WOOD WINDOW basics 101

The basic terminology of a wood window might seem a bit complex, so we wanted to take a moment to go through some of the common jargon you might hear to help you better understand your windows.

learning The Basics

The diagram on your right shows you many of the common parts to a wood window.  Below we will go into further detail on some of the terminology you will need to understand when discussing or reading through an estimate for your project.

  • Lower and Upper Sash – When we talk about your window, the two main pieces we are referring to are the sashes.  The majority of restoration work will be done on the sashes and not the actual window frame, sill or casing.
  • Interior Casing – You guessed correct.  It’s just the trim around the window.
  • Parting Bead – This is the “guide” that runs up the middle between the lower and upper sash.  When we remove your sashes, this piece of the window is typically destroyed and must be replaced when we reinstall them.
Wood Window Terminology
  • Interior Stop – To the untrained eye, it looks merely like a common piece of trim on around your window.  Upon closer review, it helps creates part of the “track” between itself and the Parting Bead to allow the sash to open and close.
  • Lite – Another bit of wood window jargon.  To the common Muggle it is referred to as a “pane”.  Wood wizards call them “lites” when discussing the number of separate pieces of glass in a sash.
  • Muntin – Not only is this a fun word to say but it’s also the small divider that creates more beauty in your wood window.  Over time, these can become damaged or rot due to extreme condensation and lack of proper care.
  • Stool/Apron – Most people call this the interior window sill but these are the technical names in case you want to impress your friends at your next party.


what makes a sash?

We already covered some of the minor parts like muntins but what actually makes a sash?  To the left you can see a diagram that outlines the major pieces of your wood window sashes.

  1.  Stiles – These are the left and right pieces of a sash.  They can suffer from mild to severe rot and may need to be replaced during restoration.
  2.  Rails – The top and bottom pieces of the sash.  The bottom rail is typically the one that must be replaced because it sets directly on the sill and if water gets caught underneath, the rail can literally fall apart from rot.
  3. Meeting Rails – Getting more specific, this is the bottom rail on the upper sash and the top rail on the lower sash.  Years of heavy condensation and a lack of proper sealing with paint or clear finish can cause these to get very soft and/or rot.


Historical Wood Window Facts – Double Hung

The majority of wood windows found in historical homes are double hung which means the upper sash actually works as it can be lowered.  It’s true!

Back when wood windows were installed, homes had no air conditioning.  By opening the upper and lower sash, the hot air escapes out the top and cool air flows in the lower.

Contact us today to have Restor Wood Windows come let the fresh air in!

Double Hung Wood Windows

sash configurations

There are a multitude of sash configurations and quite honestly too many to try and name them all.  So regardless of the configuration, we are going to focus on helping you identify the type of sash configuration in your own home and your local neighborhood.

Above are three of the most popular sash configurations you will find here in the Oklahoma historic districts located in Oklahoma City, Norman and Guthrie.  Because these are so prevalent in our area, we thought it might be nice to give you some examples you will readily see on a daily basis and many of you probably already have at least one of these in your home currently.

Anytime you want to determine the sash configuration of a wood window, you have to start with counting the number of lites in each sash (if you need to scroll up to review what a lite is then go ahead, we won’t tell).

[Upper Sash Total Lites] Over [Lower Sash Total Lites] ed-hrvatski.com

Looking at the first example, there are three lites in the upper sash and one lite in the lower sash.  The configuration is always notated by giving the total number of lites in the upper sash first and then the total number of lites in the lower sash last.  In fact, the format reminds you to put down the upper sash by adding the word “over” between the two totals because the upper sash is “over” the lower sash.  Therefore, you come up with the sash configuration of “3 Over 1”.


pop quiz – you ready?

You have read through the course material so let’s see how much you retained for the pop quiz!  Read the question, think of the answer and then click on the question to reveal the answer.  Good luck!

Congratulations on passing the exam!  Hopefully you learned some new words today that will help you better understand wood windows and how to more clearly communicate their needs to a professional wood window restoration expert.  Knowing the lingo is half the battle in winning the preservation war!

Do Your Wood Windows Need Help?

If your wood windows have any of the issues described above, we offer professional repair, restoration and reproduction services to help get your wood windows looking and working like new again.  You can click on the link below to read more about what Restor Wood Windows can do for you or simply fill out the form below to schedule a free consultation. 

Schedule a Window Evaluation

We would be glad to come by your home to review the needs for your wood windows and provide you with a free evaluation, estimate and timeline for when we can get started.

Text or call the number below or fill out the short online form to the right and one of our Restor Wood Window Specialists will contact you shortly to schedule a free window evaluation.


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