We propose RedirectedDoors, a novel space-efficient technique for redirection in VR focused on door-opening behavior. This technique manipulates the user's walking direction by rotating the entire virtual environment (VE) at a certain angular ratio of the door being opened. This ratio is called door rotation gain. At the same time, the virtual door's position is kept unmanipulated so that a realistic door-opening user experience can be ensured. We designed and implemented the rotational manipulation algorithm and two types of door-opening interfaces; with and without a doorknob-Type passive haptic prop. We then conducted a user study (N = 12) to investigate redirection performance and user feedback as we examined three independent variables: door rotation gain, door-opening interface, and door-opening direction (push/pull). From the results, the estimated detection thresholds generally showed a higher space efficiency of redirection with our technique. Our results also showed that providing the haptic feedback led to a higher noticeability of redirection, but at the same time supported a higher subjective sense of realism and less discomfort. Following our results, we discuss which combinations of gain and door-opening direction can jointly provide lower noticeability and higher acceptability.