The total amount of lifted weights and lift frequency are moderate to strong risk factors for lower back pain. Measurement of carried weight is thereby of interest. The aim of this paper is to (1) present three novel analyses methods for estimation of weight during walk and (2) to describe the design process of the cost-effective research system IngVaL based on pedobarography. The paper will also (3) present the durability of the sensors. Motivations for choices in the system design are given for hardware, selection of sensor type, sensor implementation and calibration of sensors. To measure weight during walk with IngVaL, fifteen test persons made five walks each with a pseudo-random added extra weight. Three analyses methods were tested, for estimation of weight while walking, resulting in Root Mean Square Errors of 11.3 kg, 7.1 kg and 6.1 kg respectively. The durability of the sensors were tested in an outdoors walking condition. It can be concluded that the IngVaL system shows good durability and that weight during walk is possible to measure with simple analyses methods.