Hello, You can calculate the styrofoam quantity by assigning the structure component in the flooring settings. In the Ribbon menu -> Tools-> Design Building Components 1-Click open a new category or create material in existing categories. 2- Write Styrofoam in the name of the material and select it proportionally to the area in the ratio section. 3- Calculate the amount of styrofoam in m3 according to the thickness and intervals you will choose on 1 m2 area. Write the calculated value in the amount ratio 2. Click OK. 4-Select all the tiles with hollow blocks, enter the tiling settings, click on Add Building Components, select the material named Styrofoam you created. In the Ratio section, select the upper area. 5-Click on the Ribbon menu -> Tools-> Building Components Quantity. Select the building components report grouped by components and click OK.