Our LiftMaster 1300, installed in 2011, recently has a situation that it sometimes does not open --- when attempting to open the door either with remote or the power switch, the motor starts humming but the door is not moving. When that happens, we have to pull the Emergency Release Handle to loose it, then a subsequent power on (remote or switch) will make it open. Also, this is not happening all the time. Sometimes it opens normally. What's the potential cause and what can I do to fix this?

I have a pole barn that is in need of some TLC ( tender loving care). My first obstacle is that I wish to raise the roof of the pole barn by 3 feet to accommodate two new 10 ft high garage doors. The poles are in good shape look almost brand new. The construction is 8 foot on center poles, truss support, trusses 4ft on center. MY first thought was to leave the truss support (header) in place and simple build 3 feet up from that place a new truss support, place the trusses and that would add my additional height that I wanted. Although I am looking for better ideas, of course I want to do it correctly, and I will have it inspected. Anyone with any thoughts, I really appreciate the input.