What are Window Weights?
Window weights are lead weights that counterbalance the weight of a window sash – the movable part of the window – in older houses. They are common in double-hung windows, in which the two sashes move in independent tracks; the top one can be lowered and the bottom one raised, which allows circular airflow, hot air out the top and cooler air in through the bottom. Because older windows are made of heavy materials, raising a window can be difficult, and without counterbalance, the sash can come crashing down, potentially causing the panes to break. The solution is a pulley at the top of the window casement, with a cord attached to the sash, and inside the window frame itself, window weights that are sized to exactly or nearly equal the weight of the window sash. There are two window weights per sash, one on each side of the window. The ‘sash cord’ is the rope that connects the window sash to the window weights. Over time, these ropes can wear out and sometimes break, causing the window
