Series 9500 replacement double-hung windows come with standard double-strength, LoE2 glass that provides both energy savings and improved sound control, according to the manufacturer. The 7/8-inch insulated glass uses Intercept Warm-Edge spacers and is Energy Star-compliant in all 50 states. Other options include tempered glass, tinted glass, obscure glass, laminated glass, and argon gas fill. 800-234-4228. www.silverlinewindows.com.