Short answer
A sash that drops down on its own has a broken balance, not a bad window. Raise it a few inches and let go. If it slides down on one side and the frame is square with no cracked glass, the pivot shoe and the coil balance on that side have failed, and both are cheap parts fitted from inside the room. If the sash also grinds or jams as it moves, the frame is out of square and the window itself is the problem.
Tell a broken balance from a bad window in two minutes
- Raise the lower sash 6 inches and let go. A good sash stays put. One that slides, drifts or slams down has lost its balance tension.
- Watch which side drops first. One corner falling while the other holds points at a single broken balance.
- Lower the sash and look into the bottom corners of the track. The pivot shoe is a small plastic block that the sash pin sits in. A cracked, split or empty shoe is the failed part.
- Look for the coil balance behind the shoe. It is a curled metal ribbon in the track. If it hangs loose, is unwound or has popped off its hook, it is not holding anything.
- Push the sash up and down slowly and listen. Smooth travel means the frame is fine. Grinding, scraping or a hard spot on one side means the frame has moved.
- Try the other windows of the same age on the same wall. Two or three doing this at once is normal wear on the original balances.
If the sash drops and the shoe or coil is broken, it is a balance repair and the window stays in the wall. If the sash binds hard, the glass is cracked or the frame is out of square, the window itself is the problem.
Repair or replace
| Situation | What to do |
|---|---|
| Sash drops on one side, frame square and glass fine | Repair. Fit a new pivot shoe and coil balance, and do the matching side at the same time. |
| Sash drops on both sides | Repair. Replace both balances. They wear at the same rate and one new part makes the sash hang crooked. |
| Pivot shoe has never held since the window was installed | Repair. The shoe is the wrong size or was never seated. A window person swaps it for the right part. |
| Top sash dropped down and is now jammed in the track | Repair. The sash came off its balance and is binding. It has to come out before anything is adjusted. |
| Sash drops and the glass is cracked or fogged between panes | Replace the sash. You are paying for glass and hardware anyway, so get both at once. |
| Sash drops and the frame is out of square or the vinyl is cracked | Replace the window. Balances cannot hold a sash the frame no longer guides. |
| Window is 20 or more years old and the balance part is discontinued | Replace the window. Hunting a dead part costs more than the unit. |
What it costs
Runhome contractor estimates for a window whose sash will not stay up ran from $195 to $495 to replace the balance and pivot shoe, and from $475 to $1,200 to replace the whole window, as of October 2026, including the trip and assessment.
| Option | Range |
|---|---|
| Repair, new pivot shoe and coil balance | $195 to $495 |
| Full window replacement, unit plus labour | $475 to $1,200 |
Can I do it myself?
Yes, on a ground-floor vinyl double-hung if the sash still tilts in on its latches. Tilt the sash in, lift it off the pins, pop the old shoe and coil out of the track with a screwdriver, take the broken part to a window supplier to match it, then reverse the steps. Budget an hour and have a second person hold the sash, because the glass carries most of the weight.
Hire someone if the window is above the ground floor, over a stairwell or over a sink you cannot stand beside. A sash with no tension can drop the full height of the opening and break on the way down. Hire for a wood window with ropes and hidden weights, for a sash that is already jammed in the track, and for any window you cannot reach with both hands free. Never prop a dropping sash with a stick or a bottle and call it fixed, especially in a room a child uses.
What a contractor will ask you
Have these ready and you skip the back-and-forth.
- Which sash moves, the top or the bottom one, and whether it drops, jams or both.
- When it started. Say so if it has never worked right, because that points at the wrong part being fitted.
- Whether the sash feels loose and drops on its own, or is stiff and hard to move.
- Whether the other side of the same sash holds its position when you let go.
- Whether the coil behind the pivot shoe is still attached at both ends, or looks popped out of place.
- Whether the sash tilts inward normally on its latches, or one side lets go when you tilt it.
- The window material and rough age, and the brand if there is a label on the sash edge or in the track.
- How many windows in the house do the same thing.
- A wide photo of the whole sash and frame, showing the track from top to bottom, not just the broken piece.
Common questions
- Why does my window slam shut on its own?
The balance has lost all its tension, so nothing holds the sash's weight. Nothing you can adjust will bring the tension back. The shoe and coil get replaced as a pair.
- Do I have to replace the whole window if the balance is broken?
No. The balance, the pivot shoe and the clips are serviceable parts, and they cost a few dollars each. The window only goes if the frame is out of square or the glass has failed.
- Can the balance be replaced without taking the window out of the wall?
Yes. The work happens from inside the room, through the opening, once the sash is tilted in and lifted off its pins. The frame, trim and exterior stay untouched.
- The top sash dropped down and now it is stuck. Is that the same problem?
Usually, yes. The top sash lost its balance, slid down and wedged in the track, and a jammed sash often binds harder on one side. Leave it where it is, because forcing a stuck sash cracks the glass.
- Is a window that will not stay open a safety problem?
Yes, if it is above the ground floor or in a child's room. A sash with no tension can fall shut on hands or drop out of the frame when tilted. Keep it closed and latched until it is fixed.