しなきゃいけない is the casual contracted must-form. よねぇ (with elongated ぇ) seeks agreement with a resigned, sighing tone.