Oedometer cells are commonly used in geotechnical engineering laboratory to determine the one-dimensional deformation of soil samples. The cell is simply a short open-ended cylinder, capped with a pair of porous discs, for containing the soil. Load is applied on the sample with a lever arm mechanism, which transfers the load from weights placed on a hanger suspended away from the oedometer cell. In the laterally-confined test condition, simultaneous measurement of radial stress of the soil sample under vertical load is understandably desirable, to obtain a more comprehensive picture of the soil’s behaviour at-rest. Direct measurement of the soil body is almost impossible in an oedometer cell, but radial stress can be indirectly gauged by instrumentation of the cell wall. This paper describes the design and building of an instrumented floating type oedometer cell, which concurrently measures vertical deformation as well as radial stress of stabilized soils. Based on fundamental hoop strain principles, 2 pairs of micro-strain foil gauges, perpendicularly arranged and affixed on opposite sides of the cell’s outer wall, were connected in a Wheatstone full-bridge circuit for maximum voltage output. The design, construction and installation procedure as well as calibration methods are detailed in this paper to illustrate feasibility of the instrumentation adopted. The technique can be easily duplicated for similar rigid type cells and provide an economical means of monitoring hoop strain, and hence redial stress of soils under loading.