I bid mulch and straw for 2 -3'' depth. Depends on what is below it. You'll have a hard time applying 1'' and effectively covering what is below. My labor rate would go up if I'm instructed to do only 1'', and that is if I took the job at all. 1'' wouldn't meet the quality standard that I live by.
Landscape management, design, and installation
Horticulturalist with Specialization in Landscape Management
25 years old 7 years in business ownership