Door weight is important when trying to figure out what torsion or extension springs are needed to counterbalance the door.
How much wight garage door.
A standard 25 steel gauge 8 x 7 residential garage door from unique raynor amarr haas.
It should be noted that since the cable loops around a pulley the lifting force of a 210 pound spring is only 105 pounds as seen by the garage door.
Therefore you need a pair of 210 pound springs even though your total door weight is 210 pounds.
How much weight can a garage door opener lift.
Based on this rating a 1 2 hp opener be able to lift about 185 pounds and a 3 4 hp opener should be able to lift over 370 pounds.
If you have a heavier door that weighs more than 150 pounds with one spring still wound you will need to use 2 scales and position them under the first row of hinges from each end of the garage door.