Any building/framing/structural gurus here?

[the spindoctor]

at some point a previous owner enclosed the garage and i'm getting ready to switch it back. it originally had two 8' doors with a 1' center post, and has two 2x12's spanning the entire 17 1/2' distance sitting on two vertical 2x4's on each end. i'm wanting to do a single 17' door because i hate double doors, my truck will barely fit through an 8' one, there's an extra opener to buy, and more work to build the center post.

will the two 2x12's hold up for that length?

i know anything will sag over time, but i don't want the house to fall down on me, or move a bunch right away. is a house with a 16' door built different than one with two 8' doors? would throwing another 2x12 or whatever above the garage door help brace it at all?

http://img205.imageshack.us/img205/1736/garage1bz4.jpg

[Vertnut]

I would say no. You need an "engineered" beam, or laminated beam, to replace those 2x12's.

[the spindoctor]

I would say no. You need an "engineered" beam, or laminated beam, to replace those 2x12's.

i don't want to replace the 2x12's, the garage door will fit perfectly underneath them as it is. i just want to know if it'll be ok to have a single door there instead of the center support like it had originally.

[bullet]

I framed for many years before I got into remodeling. Are the 2 x 12's solid all the way through or are they spliced where the center column used to be ? Is there plywood nailed in between them or is it just 2 2x12's nailed striaght together ? Today's code usually makes you use a laminated beam on garage headers. Is it 1 story or 2 story above the garage ? Which way do the ceiling joists run ? Are they resting on top of the header or are the running the other way off and resting on the side walls ? Before we started using laminated beams, we would often put a piece of 1/2 inch steel in between the 2 x 12's and run bolts through all of it to keep it from sagging, but this was mainly in situations where there was a second story above. If you are really worried you could get a piece of angle iron made and bolt it on the inside with lag bolts and then just fur the rest of the wall out like an inch with wood strips so that you can sheetrock over the angle iron.


Is there brick above the garage header now on the outside ? If so there is probably already a piece of angle iron on the outside of the lentil. also is there a gable above the garage header or is it a hip roof ? My mom has a 18 foot door opening on a house that was built in 1969 and it only has 2 2 x 12's spanning it with plywood in the middle and it does not sag much but she has a hip roof and there is no brick or gable weight above the header.

[Juiceweezl]

I work in this industry as an educator for designers, engineers, code officials, builders, etc. If you'll PM me tomorrow at work as a reminder and with the exact details (length of current span and length you want to span), I'll pull the WFCM design manual down and tell you what span the two 2x12's are rated for and make a recommendation for a new beam if necessary. Please let me know if they are full length, spliced -- how often, and how far apart is the splice, etc. I'll even check the post requirements. Also, let me know if there is a bonus room, attic, composite roof or tile/slate, etc.

-B

[the spindoctor]

I framed for many years before I got into remodeling. Are the 2 x 12's solid all the way through or are they spliced where the center column used to be ? Is there plywood nailed in between them or is it just 2 2x12's nailed striaght together ? Today's code usually makes you use a laminated beam on garage headers. Is it 1 story or 2 story above the garage ? Which way do the ceiling joists run ? Are they resting on top of the header or are the running the other way off and resting on the side walls ? Before we started using laminated beams, we would often put a piece of 1/2 inch steel in between the 2 x 12's and run bolts through all of it to keep it from sagging, but this was mainly in situations where there was a second story above. If you are really worried you could get a piece of angle iron made and bolt it on the inside with lag bolts and then just fur the rest of the wall out like an inch with wood strips so that you can sheetrock over the angle iron.


Is there brick above the garage header now on the outside ? If so there is probably already a piece of angle iron on the out side ad a lentil.

both 2x12's are full length pieces with no splices, 214" total, and no plywood between them. it's just one story with the rafters running perpendicular to the beam. no brick above the beam, and just a regular shingle roof.

now that i think about it, how much weight can those 2x4's on each side hold? should i put a 2x6 vertically on each side, then another 2x12 across? that would stiffen up the beam, the 2x4's, and still have something solid to mount the door and spring. hmmm.....

http://img205.imageshack.us/img205/4042/garage2mc3.jpg

http://img205.imageshack.us/img205/1481/carportsh3.jpg

[Vertnut]

I work in this industry as an educator for designers, engineers, code officials, builders, etc. If you'll PM me tomorrow at work as a reminder and with the exact details (length of current span and length you want to span), I'll pull the WFCM design manual down and tell you what span the two 2x12's are rated for and make a recommendation for a new beam if necessary. Please let me know if they are full length, spliced -- how often, and how far apart is the splice, etc. I'll even check the post requirements. Also, let me know if there is a bonus room, attic, composite roof or tile/slate, etc.

-B
That's the way to with this. I wouldn't take a chance.

[FSON]

First you have some movement in your stud columns and header/beam.

Without doing any calcs, I would recommend:

Adding a steel columns/flitched beam plate and the other half of the 2x12 to complete a flitched header/beam. Steel columns on both sides of overhead door should be bolted into concrete directly on top of perimeter slab beam.
Maybe overkill, but that's what I would do.

[Juiceweezl]

First you have some movement in your stud columns and header/beam.

Without doing any calcs, I would recommend:

Adding a steel columns/flitched beam plate and the other half of the 2x12 to complete a flitched header/beam. Steel columns on both sides of overhead door should be bolted into concrete directly on top of perimeter slab beam.
Maybe overkill, but that's what I would do.
Too much overkill, and while there is a lack of adeuate wall bracing in the picture, I doubt he needs a moment frame which is what that steel assembly would start to resemble. I didn't run any calc's either, but here's the answers from a few prescriptive design manuals. It helps to have a vast library in one's office. :D

WFCM Table 3.22A Header Spans for Exterior Loadbearing Walls supporting a roof and ceiling for a 20 psf dead load and 20 psf live load lists max span for 2- 2X12's for a 24' building width as 9' 5". Basically, the current setup is almost twice the allowable length. Table 3.22F of the same book calls for 4 jack studs to support a 3" header spanning 16'.

The Canadian Wood Council's span book lists similar spans of 9' 1".

Trus Joist span guides for headers supporting roof only suggests these options for a rough opening of 16' 3" and a building width (the length of the side wall of the garage) of 24'. If the side length is 30', the beam gets taller, but these will fit/come close to fitting in place of the 2x12's.

3 1/2" x 11 1/4" PSL 2.0E parallam beam or
3 1/2" x 11 7/8" (2 ply) 1.9 E microllam LVL.

Both require 3" bearing (2 studs) at each end. To replace the header, you'd have to adequately and temporarily brace the entire ceiling framing, rip out the header you have, install the new, and then remove the temporary braces. Let me know if you need more information.

[Vertnut]

Too much overkill, and while there is a lack of adeuate wall bracing in the picture, I doubt he needs a moment frame which is what that steel assembly would start to resemble. I didn't run any calc's either, but here's the answers from a few prescriptive design manuals. It helps to have a vast library in one's office. :D

WFCM Table 3.22A Header Spans for Exterior Loadbearing Walls supporting a roof and ceiling for a 20 psf dead load and 20 psf live load lists max span for 2- 2X12's for a 24' building width as 9' 5". Basically, the current setup is almost twice the allowable length. Table 3.22F of the same book calls for 4 jack studs to support a 3" header spanning 16'.

The Canadian Wood Council's span book lists similar spans of 9' 1".

Trus Joist span guides for headers supporting roof only suggests these options for a rough opening of 16' 3" and a building width (the length of the side wall of the garage) of 24'. If the side length is 30', the beam gets taller, but these will fit/come close to fitting in place of the 2x12's.

3 1/2" x 11 1/4" PSL 2.0E parallam beam or
3 1/2" x 11 7/8" (2 ply) 1.9 E microllam LVL.

Both require 3" bearing (2 studs) at each end. To replace the header, you'd have to adequately and temporarily brace the entire ceiling framing, rip out the header you have, install the new, and then remove the temporary braces. Let me know if you need more information.
So...I was pretty damn close? :cool:

[Juiceweezl]

So...I was pretty damn close? :cool:
In the ballpark. It would cost a fortune to saw down/mill a giant CA redwood to make a solid sawn beam to span that far nowadays. There are a lot of engineered options though (glulam, LVL, parallam, etc.) and a lot of heights/widths for them. The LVL's are most common, but the heights vary from 9 1/4" to much greater. Fortunately the manufacturers and other design manuals have handy span tables to tell you exactly what you need. I just happened to have them handy.

[FSON]

Too much overkill.
After reviewing the framing and exterior brick facade photos, I would still recommend a flitched or modified flitched beam or composite wood truss (using the existing header as a partial member). Also steel columns are recommended with a modified flitched beam on the back side of the existing studs to retain overall overhead door clear width.
I would not recommend replacing the header. That is a not an easy solution.

[the spindoctor]

After reviewing the framing and exterior brick facade photos, I would still recommend a flitched or modified flitched beam or composite wood truss (using the existing header as a partial member). Also steel columns are recommended with a modified flitched beam on the back side of the existing studs to retain overall overhead door clear width.
I would not recommend replacing the header. That is a not an easy solution.

thanks for the info, i'm surprised they are only rated for that small of a length. i'm going to see if the city inspector will come check it out before i do anything so i don't get shot down after its all over with.

[Juiceweezl]

After reviewing the framing and exterior brick facade photos, I would still recommend a flitched or modified flitched beam or composite wood truss (using the existing header as a partial member). Also steel columns are recommended with a modified flitched beam on the back side of the existing studs to retain overall overhead door clear width.
I would not recommend replacing the header. That is a not an easy solution.
Not to question your opinion, but are you a designer familiar with wood? The brick facade has no bearing on the header -- there is no brick on the outside of it. Further, the veneer doesn't add any gravity load since there is no brick above it. The side wall veneer won't contribute to the load over the header either. The only weight it is supporting is the roof/ceiling dead and live loads. Rafter thrust at the top of the wall is an issue since it's not likely there are trusses over the garage, but that's easily addressed with collar ties, or the ceiling framing via metal straps or 1x4's/2x4's (often the rat runs in the attic).
Further, why use steel columns for the gravity load of a new header? The only reason to use steel would be to create a moment frame that I mentioned in my earlier post. This area is seismic design category A and 90 mph wind speeds -- the lowest design values reprented in the building code. The current garage returns do not meet the minimum bracing requirements, so yeah, it'd be nice to reinforce them, but to do it correctly, you'd either have to build one of the prescriptive shearwalls found in the IRC or look at an engineered solution. The smallest one in the code is 16" wide, but requires two 4200 pound capacity embedded holdowns -- he can't retrofit those.

Any other option would require an engineer to design a wood shearwall or steel column as you mentioned. The steel would cost a bundle to buy/install, and the wood walls are going to be limited to a 3.5:1 aspect ratio per the code, so they won't fit in his available space. That drives you to a code approved pre-fabricated product like the Simpson Strong-Tie Steel Strong-Wall. It's available in widths as narrow as 12" inches, but has an option for a 15" wall on one side of the garage to count for both ends. All other methods are going to require braced panels at both ends.

If he doesn't want to replace the header, the easiest option is to just frame another wall section right next to it with the previously mentioned LVL header and standard framing material. It could easily be pushed up against the ceiling joists, and as long as attached sufficiently to the existing header, would prevent eccentricity in loading at the top of the wall. I'd still brace, tear out, and retrofit so that I didn't lose any space in the garage.

Either way, properly constructing shearwalls or installing a true, engineered steel column/moment frame has to be properly attached to the foundation. Most available systems will require 8" plus embedment of all thread rod with epoxy as a retrofit option. That means slab thickness of at least 12" in the area of anchorage. You can expect 2 bolts for any shearwall to resist overturning and another 2 plus for base shear. That's at each panel. A column would use at least 4 bolts for the same reason and to also resist rotation.

Oh, and as for the movement in the stud/columns and header/beam that you mentioned, any vertical movement of the beam is due to the excessive span not being able to suppor the gravity loads from the roof ceiling. Any lateral movement is due to the lack of braced panels/shearwalls at the garage return. Take a look at the picture -- there's not structural sheathing on the exterior of the studs.

I teach classes on this stuff if you do wood design. Shoot me a PM, and I'd be happy to discuss it further.

[FSON]

The current wood fastening application has deteriorated.
To keep the same clear opening, add steel columns, in wall, outside existing wood stud supports and attached to modified flitch beam.
The existing structure would not have to be disturbed.
Any structural wood movement can alter the bonded integrity of the brick wall.
Building codes are only a minimum requirement that has to be met.
I work all day long with people who design to meet minimum code, so I understand your point of view, that's my point of view.

[big_tiger]

I would add an extra 2X4 on each side, and you will be fine with anysize door. I have put more door with less wood that that.

[Fox466]

Pissing matches are quite entertaining... :D

[bullet]

both 2x12's are full length pieces with no splices, 214" total, and no plywood between them. it's just one story with the rafters running perpendicular to the beam. no brick above the beam, and just a regular shingle roof.

now that i think about it, how much weight can those 2x4's on each side hold? should i put a 2x6 vertically on each side, then another 2x12 across? that would stiffen up the beam, the 2x4's, and still have something solid to mount the door and spring. hmmm.....

http://img205.imageshack.us/img205/4042/garage2mc3.jpg

http://img205.imageshack.us/img205/1481/carportsh3.jpg


So the long ceiling joists are resting above the header ? or are they just like 2 foot long pieces resting on it? Are the ceiling joist actual dimensional lumber ? or are they trusses ? If you have a chance take a picture of the above joist where they meet the header so i can further see how it is laid out. As far as that header, since there is no gable or brick on the outside above it, you should be just fine leaving it like it is. You do not need to add a third 2 x4 under each end. 2 on each is standard for a header opening bigger than 6 feet. You do need to nail up the end 2 x 4 trimmers better into each 2 x12 and you need to add 2 2 x4 blocks above the header on each end so the weight is trnasferring down on the 2 cripple studs underneath. As far as the simpson bracing, I don't think it is necessary because the garage is attached to a perpendicular wall on left side and is not freestanding on each end. For this reason, the garage wall can not really move because it is tied to the other wall. If you are really worried about movement, sheath the inside of the garage header wall with 1/2 osb or plywood and then sheetrock it. Is the garage conversion currently list in your tax appraisal as part of the heated area on your house ? If so, make sure you get your tax value changed to reflect for a garage and not the heated value after you convert it.

[the spindoctor]

So the long ceiling joists are resting above the header ? or are they just like 2 foot long pieces resting on it? Are the ceiling joist actual dimensional lumber ? or are they trusses ? If you have a chance take a picture of the above joist where they meet the header so i can further see how it is laid out. As far as that header, since there is no gable or brick on the outside above it, you should be just fine leaving it like it is. You do not need to add a third 2 x4 under each end. 2 on each is standard for a header opening bigger than 6 feet. You do need to nail up the end 2 x 4 trimmers better into each 2 x12 and you need to add 2 2 x4 blocks above the header on each end so the weight is trnasferring down on the 2 cripple studs underneath. As far as the simpson bracing, I don't think it is necessary because the garage is attached to a perpendicular wall on left side and is not freestanding on each end. For this reason, the garage wall can not really move because it is tied to the other wall. If you are really worried about movement, sheath the inside of the garage header wall with 1/2 osb or plywood and then sheetrock it. Is the garage conversion currently list in your tax appraisal as part of the heated area on your house ? If so, make sure you get your tax value changed to reflect for a garage and not the heated value after you convert it.


i'm not quite sure what a truss is, but this is what is directly above the header. the roof overhangs the garage about 3ft, and i can't see exactly how the ceiling joists attach above the header.


http://img403.imageshack.us/img403/243/attic4ic7.jpg

http://img187.imageshack.us/img187/5208/attic3dj1.jpg

[Yellowstang]

We had a house that was built in the early 60's with two single garage doors. We had it converted to a large single door and the guy built a header to go behind the existing one, so the garage in the end was about 3 or 4 inches shorter. It was fucken solid as hell and never sagged in the 6 years before we moved.

If I recall, it was 2 12x6 or 12x8 full length boards nailed together, then 2 2x4's nailed together side by side on each end, maybe 3. I just remember it was a lot of wood and looked like it could withstand a fucken tornado!

[bullet]

i'm not quite sure what a truss is, but this is what is directly above the header. the roof overhangs the garage about 3ft, and i can't see exactly how the ceiling joists attach above the header.


http://img403.imageshack.us/img403/243/attic4ic7.jpg

http://img187.imageshack.us/img187/5208/attic3dj1.jpg


From that picture it looks as if the long ceiling joists are running parallel to the garage header and just the ~ 24 inch lookout joist are sitting on top of the header. Is that correct ? If this is the case, then you are fine pulling the center studs out as long as you take my prior advice and nail the header to the trimmer studs better and add double 2 x 4 blocks above the header on each end.

[the spindoctor]

UPDATE:

finally found a place that would run the calcs to tell me what i needed, and gave me paperwork to go with it to keep the city happy.

i ended up lag bolting a 14" LVL to the existing header, using 2x6 framing above and below to distribute the load to all 3 beams, and moving in 6" on each side with 1/2" anchor bolts for a 16' opening. seems beefy as hell, it didn't creak or settle at all when i took the center wall out.

http://img262.imageshack.us/img262/5368/newheaderyz9.jpg

the kiddos double checking my work.

http://img505.imageshack.us/img505/8618/dogsyo5.jpg

had to go with a slightly high lift door track to keep from having to play limbo coming out of the house.

http://img376.imageshack.us/img376/9655/garagedoor2kd8.jpg

i has a door.

http://img68.imageshack.us/img68/3195/47494119uv1.jpg

had to use a jackshaft opener because of the high lift and i must say it's a pretty nifty setup. super quiet and doesn't use any of the normal crap hanging down.

http://img68.imageshack.us/img68/1953/opener1ng3.jpg

now i just need to finish trimming up outside and paint, then tear out the old nasty carport so i can actually get my truck in and out. almost there. :)

[texanredneck00]

looking good , lookin good. wish i had a garage :rolleyes:

[black90gt]

mods to the rx7? :p

[the spindoctor]

mods to the rx7? :p

yep, i yanked out the rotary. ;) it'll have an LT1 one of these days. i've still got the 12a and 5spd if you know anyone that needs some parts.

[junior]

yep, i yanked out the rotary. ;) it'll have an LT1 one of these days. i've still got the 12a and 5spd if you know anyone that needs some parts.


how much for them???

i think i know someone who needs them

[miketyler]

Wow - looks great. I like the direct-drive door opener. So tell me - how does the motor sense when the door is up or down? Where are the up/down limit switches located on that model?

My shop has two 8ft doors and the opener mounts right against the ceiling. Clearance is so tight that the top segment of one of the doors actually rubs the rail going up and down.

[the spindoctor]

Wow - looks great. I like the direct-drive door opener. So tell me - how does the motor sense when the door is up or down? Where are the up/down limit switches located on that model?

My shop has two 8ft doors and the opener mounts right against the ceiling. Clearance is so tight that the top segment of one of the doors actually rubs the rail going up and down.

it has a little flip up panel on the front of the opener and the limits and force are really easy to adjust. it's a liftmaster 3800- they have the manual online in pdf.