Guest post by Mark Fisher
I am not a home inspector, but our paths cross daily and I want to help you, so you can help us, and we both help the end consumer.
A little background: I am an industry ( IDEA) certified garage door master technician, certified instructor, certified trainer, 27 years on the job, and International Door Association Technician of the Year 2020.
My main area is residential doors , but I do frequent commercial doors as well. Then there’s the blurry gray area of residential doors adapted from commercial lines.
So there’s a few misunderstandings about some of the ways inspectors test doors. This mainly concerns obstruction testing and what the requirements are for safety eyes.
First the eyes: Local codes notwithstanding, there isn’t any blanket or standard code that says safety eyes must be specifically right at 6”. UL325 states safety eyes are to be, to manufacturer’s specs. Most manufacturers, and all who are in DASMA agree that 6” is the maximum height, but not any specific range or height under that.
Liftmaster’s specs say “No greater than 6”. That means eyes at 2”, 3”, 4”, or 1” are in fact, up to specs. Genie says between 4”-6”, so 4” is good but 3” would be out of compliance. Marantec specified 3”-5” from the floor is good.
As new models come out, they sometimes update/ change those specs. They stay at the 6” max, but the specific range may change among the various manufacturers.
Also, in the event that the eyes are damaged, blocked or missing- if you have to hold constant pressure on the wall button to close the door, and maintain that pressure until the door is fully closed to keep the door from reversing- then the operator is actually functioning correctly. Constant pressure to close is the only allowable alternative to not having eyes since 1992. Annoying for sure, but in compliance.
Holding your arm out and expecting the door to reverse is not a thing. No manufacturer goes by this. Doors have a 15lb to 25lb of resistance range. Depending on the type of door, weight, and track set up, the door will have areas of greater and lesser resistance going through the radius of the track. The motors are set to push through those areas and holding an arm outstretched does not meet, much less exceed that resistance. The only universally recognized manufacturer test is a 1”x1.5” block of wood (not a roll of paper towels). A door closing on a 1.5” block of wood must reverse. A door closing on a 1” block of wood must stop. Use a piece of 5/4 board and it could go either way.
Now here’s where things get interesting. Openers have moved away from mechanical set screws. Now almost all of the openers currently produced have electronic forces and travel limits. These openers actively monitor the amount of force needed to open or close a door and will adjust as needed (within a pre-set amount of parameters). Slight changes due to expansion and contraction, seasonal temperatures, humidity, etc… the motor will adjust. Sudden or large changes (hitting obstruction/ broken spring/ lack of maintenance) will trip the excessive force settings.
Now the caveat to the block test: since the opener monitors the force needed, if you close the door on the block repeatedly, without running a clear cycle between hitting the block, the door will learn to push past that spot. You must remove the block, run the door at least once (2-3 times is better) then you can put the block back again.
Now, I know a lot of door guys give home inspectors the stink eye, but I am not one of them. You are the guys who keep us in check and weed out the hack jobs. I fully respect that. The end goal is to protect the homeowner from potential injury or death.
One last thing: as a result of a patent infringement lawsuit, the current generation of Liftmaster and Chamberlain openers no longer flash the main work light when safety eyes are obstructed. Instead, the door just reverses and will give an error code on a LED light at the power head or an error code number on the digital wall control if that model has one. If it reverses due to excessive force, upon reaching full open, the work light flashes and motor beeps. Crossing the beams of an open door will no longer turn on the work light.
And as is the case with any products, competition among the manufacturers means newer models with more innovative features. This means designs change, features are added, removed, or modified. The opener you test today is not like the one tested 10 years ago, and most assuredly will not be like the one you test 2 years from now.
So, I would like to invite you to present any questions as they pertain to garage doors and I’d be happy to answer or assist in any way I can.
Mark Fisher is an industry expert with garage doors. He started with Crawford Door Systems Inc (not affiliated with any other Crawford) of Wilmington, NC in 1995 as a commercial technician. After 7 years, he switched to the residential side of the company, but still frequently installs commercial doors, residential styles on commercial applications, or commercial door setups in residential Accreditation.
He is a supervisor, QC, builder liaison, and garage door trainer. He is an Institute for Door dealer Education and Accreditation ( IDEA) certified Master technician – which means certified in residential, commercial sectional, rolling steel ( coil up) and rolling steel fire doors- certified trainer and instructor, International Door Association ( IDA) Tech of the Year for 2020, and EPA lead Abatement certified. I occasionally assist on both IDA committees and assist with webinar training events for IDA/ IDEA. You can reach Mark with any questions at firstname.lastname@example.org