What is a Window Jamb?

Are you wondering what a window jamb is? If you are then you are in the right place. If you plan to hire a window installer and want to know more about window jambs please read on.

The window jamb is one of the most crucial parts of a window. There are three types of jambs, one on each side, which are called the side jambs and one above at the top known as the head jamb. All these jambs provide great structural support allowing the window panes to stay in their place within the frame

In order to achieve this they need to be placed between the glass of the window pane and the window frame.

What are Window Jambs?

Window jambs are scaffolding like a framework that supports it and keeps it in the right place. This is especially important for windows that can be opened because they have tracks or rails which allow them to be opened. These allow them to slide up and down as well as side to side.

They also have latches or locks to help keep the window secure. Window jambs can be made from wood, plastic, vinyl and steel. But it is important to note that they aren’t compulsory to use in windows.

Many companies which make windows also manufacture marching jambs and jamb extensions that can be used to allow their products to fit well. A jamb can act as a weak point in a window if they aren’t installed properly, causing leaks and security issues.

Window jambs can be painted to match the trim of a fixture, depending on the material and the overall aesthetics of your structure. If your windows begin to move unevenly and gaps appear around the window, replacing the jamb may solve the issue and cost less than replacing or reframing the whole window.

  • Window jambs can save energy making your windows energy efficient
  • Window jambs are manufactured by companies that make doors and windows
  • Its best to consult a professional to replace or install  a window jamb

Can I Replace Window Jambs on my own?

If you have prior experience in replacing window jambs or carpentry then you can give it a try! It is important to get a clear understanding of the proper steps before attempting to replace window jambs by yourself. Make sure that you have all the hardware needed before you start off.

If you have the skills, then you can use them to craft jambs or new windows and to replace one to remove rot, leaks and warps. It is important to ensure that the jambs fit snugly in their proper place.

Jambs that have openings might lead to water damage and there is a chance of the replacement windows slipping out of the frame.

If you don’t have the skills to install jambs then it’s best to get in touch with a window installation contractor. This will save you time and guarantee the quality of the work if it’s done by an expert.

How to Maintain Jambs?

You can make window jambs last longer with proper maintenance. Things like dust, water and debris tend to accumulate every time you open a window. If these are allowed to collect and build up over time it becomes a breeding ground for bacteria and mold. This makes using the window increasingly challenging and if you keep applying brute force then it could lead to the window falling out of its frame.

Cleaning window jambs can be tricky. Below are some steps that can guide you if you decide to clean your window jambs.

  • Vacuum every jamb to clean away dirt on the window screens and the sill.
  • Make a paste of baking soda and water
  • Apply this homemade paste on the sides, top, and bottom of the jambs while keeping in mind to do the same to the corners.
  • Pour the mixture into a spray bottle and spray it up and down the jamb until the mixture bubbles.
  • Leave the mixture for five to ten minutes and clean it by wiping it with a clean cloth.
  • Using a small brush like a toothbrush, scrub the jamb from inside and outside making sure not to ignore the corners and locks.
  • Spray the mixture on areas where mold is present if relevant.
  • Apply wax or silicone to the window jambs to ensure smooth opening of your windows.

Now let’s take a closer look at jamb liners.


What are Jamb Liners?

Jamb liners fit inside jambs on the vertical sides and give an additional layer of support to keep windows in their place. They can also be placed to seal gaps and cracks and to add insulation which enhances the energy efficacy of windows.

While some jambs come with liners already fitted in, they can also be added later. They are usually made with strong, durable and lightweight materials.

It is important to measure the dimensions for the liners including jamb depth.

Jamb Extensions

Jamb extensions are placed on the interior side of the window to provide the space needed to fit the window frame. Extensions go on every side of the window.

Jamb extensions are placed on the inner side of the window to allow the space needed to fit the window frame to the window opening. Extensions can be placed on every side of the window.

They are usually added if windows are being replaced. You can also add window jamb extensions after the rest of the components have been installed.


Difference between the window jamb and sill

The jamb is the vertical part of the window frame that supports the sides of the window. The sill is the bottom part of the window frame. For windows that open vertically this part of the window holds the glass section when it is shut.

Professional Window Installers and Window Jambs

Installing jambs can be handled by homeowners with experience of basic construction and repair skills. However if you want to install jamb liners and extensions, it is advisable to get the help of window professionals.

A contractor will help you determine if or if not a window jamb needs to be replaced and get it done efficiently. It is important to be careful when working with jambs because the failure to fix them properly can result in the window being too loose or even popping out of its frame.

If you are looking to buy a property it is important to take the time to inspect window jambs. If the windows are not in good condition, jambs will betray it with signs of stains and rot. Additionally rotting and staining around a window jamb could indicate that there might be other water damage that isn’t visible such as rot due to water seeping into the window frame.

Get in touch with experts at BlackSteel

We hope this article was helpful and informative and gave you the answers you were looking for. Do you have more questions? Please visit our website to find out more about the wide range of doors and windows we offer or to speak with an expert. Feel free to call us at (855) 586 7224 to get in touch with us today! We at BlackSteel are more than happy to help you!

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What is a window jamb extension?

Window jamb extensions are placed on the inner side of the window to provide the space needed to fit the window frame. These can go on every side of the window.

How to measure window jamb depth?

To measure the window jamb depth you need to measure from where the exterior mold is attached to the window to where the interior trim of the window attaches to the window jamb.

What is a window jamb?

Window jambs are the primary vertical parts that make up the sides of the window frame.


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