The L-Concrete Block, so named on account of its shape, is an outcome of a careful study and search by the Agricultural Engineering Section of the Iowa Agricultural Experiment Station for a durable and economical type of construction for the walls of farm buildings. With normal costs for the constituent materials, concrete in the plastic stage as it comes from the mixer or mixing board is an economical building material. The problem of economical construction with concrete, therefore, depends upon efficient utilization of the material and labor. The L-Block reduces the amount of material usually required and greatly reduces the cost of placing the concrete in the building. With ordinary concrete blocks, or the so-called unit construction, much labor is required in making, handling and placing the blocks in the wall, while with monolithic construction the cost of forms is often excessive, exceeding in some instances the cost of the concrete.