Must you plant an evergreen hedge when a semi-evergreen flowering shrub is fine for the task?
Leatherleaf viburnum hybrid cultivars 'Allegheny' and 'Willowwood' are 60% evergreen, dropping their foliage very late in autumn in U.S.D.A. zones 6 and 7-a. 'Willowwood is preferred over 'Allegheny' in areas of zone 6 and 7 where powdery mildew disease may be a problem.
Prague viburnum (Viburnum pragense) is the only "true" evergreen viburnum. It possesses lustrous dark green foliage year-round and grows to 9-10 feet. Its height is tall enough to become a beautiful privacy screen and noise barrier from the neighbors and traffic.
All three viburnums are excellent growers. They have a distinct advantage over most conifer species used in privacy screening. These lovely viburnums flower in late spring and early summer, something the conifers don't offer.