What is an effective counterbalance for roll-up garage doors?

Extension springs serve as an effective counterbalance for roll-up garage doors due to their ability to store and release energy. When the door is lifted, the extension springs stretch, storing potential energy that helps support the weight of the door. When the door is lowered, the springs contract, releasing that stored energy and assisting in the lowering process. This mechanism allows for smooth operation and reduces the effort needed to open and close the door by counteracting its weight.

Other counterbalance mechanisms, such as gravity weights or pulleys, might be used in different applications but are not typically associated with roll-up garage doors. Gravity weights would require additional structural support and space, making them less practical. Pulleys can assist in lifting, but they don't inherently counterbalance the door's weight in the same manner as extension springs. Cord systems may provide a means to operate the door, but they do not offer the same level of balance and support provided by extension springs.