What Is A Window Sash?

Are you shopping for new windows for your home? Or maybe you’ve noticed something about your current window that isn’t quite right. Whatever the case, one essential element of any window is the sash. Understanding what it does can help you make an informed decision regarding replacing or repairing your windows. This blog post will explain exactly what a window sash is, how it operates, and the features you should look for before purchasing. Read on to learn more!

This article covers the following topics:

  • What is a window sash?
  • Parts of a window sash
  • What windows have a sash?
  • Common window sash problems
  • Can you replace just one window sash?
  • Do all windows have a sash?
  • Sash repair vs replacement

What is a window sash?

A window sash refers to the frame around the glass in your windows. More commonly, the sash refers to the operable part of the window.


Parts of a window sash

An operable window sash comprises the frame surrounding the glass, the glass, attached locks or lift rails, weatherstripping, and options like an interlock and tilt-locks.


What home windows have a sash, and are they important?

Traditionally, operable windows are considered to have sashes. Vertical sliders like single-hung and double-hung windows, sliding windows, casements, and awnings have sashes.

Window sashes play a vital role in windows’ long-term construction and durability. Vinyl window sash frames must be multi-chambered, fusion welded, and reinforced to ensure optimal performance. Otherwise, they can become distorted, which results in leaking or locking issues over time.


Common window sash problems

Vinyl windows have gained market share and popularity because they are nearly impervious to window sash problems. Below, we’ll cover issues with different materials to see how vinyl became the most popular window choice across the US.

Aluminum sash problems
Popular from the 1960s into the 1990s, aluminum windows were the standard for four decades.

• As aluminum windows expand and contract over time, their joints separate. They separate because they’re screwed together. But, as the windows shift, those fastened corners start to separate, resulting in air and water penetration.

Wood window sash problems
Wood windows are beautiful and can be customized to meet your design tastes. Today, most custom homes are still built with wood window brands like Kolbe & Kolbe, Andersen, or Marvin.

• Like aluminum windows, wood window sashes are secured with fasteners. Over time, wood and clad windows will expand and contract after going through the seasons. After a few cycles, gaps can appear at the corners of your window. When this happens, air and water can penetrate the bottom corners of the window sash. Over time, even a tiny sash leak can lead to costly repairs like replacing a rotten windowsill or baseboard.

Vinyl window sash problems
• Vinyl windows tout fusion-welded frames. That means that the corner of the windows is heated and joined, creating a solid, continuous frame. With vinyl windows, there’s no way for the sash to separate. This keeps air and water from penetrating the sash frame and damaging your interior.


Can you replace just one window sash?

Yes. With wood windows, it’s common for only the bottom, operable sash to be damaged. Water runs downhill, so if water penetrates the corner of the sash, the bottom one is the first to go. Most wood window companies offer sash replacement kits instead of replacing the entire window.

However, we end up replacing many wood windows with vinyl windows, so you don’t have to worry about replacing sashes for another 25+ years. Vinyl window sashes can be replaced as well.


Do all windows have a sash?

Technically, every window has a sash. But most sashes refer to windows that operate.


Is it cheaper to repair or replace a sash?

Most window sashes have a bar code identifying the parts and pieces that make up the sash. While some individual parts can be replaced, like the glass, locks, or lift rails, it’s rare for a window company to take on such a small repair job. While it is cheaper to repair than replace a damaged sash, you may have difficulty finding a reputable company to come out and perform the repair.

If you are looking for sash repair services, we recommend a company like Mr. Handyman.

In closing

A window sash is an essential component of your windows. We hope this article detailing what it is and answering some common questions helps you buy the right windows for your home. If you live in DFW, we would love to help you choose the right windows for your home. Please give us a call or stop by our showroom today. Thanks for reading!