Everything You Need to Know: Window Balances

A Definitive Guide to Window Balances

Everything you need to know window balances

Window balances are pieces of hardware used to regulate the opening and closing of the window sash. All hung windows use them in some capacity but few homeowners consider how their windows operate until a window takes too much effort to close, or slams closed suddenly. These are both good indicators that the window balances are due to be replaced. Most homeowners assume that they are going to have to replace their windows, which is not true in most cases.

Trying to fix a broken window balance system can be frustrating for someone with no experience in the window industry. The goal of this guide is to walk through the types of balance systems and what is needed to replace them.

We always suggest replacing both assemblies at the same time. Repairing one side can cause the older balance to break under the additional stress of keeping up with the new balance or the new balance to break prematurely while trying to support most of the weight of the window.

The first step is to remove an undamaged balance from the window to compare to the available replacement options. This process depends on the type of balance you have. Below are the common balance styles found in residential windows.

Andersen balances
Andersen balances
Rod balances
Rod balances
Channel balances
Channel balances
Coil balances
Coil balances
Hybrid balances
Hybrid balances
Spiral balances
Spiral balances


Some, but not all, Andersen windows use a type of box-style overhead balance. These are easy to identify once they’re uninstalled, but it does take a fair amount of effort to remove them from the window header.

Once the balance is removed, all that’s left to do is locate the stamp numbers. Usually, there will be multiple stamps on the assembly but the one that identifies the balance will include either a # symbol, H, or P. It can be found in one of the locations indicated in the example below.

Andersen balance stamp
Andersen balance stamp

Once you have your number, you can match it up to the corresponding SWISCO product code or reach out the experts for help.

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Rod balances are an outdated style of balance that can be replaced with a better-quality channel balance. See our full conversion video that will walk you through the process step-by-step.


Also known as block-and-tackle balances, channel balances contain a spring and pulley system within a metal channel. They usually feature a unique combination of fittings or attachments at either or both ends. The spring mechanism is carefully calibrated to support the weight of a window.

How to measure channel balance length
Non-Tilt Channel Balances
How to measure channel balance length
Tilt Channel Balances


You can remove channel balances from a non-tilt window by watching the video below or by following the written instructions in SWISCO’s channel balance removal guide.

Once you’ve removed the balance, locate the strength code on the metal channel. Unfortunately, this code doesn't identify your balance — just the spring strength needed to support the weight of your window.

For example, if your stamp is “28 3” or “28 C”, you’d choose the strength option “2830” to support a window weighing between 16 lbs. and 23 lbs for some standard balance series.

Channel balance stamp Channel balance stamp

If there is no visible stamp, check another balance from an identical window. If you still can’t locate a stamp on any of your balance channels, you can remove the window sash and place it on a bathroom scale, or step on the scale while holding the sash and subtract your weight.

Using the weight of your sash, review the weight ranges associated with each “stamp option” once you’ve identified the correct balance series.

You’ll have to confirm a few dimensions to narrow down your replacement options. Measure the length of the metal channel, not including the end fittings, as well as the width of the channel.

How to measure channel balance length
Channel length
How to measure channel balance width
Channel width

Now that you know the stamp and the channel size, you’ll need to compare the style and depth of your balance fittings to the options in our catalog.

Channel balance fitting depth
Channel balance fitting depth

These pieces help to keep the balance snug in the track and against the sash. Getting something even 1/32” off can make a difference.

Channel balance wingless fitting
Channel balance winged fitting

You can find a more comprehensive overview of these fittings and their differences in the Classifying Channel Balance Fittings guide.

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For a tilt window channel balance, you’ll need to determine if the balance channel has a ribbed or straight, plain-style channel.

Plain channel balance
Plain Channel
Ribbed channel balance
Ribbed Channel

Next, you’ll compare your balance fitting to the options in the plain or ribbed channel sections in the SWISCO catalog.

Remember to check the integrity of the parts that work with your channel balances such as the take-out clips and top sash guides for non-tilt windows; as well as the pivot bars, pivot shoes, and tilt latches for tilt-windows.

As always, make sure to contact the experts with a photo of any part that you’re unable to locate a replacement for.

Shop for channel balances here


A coil balance sometimes referred to as a spring or constant force balance, is a type of sash support that uses coil springs anchored to a pivot shoe to enable the window to stay open. Remove your coil balances by following the videos below or the written instructions in our coil balance guide.

When removing your coil balance, take note of any stamp numbers. Oftentimes, they are found imprinted on the tongue of the metal spring, cartridge, or coil casing. If you don’t see one, weigh the window and divide the weight by the number of coils in your window.

Coil balance stamp
Coil balance stamp example

Since most coils tend to look very similar, your search for the correct coil will rely heavily on the pivot shoe or coil cartridge. Each series of coil spring is designed to work with a specific pivot shoe, so if you can identify yours, the compatible coil series will follow. Compare your style and dimensions to our selection.

Other times, the assembly is part of a complete housing unit that comes with a housing, coils, and cover.

When replacing your coils, check over the surrounding hardware like the bushing, coil housing, pivot shoes, and pivot bars to make sure you have all the necessary parts to repair the window.

Shop for coil balances here


Spiral balances are spring mechanisms that are distinguished from other balances by their use of a hand-wound spiral rod that extends from a housing tube. This rod applies tension to the spring, which allows it to keep the sash up when raised. If you have a window that tilts in for cleaning, you can follow our video to remove the spiral balance from the window.

Next, you’ll need to measure the length and diameter of the tube that houses the spiral. The 3/8″ diameter Series 900 Spiral Balance and 9/16” (considered 5/8" in the trade) Series 600 Spiral Balance are common replacements for balances that have two pins at the base of the spiral to anchor the assembly to the pivot shoe.

How to measure spiral balance length
Spiral balance length

You’ll also need to choose the tip color on the balance product page that matches your original hardware. If the tip is missing or faded, you’ll need to weigh the sash and choose the appropriate weight range.

Make sure to check the integrity of the pivot shoe that the spiral anchors to. If the shoes need to be replaced as well, compare the style, width, and thickness of our replacement options.

Replacing spiral balances for non-tilt windows can be a much trickier process compared to newer tilt windows. They are a dying breed but still turn up in older homes. To remove yours, follow our detailed guide to compare your balance length, diameter, and spiral tip to our selection of replacement options. Keep in mind that these balances anchor to a bracket screwed to the bottom or side of the sash.

If you don’t see what you’re looking for, reach out to us SWISCO’s team of experts for assistance.

Shop for spiral balances here

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