Sagging garage door opening


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Old 12-04-10, 09:15 AM
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Sagging garage door opening

Large opening, like almost 18 feet wide. Beam consists of two (2) 2x12x20' with plywood in the middle. I have a sag and I am concerned that the beam may break. The ends of the roof rafters sit on top of this beam. How do I get the beam straightened out. Should I remove and replace with those laminated beams or can I add another 2x12x20' and re hand the garage door?
 
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Old 12-04-10, 01:31 PM
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It sounds like the header needs to be replaced. You might be able to jack it up and sister another 2x12 to it, or maybe a steel beam would be better. I'm sure one of the carpenters will be along shortly to give you more info
 
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Old 12-04-10, 02:28 PM
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1. What is the rafter span?

2. Location, or ground snow load?

3. How many jack studs supporting each end?

4. Is the garage door supported by it off the ceiling joists as well?

Gary
 
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Old 12-04-10, 03:40 PM
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sagging garage opening

1. 16" spacing
2. snow load has never been a real problem, but can be deep snow fall from time to time. I have a mark on the door where the weather strip touches the door and there has been 1/16th change since I began checking it. Last winter we had a lot of snow, wet snow and I did see a measurable difference in my mark.
3. 6 each side
4. off the ceiling joist

When I built this garage I had two different lumbar yards tell me that the header would be sufficient. All three drew up the plans, material lists, and all. I kick myself now as these same yards have closed.
 
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Old 12-04-10, 07:00 PM
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1. The span is the distance between the outside garage walls holding up the rafters. Say 24' 4" span for a 25' garage footprint with 4" wide walls on each side, minus 1/2 the total span would be 12'2" span, which I could use to figure with.
2. Snow load is used by the B.D. to compute the load on the header, ie. 30#s.l. plus 15# dead load (materials) to figure how much the header will carry by multiplying.
4. Would mean it must also carry 2/3 the door when raised, the back-hang track carries the rest, if the ceiling joist bears above the header. 400-500# additional weight @ 2/3 = 300#.

Gary
 
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Old 12-05-10, 07:28 PM
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Red face sag

sorry gary.....
spacing, wall to wall is 24' even.

So, do I ignore the sag, do I replace the header, or do I put another 2x12x20' and go from there.

Thanks for the information.............

I guess I should add that I have had three contractors look at this. One said not to worry, another said to take one of the 2x12 and the plywood out and replace with lam beam, and the other said to be safe verses sorry he would sister another 2x12x20 on the inside and that would be sufficient. During a get together this summer a few of my friends began discussing the matter, the steel beam came up, but most everyone thought that was over kill.

So two lumber yards drew the plans, made the material lists, both went with the same beam
(2-2x12x20' and plywood) and three different contractors are telling me stuff that seems far apart.
 

Last edited by meanjimm; 12-05-10 at 07:44 PM.
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Old 12-07-10, 04:21 PM
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sag

Thought this site was full of educated information. You ask for help.... may be the problem is bigger than it seems. I was looking for an unbiased opinion, what I got leaves me believing the site isn't as informative as it is full of BS.

I guess Gary is still doing the math............
 
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Old 12-07-10, 06:49 PM
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Sorry, I've been busy somewhere else..... 12' rafter plus 2'O.H. = 14' x 18' beam span = 252# x 30#live load (inc. snow) + 15# dead load = 45 x 252 = 11340# possible. 2-2x12 carry 3000# 4x12 = 4200# (3-2x12) 6x12 = 6800# 8x12 = 9400# 3-1/2"x 14" LVL = 11000# pp.5: http://www.parr.com/PDFs/LP%20LVL%201.9E.pdf

Google- GBR in WA to see me and 3 S.E.'s, 15+ contractors, and .........

Gary
 
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Old 12-07-10, 08:10 PM
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sag

If I was to gain access to the outside of this header by removing the siding, trim pieces and such, would a steel plate be a viable option? Jack up the header to get level and lag or carriage bolt every 16" on this steel plate the entire length. Say 1/4" may be thick..... that way I don't have to mess with breaking down the entire garage door, tracks, ect.

Say Gary, the information was great, appreciate it really. You seem to be on top of your game.... I on the other hand am not a general contractor, I work inside a federal prison, surrounded by rapist, murders, and such, been doing it for almost 30 years. But thanks again, I will review the link, may be I can make heads or tails out of that.

I'm looking to fix the sag, not concerned with price as much as I am function and time for the work. I have lessened the load above the door the best I can, the wife loves to store stuff there. I continue to watch the mark to make sure the sag isn't getting worse and the plan is to do something about this in the spring. Kinda why I put this out there.
 

Last edited by GregH; 12-08-10 at 03:22 AM. Reason: Remove email address which is against our rules.
 

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