Sash Window Add-On Weights
2 products
2 products
Double-hung sash windows rely on only a few key components to function properly — and one of the most important is the counterweight.
Each moveable sash (pane of glass) in a double-hung window is connected to a hidden weight inside the window frame. A sash cord runs over a pulley at the top of the frame, connecting the sash to this weight. The counterweight balances the sash, allowing it to move smoothly and stay in place when opened.
Anyone in the window restoration trade knows that rebalancing is an essential part of servicing sash windows. Most often, problems with sticky, stiff, or dropping windows are due to incorrect weight distribution.
Over time, windows may be reglazed with heavier glass — for example, replacing old 2mm glass with 3mm glass — adding extra weight to the sash. If the counterweights haven’t been adjusted, the window can become unbalanced and potentially dangerous.
Incorrectly balanced windows:
Most rebalancing jobs require adding weight, not removing it. That's where add-on weights come in — small supplementary weights that fine-tune the balance of your sash.
Unlike most add-on weights on the market (which are square), our weights are round and domed. Why? Because original sash weights are round, and inserting square weights can cause friction issues inside the sash box.
Our smart design allows the add-on weights to fit seamlessly onto existing round weights, ensuring smooth movement and easy installation. Available in:
Whether you're restoring a heritage window or upgrading modern timber joinery, our round add-on sash weights make rebalancing faster, safer, and smoother.