Best practices on window sill attachement

What is the best way to attach the sill ? The attached pic is a mock up I’m doing on a 4′ wide window, but I also have 10′ wide… What is the best way to attach the sill ? The attached pic is a mock up I’m doing on a 4′ wide window, but I also have 10′ wide…Read MoreGreenBuildingAdvisor