Abstract: The invention is directed to a portable data logging device for logging d concerning room identification and dimensions in a building or facility. The invention includes a microprocessor based portable computer having manual and automated inputs for logging data including a data port for room dimensions. An electronic distance measuring device produces an output indicative of one or more room dimensions in a digital format. An auxiliary processor responsibly coupled to the output of the distance measuring device converts the output to a coded format recognizable by the microprocessor. The data encoded in the coded format is coupled to the microprocessor via a voltage converter for recordation. The microprocessor may be programmed to step through a series of prompts, responses to which are stored in appropriate data locations for use at a later time.