Garage Doors, Jackshafts and ceiling clearances

[shammatt]

I'm about to tear down my existing attached 2 car garage and replace with a 34' x 65' garage/shop with 600 sqft upstairs room for wife's crafts. My problem relates to minimizing the overall height (visual impact) of the building while still providing room inside the garage for car trailer storage. Dimensions are: trailer height 117", minimum garage door height (smaller single wide door) to be 120" (10'). Planning to use jackshaft door openers.
Question now is, how high must the ceiling (floor of the upstairs craft room) be to allow for the door tracks? I'm trying to find someway to minimize the difference between the garage door height and the interior ceiling height.
Any suggestions?
Thanks, Steve Hammatt
Mount Vernon, WA

 

[lynnbilodeau]

There is a one foot differential on mine.
There are pics on the last thread I started (about door openers).

 

[gnpenning]

The most common sizes doors can be purchased with are 8",10",12",15" Radius track, plus high lift and follow the roof line, etc. Other radius's are available but these are the most common. The door panel will come 2" above the track and needs to be accounted for in your height.

The more radius you have on the track the smoother the door will open and the less stress you put on hinges, rollers, panels, etc. Jackshaft openers where designed for high lift types of tracks. While many use them with tracks with smaller radius they should then have pusher springs as per Liftmaster. Results very on this.

Your garage door is the biggest and heaviest moving thing you most likely will have and for some reason is an after thought for most. Good of you to look ahead. For my own house I put in 15" radius for 8' high doors which have 24" headroom (10' ceiling height). I could have went with a 18" track but it was a an overkill for my purpose. My next shop will have 2- 14' doors and will be going with 18" tracks I will have 24" headroom (16' ceiling height) I will be putting in 3" doors.

 

[matt_i]

My guess is you will have at minimum a 11-7/8" LVL or 2x12 header over the door (depending on single- or double- width), possibly could go larger unless the room is built into attic trusses.

Might be easier from a heating and cooling standpoint to go bigger (if possible) and just build the footage all on one floor.

 

[wssix99]

Are you going to install the doors yourself? You have some choices....

From the top of the door, you'll have the radius of the track, plus the headroom. (The door will stick above the track a bit, the torsion spring will typically be above the top of the tracks also, and you may have lighting fixtures sticking down that will interfere with the light.)

If you really want to pack things in tight, you can use a low headroom torsion spring package, but some of those may limit the type of openers you can use. Likewise, you'll have increased maintenance of the door, as noted above.

I'd suggest taking the time to pick out the door/tracks now, and then spec the building around that. -> Don't forget to allow for the slope of your garage floor, which will shorten your floor-to-ceiling height as you move in to the room!

 

[DougWil]

I bought and installed a Wayne Dalton low headroom door and track only to find that the door in the open position is well below the bottom of the door header.

Think I lost about 4-6" of headroom rolling something through the open door.

 

[shammatt]

Lot's of good information here. I thank everyone. My local garage door vendor came out yesterday but wasn't very encouraging nor willing to look at options. I'll be going into the
"big city" soon and have a visit with another vendor to see if he also has some suggestions. Thanks again.

 

[pmiranda]

The rule of thumb is to add 1 foot to the door height to get the ceiling height. Of course, it only needs to be that high for as far into the garage as the door goes, so you could drop the ceiling under the hobby area. How long is the trailer? I'm guessing you're putting the overhead door(s) on the short side of the building?
I'm thinking that you could do scissor trusses for the back 20' of the building to give you two stories in the minimum roof height, and still have attic trusses in the front 45' with plenty of height for the garage door to clear a 40' trailer.
To keep the math simple, say 8' under the 30x20 hobby space, 7' min height in the hobby space, 1' between floors, 1' of lost height to the scissor truss and a 4/12 pitch roof, you're looking at
8+7+1' - 2'*4/12 ~= 17' side wall height
17' + 1' + 17*4/12 ~= 23' peak height

Basically, having enough height to go two stories in part of the building leaves plenty of height for your trailer in the other part.