A - What is my rough-in? 12” from the wall to the center of the toilet trap. B - Where is my shutoff valve? Type B1 - The shutoff valve will be positioned outside of the toilet base if it is more than 6.25“ from the center of the trap when measured along the wall. Type B2 - The shutoff valve will be positioned inside the toilet base if it is less than 5”. C- R If the shutoff valve is positioned between B1 and B2, it must have a depth of less than 4” to allow for proper installation.