This paper introduces a cost-effective and robust positioning architecture that relies on wireless sensor networks (WSNs) for construction resources localization. The architecture determines the location of mobile sensor nodes by evaluating radio signal strengths (RSS) received by stationary sensor nodes. Only a limited quantity of reference points with known locations and pre-calibrated RSS in relation to pegs are used to lock on the most likely position coordinates of a tag. Indoor experiments were conducted, revealing that acceptable position estimation with 1-2 m accuracy can be obtained with this flexible sensor network architecture. To simulate the dynamic setting of a construction site, controlled experiments were also conducted by parking a car at various locations in the testing environment in order to evaluate the impact of imposed obstacles on location estimation performance. This localization technique is found to produce robust positioning results, thus paving the way for potential deployment in real-world construction sites.