The Ultimate Guide to Sash Window Parts

When planning the installation of your new sash windows, it can be difficult to tell your joggles from your stiles, so we have put together a helpful glossary of terms to help with not only naming but really knowing each part of your sash window – and how each individual component works together to create that classic end product.

We know sash windows inside out, and we want you to know them as well as we do.

If you need more help figuring out what is what, or if you would like to explore options for your own sash windows, get in contact today – there is no ultimate glossary test, never fear, we will be leaving that job to this post.

What Is a Sash Window?

First, we best go over the Cliff Notes of what a sash window is before we get into the nitty-gritty of what makes them. 

  • A sash window is made up of two frames, one ahead of the other, and opens vertically. 
  • They are usually features of older builds (best suited to Georgian, Victorian, and Edwardian properties).
  • They utilise weights and cords in order to counterbalance the moving pieces – allowing for a smoother open and close.
  • Like casement windows (that feature adjustable panels to better-direct airflow in a room), sash windows offer brilliant ventilation capabilities. Sash uPVC windows are particularly good, with their ability to open both from the top and bottom.

For a more detailed guide on what a sash window is and what makes them essential, check out this post.


Outside Lining

Put simply, this is the outline of the sash itself, surrounding the exterior portion of the window frame or box. All of our outside linings are made from the highest quality timber.


Another one that is nice and easy, and also by far the most important part of your sash window, the glazing is the glass panelling of the sash window. 

Horn (or Joggle)

This feature is a decorative one and is usually only found in traditional sash windows. They are short extensions of the upper or lower sash, found on either side of the frame on the meeting rail. Aside from aesthetics, horns function as strengtheners to the overall frame. If you want to know more about Horns, we have written a handy blog post you can reference.

Bottom rail

This rail runs along the bottom sash. The rail is deeper than the other rails on the sash to leave room for the cill.

Sill (ext.)

Finally, right at the bottom comes the sill (or cill). It is designed specifically to allow better run-off for water and is usually made from hardwood. You can find the sill right at the bottom of your sash window frame.

timber casement window in a childs bedroom


Top Rail

This is a metal rail that runs along the top of the upper sash.


Usually found within the room, as opposed to the outdoor facade of the building. The Architrave is a shaped perimeter that covers the sash window frame. Depending on the style of the property, the Architrave used can be quite decorative or stylised – especially Victorian mouldings.

Staff Bead

Not a bead, as the name suggests, but a long strip of wood – and a section essential for holding the bottom of the sash in place, often fixed into the inside lining with nails or screws.

Sash Bars

Easy to spot on most sash windows, these wooden bars are what make up the grid-like frame that separates the panes of glass (or Glazing). Other names include Glazing Bars and Sash-gut. 

Meeting Rail

Sometimes referred to as Meeting Bars, but their purpose is always the same: the bar is found along the bottom of the upper sash and the top of the lower sash. The bars β€˜meet’ when the window is closed, hence the name. 

Inside Lining

The Inside Lining is a timber frame that makes up both sides and the head of the box frame. This is the part of the window that the Staff Bead, from above, is attached to.

Sash Stile

These wooden bars run up the left and right sides of the window frame.

Window Nosing

When in reference to windows other than sash, this area is called the Window Board – which is the length of wood at the bottom of the window where ornaments will be displayed, or cats will be napping. But most sash windows, due to how they are set into the masonry, will not have the room for a full Board, so instead will have Nosing, which is found in the same place but is usually not large enough to be used for anything decorative. 

Sill (int.)

The same as the exterior sill, but found on the inner side.

Get in touch

If you need any more information, or for guidance on choosing and installing your own sash window box, feel free to fill out our online contact form and we can schedule a callback for a time that is convenient to you.