Almost certainly it's the solid door doing most of the work. Doors and windows are absolutely terrible at keeping noise out. I had new windows recently installe

Almost certainly it's the solid door doing most of the work. Doors and windows are absolutely terrible at keeping noise out. I had new windows recently installed, laminated dual-pane, real beasts. In bedrooms that face the street, almost no noise, they're amazing. But in the front room where the front door is? The door might as well be open.