Garage Door Header question

[TheCitrusMaster]

Garage doors are currently 8x7 doors. Want to convert to a single 16x7 or 17x7. In order to do that, I have to rip out this center post shown in the images.

The header is two 2x12 beams spanning 18 feet, pretty sure there is plywood between the beams. Is this sufficient to support the 18 feet span without the center post? If i do need to reinforce it, could I simply add a third 2x12 or LVL beam rather than having to build a temporary wall and removing the existing headers?

For more context, this is a single story home built in the 1960s and the roof slopes towards the garage doors, meaning the header supports the eves of the home. The garage is semi-detached, meaning its attached with a breezeway.

I don't think these two 2x4 studs would be structural but I want to get some other opinions. this project is still in the planning stages, all I have done so far is rip out some drywall.

Also is the splitting of the wood an issue here?

 

[NUTTSGT]

Looking at the color of the center post studs, they are a different color than the rest of the lumber.

That tells me, they were added later.... either there was a sagging issue and/or to switch from a single wider door to 2 smaller doors.

How long have you lived there ? Possibly talk to your neighbors and see if they remember there being a single door rather than the double doors... sometimes, a neighbor can provide information you're looking for that you can't ask a previous owner.

 

[Skooterj]

The span chart I found through a quick Google search says no. Double 2x12 span rating of 10'7". Triple, 13'2". I did a quick LVL span search, looks like you need a 3.5x14 (two 1 3/4 thick x 14 tall) to span 18'. And it looks like you have room above the current header to install a taller one. But this is a question only an actual structural engineer can answer.

 

[firebirdparts]

don't do it.

 

[BillK]

For what its worth the header above the 16 ft door in my house is a double 2x12 and has been just fine since the house was built in 1978. Same with the one in my detached garage that I built a few years later. Both of mine are on the gable ends and both roofs are truss construction so that makes a difference. Since yours are n the eave side of the garage you probably need a larger beam.

 

[PoorUB]

My dad built a garage and used 2-2x12s and plywood the span an 18 foot door, over time it sagged 2-3 inches. It was easily noticable. He eventually jacked up the center of the opening and added some steel plate and that helped. So to answer your question, no, it won't do it.

 

[rust in the eye]

Without knowing what load this bears its impossible to know. FWIW I'd build it with laminated beams.

 

[Dagny]

Looks like douglas fir so you have that going for you and no snow in Texas. But it will sag over time. There is a lot of weight on it.

 

[Innovate1]

If it was a gable end it would probably be fine but since it supports the span of the roof it needs to be bigger. To size it you need to factor in the span of the trusses or roof framing. A bigger building will need larger beam. Microlams are a good way to go for this. It's pretty straightforward to size it but there's a bit of math and looking at tables. And make sure you have enough support under the ends - probably need to add some studs.

 

[firebirdparts]

Both of mine are on the gable ends.......

Don't do this. You're confusing the guy. Totally irrelevant.

The header in your case is just for looks. His holds up the world.

 

[BobnCO]

Double Microlams; the above reference to 14” sounds right (from back when I framed a bit).

 

[abfish]

This is an easy calculation for a structural engineer. I would hire one.

 

[BobnCO]

Don't need an engineer to read the manufacturers span tables.. : )

 

[abfish]

But you need to understand the roof loading. Might need to beef up the support at the ends of the beam. I have an engineering degree, but I'd pay someone who does this everyday.

If you don't get it right, and the new beam sags the new door won't function correctly.

 

[LopezBart]

The new design requirements can be calculated from the span tables and knowing (or working backwards from the rafter span loading) the roof loading - but if you don't understand how, hire someone to do it. Also, safely replacing the existing beam is likely the more difficult and less 'by the book' part of the process.

Depending on your location, your building code requirements for wind uplift, earthquakes, etc. may have changed significantly since the 1960s. A new design would need to meet those requirements as well.

 

[Shiftless]

I don't think these two 2x4 studs would be structural but I want to get some other opinions.

Of course those studs are structural. !!
Hire an engineer and get ready to spend some serious money on your conversion to one big door to replace your 2 smaller doors. Spend the money to do it right or just get some new Sheetrock and go back to what it used to be.

 

[The Cobbler]

plywood according to load tables do not add any load factor, it's simply to build out the thickness to match the framing .

 

[Skooterj]

Of course those studs are structural. !!
Hire an engineer and get ready to spend some serious money on your conversion to one big door to replace your 2 smaller doors. Spend the money to do it right or just get some new Sheetrock and go back to what it used to be.

I don't know about serious money. A couple 16 inch, 20 foot LVL's are gonna run you around $400 with shipping. You can probably repurpose the 2x4's in the mid span to beef up the supports at the ends. And LVL's are pretty, so no need to replace the drywall.

 

[Skooterj]

Here's my question. Are those shelves staying? If so, just frame the wall to there, get a 12'??? wide door and your span is cut down considerably. You might even get away with leaving the current header as is.

 

[TheCitrusMaster]

Sorry for late reply everyone. After some research and thinking and reading these comments I've come to the conclusion that I'll definitely need some additional support for this conversion one way or another.
Im thinking my first option is replacing the 2x12s with 16" LVL. This is something I'll be doing myself, I guess I would need to make a temporary load bearing wall to replace the header.

Second option is to just add a second header behind the first one. It would reduce the space in my garage by 4" but I really wouldn't care. Benefit of this option is I don't need to remove the existing header or build a temporary wall and risk things going wrong during in the process. Anyone have any thoughts on this?

Third option I bolt on some steel plate to the existing header to increase the strength. I'm not sure how this would work out structurally compared to the other options.

Anyone have any thoughts or comments on these ideas or any other ones?

I am on the fence about a structural engineer and permits in general. Once it's covered if it's solid truly who cares. This is just a detached garage.

 

[Jeepster04]

I wouldn't hesitate to add 2 more 2x12's and call it a day. Lots of glue and structural screws.

My garage is setup how youre wanting (16' door and I dont think there is room for 2x12's. I wouldn't be surprised if mine is 2x10's and theyre also supporting brick. It does have angle iron to hold the brick but its probably screaming.

 

[Skooterj]

Adding 3 inches inside the building would also require moving the entire door track 3 inches inside the building too. Which is going to require changing the trim around the door too. With your existing header having those small cripples above, you have room for a larger header. Build a temporary wall about 2 feet inside the current wall to support the roof trusses, pull out the old header and slide the new lvl one in.

 

[jkuro]

Keep the 2-2x12 and replace the 1/2" ply with a steel flitch plate.

 

[TheCitrusMaster]

I did some looking around and I think LVLs will be easier to obtain than a suitable steel plate so I'll be going that route.

The current garage doors are very old, and so is all the trim. I planned on replacing it all regardless. Also since I am installing a new garage door, removing the tracks is also a non-issue. Because of this I am still stuck between options 1 and 2; replacing the 2x12s with LVL or adding new LVL behind the 2x12s without removing them.

The main benefits I see to keeping the 2x12 and installing a second header behind them is that I don't need to build a temporary wall and risk things falling while removing the old headers. Can anyone give me a good reason why I actually need to remove the old header vs just installing a secondary header?

 

[Skooterj]

Keep the 2-2x12 and replace the 1/2" ply with a steel flitch plate.

Plate that size is going to be at least a thousand dollars and not super readily available. Not to mention too heavy to lift manually.
Main reason to replace the header is you keep 3 inches of garage space and most premade trim will fit.

 

[JohnX14]

Adding 3 inches inside the building would also require moving the entire door track 3 inches inside the building too. Which is going to require changing the trim around the door too. With your existing header having those small cripples above, you have room for a larger header. Build a temporary wall about 2 feet inside the current wall to support the roof trusses, pull out the old header and slide the new lvl one in.

This is what I would do. Spot on.

 

[jkuro]

Plate that size is going to be at least a thousand dollars and not super readily available. Not to mention too heavy to lift manually.
Main reason to replace the header is you keep 3 inches of garage space and most premade trim will fit.

I have done this many times years ago. I did not know steel prices were that high today. The other choices are a steel I beam or an LVL.