You raise the bottom sash, let go, and it slides back down. Or it creeps down an inch at a time over an afternoon. Or worse, it drops hard the moment your hand leaves it. A sash that will not hold its position is more than an annoyance. A falling sash can pinch fingers or land on a small child leaning on the sill, so treat it as a safety problem first and a repair second.
What holds a window open in the first place
A double-hung or single-hung sash is heavy. Glass alone weighs a lot, and insulated units have two panes. What lets you lift it with one hand and leave it anywhere along the way is the balance system hidden in the side jambs. The balances push up with roughly the same force that gravity pulls down, so the sash floats.
There are a few common designs:
- older wood windows hang iron or lead weights on cords inside pockets in the wall
- a spiral balance is a twisted rod inside a tube, common on older aluminum and builder-grade windows
- a block-and-tackle balance runs a cord from a spring over small pulleys
- a constant-force coil balance uses a flat coiled spring that unrolls as the sash moves
Each type uses stored tension. When a cord breaks, a spring weakens, or the sash loses its connection to the balance, the window stops holding position.
Common reasons a sash drops
The sash came loose from the balance
On tilt-in windows, the bottom corners of the sash ride on pivot pins that sit in a part called a balance shoe. If the sash is slammed shut or tilted carelessly, the pivot can pop out of the shoe. The balance stays where it is and the sash has nothing holding it up.
The balance has worn out or broken
Springs lose tension over years of use, and cords fray. On older aluminum windows the spiral balances often give out one side at a time, so the sash tilts and drags as well as falling.
The sash cord snapped
In older central neighborhoods like Hyde Park or Travis Heights, original wood windows sometimes still have weights and cords. When a cord breaks, the weight drops into the wall pocket and that side of the sash has no counterbalance.
Something is fighting the sash
Less often, the problem is friction. Paint on the tracks, a swollen wood sash, or a frame pushed out of square by foundation movement can make a window bind in some spots and slip in others.
Early signs a balance is giving out
Balances rarely fail all at once. Watch for a sash that needs more effort to lift than it used to, one that drifts down slowly when you leave it at half height, or one side that rises ahead of the other so the sash racks in the frame. A grinding or snapping sound inside the jamb as the window moves is another clue. Catching it at this stage makes the repair simpler and keeps a heavy sash from dropping unexpectedly.
In Austin, many people only discover the problem in fall, when the weather turns and they open windows that have stayed shut since May. If a sash misbehaves on that first try, stop and close it rather than working it up and down to loosen it.
What you can safely check
A few checks need no tools and do not involve the balance at all:
- Look at both top corners of the bottom sash. Are both tilt latches fully extended into the frame? A latch that is pulled in lets one side of the sash sit loose.
- Look down into the track on each side. Is anything stuck there?
- Is the sash sitting square, or is one side higher than the other?
- Does the problem happen at every height, or only near the top or bottom of travel?
Write down what you find. It helps whoever comes to fix it.
Why we do not recommend resetting balances yourself
There are plenty of online videos showing how to reseat a sash on its balance shoes or swap a spring. On paper it looks quick. In practice, balance shoes and springs hold real tension, and a shoe that releases while you are working can snap up the track. Sashes are heavy and awkward when tilted out. Parts differ by manufacturer and by the weight of the sash, so a generic replacement from a hardware store may not match. And on a newer window, taking the sash out yourself can complicate a warranty claim for something the manufacturer would have fixed.
For windows that are still under warranty, the best move is to call the installer or the manufacturer’s service line. For older windows, a window repair professional can match the right balance to the sash weight.
What to do until it is fixed
- Keep the window closed and locked.
- If you must open it, do not leave it unsupported. Prop it with a cut piece of wood that rests on the sill, and remove the prop before you close it.
- Keep children and pets away from that window.
- Do not lean on the sill or reach through the opening.
What to have ready when you call
Find the label or serial number on the window, which is often on the frame or the glass spacer. Note which sash is dropping, whether it happens on one side or both, and roughly when it started. If you have the original paperwork from installation, keep it nearby. With that information, the service team can often bring the right parts on the first visit.
When it makes sense to replace
A single worn balance on a sound window is a repair. A house full of old aluminum windows where the balances are going one after another is a different situation, especially if the glass is single-pane and the west-side rooms bake every summer. The same goes for wood windows where several cords are gone and the sashes are swollen or rotten. Modern single-hung and double-hung windows use balances designed to be serviced, and installation includes setting each sash so it moves and holds the way it should.
If you have one window that will not stay up or a whole house of them, anywhere in the Austin area, call The Window Source of Austin at (512) 524-9455. We offer a free in-home estimate, and we can tell you whether repair or replacement makes more sense.