window sash

All About Window Sashes

Contrary to popular belief, shopping for replacement windows is probably more complicated than you once thought, especially with all the manufacturers’ jargon flying around, leading to confusion.

If you are looking to become a more educated consumer, here are a few essential things you should learn about its majesty: the sash.

What Is a Window Sash?

The word “sash” refers to all the components surrounding a window pane, and the window pane itself. There are two sashes in both single and double-hung windows, with the only difference between the two is the way they operate. Namely, the lower sash of a single-hung window is the only one that opens while a double-hung window has both the upper and lower sashes opening. For clarity, sashes are referred to as “fixed/inoperable sashes” and “operable sashes.”

Parts of a Window Sash

There are several components to a window sash, most of which you hear about from installers and manufacturers but can’t link to notions. These are some terms you should recognize:

Rails and stiles

Two borders surround a window pane; the left and right vertical edges are called stiles while the top and horizontal bottom edges are called rails. Materials such as wood, vinyl, fiberglass, or aluminum are used to create the border surrounding a window pane, and it typically matches the material a window frame is made of.

Sash lock

This piece keeps the window closed for security purposes. There are several types of sash locks:

  • Awning and casement windows lock against the frame
  • Sliding windows lock at the meeting stile
  • Double- and single-hung windows lock at the meeting rail

Sash pulls

To make opening the window easy, you’ll see that the operable sash of a sliding window has handles, indentations, or raised areas on the left and right vertical stiles.

Tilt sash release

For everyone who’s got modern double-hung windows, you should know that the tilt-in design engages the tilt sash release, making window cleaning easy from the inside of your home.


Glazing is another word for “glass;” basically, when you hear installers talking about a single-, double-, or triple-glazed windows, they are talking about windows that have one, two, or three layers of glass. The more glazing there is, the higher efficiency of the windows.


These are used purely for aesthetic reasons; they are the thin grilles that divide a window pane into smaller segments. Muntins aren’t the same as mullions; mullions are thick components that separate adjoining windows from one another.

Gas in-fill

A gas in-fill is usually used in double- and triple-pane windows to increase their insulating ability. Common gas in-fills are argon and krypton, both of which are safe and inert.

Sash Replacement Kits

Sometimes, breathing new life into your older home doesn’t have to mean a whole new window but a simple sash replacement. Sash kits can be both standard and custom size, to fit impeccably into your existing window frame. Replacing sash instead of windows saves you a significant amount of money.

If you feel like it’s time you have your sashes replaced, click here for a FREE estimate from 1-800-HANSONS. Our professionals provide installation estimates and window replacement options that will help your home get a new shine.