The Siteline (C) clad wood double-hung sash kit from Jeld-Wen pack includes a lower and upper sash, finishing jamb liners and all other pieces needed to replace a window using the existing frame.

Double Hung vs. Single Hung Windows: What's the Difference? With a double hung window, you can open the bottom sash by lifting it up, open the top sash by pulling it down, or open both for ...

These are the sash counterweights, and they connect to the upper and lower window sash with ropes or chains that run over pulleys at the top of the jambs.

They're usually more airtight than double-hung because the sash locks against the frame to close. When fully open, casements allow for good ventilation and easy cleaning.