Windows are a major investment. They need to bring the outside in when you want, but also have to keep the elements at bay when you don’t. The options for style, function and performance can be overwhelming. Below are five things to consider before you purchase replacement windows, and tips on deciding whether to repair or replace.

Lingo to know:

Sash: A moveable frame that holds the window glass; a double-hung window is made up of two moveable sashes
Mull: To join two or more windows together
Muntins: Strips of wood that divide the sash into smaller sections of glass, which are called lites
R value: A measure of the efficiency of insulation; the higher the value, the more insulation
Flashing: A thin layer of metal or other waterproof material that keeps water out of joints at corners and changes in material