Having to replace a garage door header (16 foot span) due to sagging.

My question is regarding supporting the roof while I remove the header.
It's a cape cod style house so the roof is on a steep pitch.
There are no birdsmouths on the rafters and from what I can see they are nailed into the joists and toenailed into the top plate.
Since I will also be replacing the top plate I will be cutting off the toenailed nails and don't want to risk the roof shearing off or shifting.

My initial thought is to nail/glue a 2x10 wedge shape onto the ceiling joist where it meets the rafter to make a flush surface. Then nail/glue a plywood/osb gusset on that side.

I am also doubling up the ceiling joists so this would give me the 4.5 inches per ceiling joist near the header to put my support on (wedge, ceiling joist, sistered joist).

I know there's a myriad of strong ties out there so wasn't sure if there was something better to do than the wedge+gusset. It doesn't look like the Simpson VPA will work since this isn't new construction and the rafter/roof is already in place.

 

Your description is pretty good but some pics would help. Is that detached garage? Can the header be jacked up & re-supported instead of replacing it? If not, it sounds like the first thing that you need to do is build a temporary header under the next joist behind the header. One time I used a Come Along to stop shifting.

 

Sure thing. Here are some photos- let me know if anything else would be helpful. If the wedge/gusset part description isn't very good, I can draw a photo and attach it. Basically the sandwich of the rafter will be: gusset | wedge/rafter | joist | sistered joist.

It's an attached garage with the house door/wall being to the right if standing inside the garage looking out (as the photos are). The garage opening is boarded up with the osb to keep the wildlife out.

And now I'll give you more information than you probably care about...

Initially I had planned on jacking up and fixing the existing header with a steel plate but I felt like while it would be easier it had some downsides to it that I didn't like (not saying it wouldn't work, I just didn't like them )

The existing header is just (2) 2x10's with the osb between them. I can't recall exactly (it's taken me awhile to slowly jack it back up) but the sag was around 1.5".

While there isn't living space above the garage, there is significant storage space.

Photos - currently I have 4 jacks under it. The one with the 4x4 against the joists really isn't doing much and is primarily a safety. The bottom plate is missing against the jack stud in the one photo because I had to see for myself if it truly was just 2 2x10's or if it was 3.

2x4 walls.

I am planning to place a couple 4x6's against the joists the length of the garage near the existing header and move the jacks one at a time to it as my temporary header. I'll either have 4 or 5 jacks under that depending upon how it spaces out. Again, this will be after I sister the existing 2x10 ceiling joists. They don't have a lot of sag to them but they are also slightly over the span allowed for a 2x10.

I am replacing the existing header with a 20' i-beam that has 20' 2x10's bolted/glued to fill it out. Top and bottom plate will likely be ramsetted/glued.

 

In your OP, you said that you were replacing a garage door header but it looks like a side wall in the pics. What am I missing? If it is a side wall, you have to look at the slab or the footings.

 

May have to help me out on a 'side wall'. Is that an eave wall (vs a gable)?
The header from the photos with the post jacks under it is the garage door opening. I've attached osb from the outside just to keep the animals out after removing the garage door and hardware. The garage door is on the eave wall of the garage structure itself though.

Does that help or am I muddying the water?

 

You can just build a temporary wall out of 2x4s under the ceiling joists. Build it as close to the header as you can but leave yourself room to get the new header in and out.

 

Ok, that's what confused me. Xsleeper is correct. However, I still like the steel plate idea. What didn't you like about it.

 

Ok great. Glad it makes sense.

I just called Simpson and they don't make anything that would really work well (not surprised) so curious if there are any better options to the wedge/gusset approach.

 

You are making this more complicated than it needs to be. See post #6. After the header and top plate are installed, install Simpson H2.5's.

 

I think your question is to how to make sure the roof rafters are properly supported by the temp wall you are going to build. How are the roof rafters tied to the ceiling joists currently and how much meat is there to catch between them. My understanding is you want to build out a piece under the rafter and then tie the rafter to the joists with a gusset of plywood.

 

The gusset would be overkill and is not needed if there are sufficient nails in the rafter to ceiling joist connection.

 

@czizzi - That's exactly it. I've covered this whole project miles in my mind so probably not explaining it all that well.

I'll have to check this evening for sure but I am thinking it's 3 nails connecting them at the overlap. Not sure the measurements of the overlap but can get those.

@XSleeper - I won't argue at all that it's more than likely overkill and that I am overthinking it. Been known to happen. A lot.

Some middle ground might be that I could cut the sister joists ends at angles matching the rafters and then use them as my gusset spacer. Downside is that the sistered joist would only have a tip of the angle sitting on the topplate. Although the gusset could make up for that. Part of me is thinking the back wall is birdmouthed so this idea is likely out.

 

You wIll probably want the sistered joist on the opposite side from the rafter. And you should put a couple extra nails in the rafter to ceiling joist connection to be safe, distribute them all around the connected area in a grouping, not in a line.

 

Thanks. Checked last night and the opposite end is birdsmouthed so the sister will have to be on the opposite side from the rafter.
I'll sister the joists first and then either go the route of adding more nails or doing the gussets (maybe just every other one).

Appreciate the feedback