polyurethane vs. shellac poly is a very durable product. With durability come some issues. Puts off some horrible fumes. I would not be in a house where poly was freshly applied. These fumes need to be ventilated. Don’t use poly during the winter months, when ventilation would be difficult due to weather concerns. Don’t sleep in a room with fresh poly applied. I could not imagine sleeping with all of those fumes. When you feel that the fumes are all gone, shut that room off and go back in later on that day and see if you smell any fumes. If the room still smells there not gone yet. Keep ventilating. Make sure the fumes are gone before you stop ventilating. If durability is your main concern Polyurethane is your product. You wont see me use poly in my house. I don’t care how durable it is. Shellac is not durable Shellac is easily recoated and provides a fresh shiny coated floor when reapplied. The alcohol smell that Shellac gives off is short lived. Alcohol dries quickly.