When shopping for double- and single-hung windows, homeowners should be cognizant of the windows’ balance system. A poor choice in hardware—particularly the balancing system—could mean long-term product dissatisfaction, so it’s important to get the best system available.

First off, what does the balancing system do? It basically is the hardware (usually not visible) used to open and close single- or double-hung windows—so, the type of balancing system can have an effect on the operation of the window.

There are basically three types of window balancing systems—spiral, block & tackle, and constant force. After examining and operating windows that use each of these three systems, window industry professionals generally agree that there’s no contest—the constant force balancing is the hands-down winner. “Constant force” means that, unlike other balance systems, the effort to open and close the window sash is constant. It’s the same at all points of opening and closing. Operation of windows with constant force balancing is virtually effortless, silent, and unbelievably smooth. Constant force balance systems are also more dependable. Because there is only one moving component, the balance spring, operational issues are extremely rare. These systems are typically tested to 10,000 or more cycles and still open and close smoothly. They also last longer than other balance systems because the spring is inside an encapsulated unit. This means that the most important part of the system isn’t exposed to dust and dirt over time.

Block and tackle and spiral balances both have multiple moving parts—which results in many more components that are prone to fail over time. Block and tackle balances consist of a pulley system and cord. The cord wears down as the window is operated and eventually frays or breaks. Spiral balances feature a spiral-shaped steel rod that’s connected to a torsion spring. Not only are spiral balances noisy when operated, but the way they operate also generates excessive friction—which results in wearing surfaces and, eventually, failure to operate correctly. Both systems, although not usually very visible, do attract and collect dirt. Over time, this affects the performance of these balance systems.

Before purchasing windows, homeowners should thoroughly research the products they’re considering—including what type of balance system is used and what type of warranty that hardware carries.