Question: When dealing with required "clearances" stated on wood burning stove brochures, specifically the Vermont Casting line, (ie: "22' without optional heat shield" etc.) are they referring to walls of any material or just non-combustible surfaces such as brick or tile? I am dealing with a corner location which will have vinyl windows at the back and stucco-board to the sides. Obviously the Stucco-board is not ideal, but what kind of clearances should I be looking at now and/or what reasonably affordable replacement materials could you recommend? Answer: Clearances are usually given to combustible materials like sheetrock, wood, etc. The materials you mention would be classified as combustible. To reduce these clearances, you must have a "protected" wall.. Vermont Castings and others define this in different ways, but a sheet of wonderboard or durarock (cement board) mounted on spacers 1" from the wall passes the test. So does sheet metal mounted 1" off, as well as brick and stove with an air space behind it.