Flat screwdriver
Use it for: To remove take-out clips, pry trim carefully, or help release the balance.
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How to Replace a Window Sash Balance
If your hung window drops shut, will not stay open, or feels loose on one side, replacing the window sash balance is often the right fix.
This repair is usually manageable for a careful homeowner, but the replacement has to match the old balance closely. Take the old part out first if needed so you can match the type, length, and markings before installing the new one.
Before you start: Match the balance type, length, strength stamp, and window compatibility before ordering.
Safety first
- Support the sash with both hands during removal and reinstallation so it does not drop suddenly.
- Wear gloves because balance hardware and window track edges can be sharp.
- Keep fingers clear of spring-loaded parts when disconnecting or reconnecting the balance.
- Use a stable step stool if you need extra height to reach the upper track.
Tools you may need
Phillips screwdriver
Use it for: To remove and reinstall screws that hold the balance or sash hardware.
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Needle nose pliers
Use it for: To grab clips, guide the balance, and control small metal parts.
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Tape measure
Use it for: To measure the old balance length so the replacement matches.
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Work gloves
Use it for: To protect your hands from sharp metal edges and broken glass.
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Step stool
Use it for: To reach the upper sash track safely on taller windows.
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Step-by-step fix
Step 1: Make sure the sash balance is really the problem
- Open the window a few inches and let go carefully while supporting the sash with your hand.
- Watch for the sash dropping, tilting unevenly, or feeling much heavier on one side.
- Check both side tracks for a broken, loose, or missing balance, loose take-out clips, or a disconnected shoe or pivot point.
- If the window is painted shut, badly swollen, or rubbing hard in the frame, fix that binding issue before replacing parts.
If it works: You have signs that the sash balance is worn, broken, disconnected, or missing.
If it doesn’t: If the window stays in place and moves evenly, the problem may be dirty tracks, binding, or another sash hardware issue instead.
Stop if:
- The glass is cracked or loose in the sash.
- The frame or sash is rotted, badly warped, or pulling apart.
- The window is unstable enough that the sash could fall during removal.
Step 2: Set up the window and remove the sash
- Put on gloves and clear the area below the window.
- Unlock the window and raise the lower sash a few inches.
- Look for the sash release method used on your window, such as tilt latches or take-out clips in the side tracks.
- Support the sash with both hands as you tilt or lift it free so it does not twist and damage the frame.
- Set the sash on a stable surface where the glass is protected.
If it works: The sash is out and you can reach the balance hardware in the side track.
If it doesn’t: If the sash will not release, look again for hidden take-out clips, tilt latches, or screws holding the balance in place.
Stop if:
- You have to force the sash hard enough that the glass or frame may crack.
- A spring-loaded part is under heavy tension and you cannot control it safely.
Step 3: Remove the old balance and match the replacement
- Take a photo of the old balance before removing it so you can copy the orientation later.
- Remove any screws or clips holding the old balance in the track.
- Lower the balance carefully and disconnect it from the shoe, pivot bar, or sash attachment point.
- Measure the metal or body length of the old balance and note any stamped numbers or weight markings.
- Compare the old and new parts side by side and make sure the type, length, end fittings, and connection points match.
If it works: The old balance is out and the new one matches the original closely enough to install.
If it doesn’t: If the new part does not match, use the old balance and its markings to order the correct replacement before continuing.
Stop if:
- The balance channel or track is bent badly enough that the new part will not sit straight.
- The replacement type is clearly different from the original and would require guesswork to install.
Step 4: Install the new sash balance
- Place the new balance into the same side track and in the same orientation as the old one.
- Reconnect the lower end or attachment point to the shoe, pivot bar, or sash connection.
- Reinstall any screws or retaining clips without overtightening them.
- If your window uses a balance on both sides, replace the other side as well so the sash lifts evenly.
- Move the balance or shoe by hand as needed to line it up with the sash mounting points.
If it works: The new balance is secured in the track and lines up with the sash hardware.
If it doesn’t: If the balance will not line up or seat fully, remove it and compare the end fittings and orientation to the old part again.
Stop if:
- The track is damaged enough that the balance cannot be secured.
- The balance binds immediately because the shoe, pivot bar, or track is broken.
Step 5: Reinstall the sash and reconnect it to the balances
- Lift the sash back into position and reconnect each side evenly.
- Tilt or lower the sash back into the frame, depending on your window style.
- Make sure both sides are seated in their tracks before letting go.
- Close the window fully, then open it again slowly to feel for smooth movement.
- Lock and unlock the window once to confirm the sash is sitting square in the frame.
If it works: The sash is back in place and moves through the track without twisting or scraping badly.
If it doesn’t: If the sash sits crooked or one side lags behind, remove it again and check that both balances are attached at the same height and fully engaged.
Stop if:
- The sash will not seat in the frame securely.
- The sash can slip out of the track or drop unexpectedly.
Step 6: Test that the repair holds in normal use
- Open the window to several positions, including a few inches, halfway, and near the top.
- Let go carefully each time and confirm the sash stays where you leave it.
- Close and reopen the window a few times to make sure the movement stays smooth and even.
- Listen for scraping, popping, or spring noise that suggests the balance is misaligned.
- Check again after a day or two of normal use if the window was hard to move before the repair.
If it works: The window opens smoothly, stays open on its own, and closes without one side dropping.
If it doesn’t: If the sash still slides down or feels uneven, recheck the balance match, attachment points, and whether both sides should have been replaced together.
Stop if:
- The sash still will not stay open after correct installation.
- The window frame, track, or sash shows hidden damage that is causing the balance to fail again.
Replacement Parts
Find a window sash balance on Amazon
Match the balance type, length, strength stamp, and window compatibility before ordering.
As an Amazon Associate I earn from qualifying purchases. Repair Riot may earn a commission at no extra cost to you.
Verify the repair
- The sash stays open at more than one height without drifting down.
- The window moves evenly without one side lagging or dropping.
- The sash locks and unlocks normally after reinstallation.
- There is no obvious scraping, popping, or loose hardware in the side tracks.
FAQ
Do I need to replace both sash balances at the same time?
Usually yes if the window uses a balance on both sides. When one fails, the other is often worn too, and replacing both helps the sash lift evenly and stay level.
How do I know which replacement balance to buy?
Match the balance type, overall length, end fittings, and any stamped weight or strength marking on the old part. Taking the old balance out first is often the safest way to avoid ordering the wrong one.
Can I use a balance that is close in size?
No. A balance that is the wrong type, length, or strength can make the sash hard to move, unable to stay open, or unsafe to operate.
Why does my window still slide down after I replaced the balance?
The new part may be the wrong match, installed backward, not fully connected, or only one side may have been replaced. A damaged shoe, pivot bar, sash, or track can also cause the same symptom.
Is this repair the same on every window?
No. Hung and tilt windows use a few different balance styles and release methods. The basic idea is similar, but the exact removal and attachment points can vary by window design.