In sensor networks, a binding is an association between a sensor and an actuator. Both manual binding and semi-automatic binding mechanisms are inconvenience for a large number of sensors and actuators, and hard-coded automatic binding mechanism is not flexible enough. In this paper, we propose an automatic binding mechanism, which specifies a modeling method for sensing events and actuating actions, and with appropriate binding-rules, generates reasonable binding specifications automatically. Our implementation integrates several standard ZigBee sensors, actuators, and a web-based user interface. The implementation also achieves household applications including comfortableness, security, and safety.