Raising overhead joists in my garage. Is this a good idea?

jpearson311

Hi all. In my garage, the over head joists are really low. They are 2"x12"x20' and there are approximately 6 of them. The walls of my garage are standard 2x4 frames spaced 16" apart. The ends of the joists are nailed to the vertical 2x4s on the left and right walls. There is also approximately a 16" gap between the joists and the tops of the walls. What I'd like to do is remove each joist, one at a time, and raise them so they are flush with the top of the walls. Each joist is connected to a vertical 2x4 on the walls with 2 normal framing nails on each end. So what I'm thinking of doing is starting with the first joist, knock it out at each wall, raise it up flush with the top, nail it back in and then do the 2nd, 3rd, etc. If I do this one at a time, is this safe to do? Check out my attached picture and let me know what you think. Thanks!

Attached Thumbnails

 

Rory Read

JP,

I haven't come across your "as is" lay out. Ceiling ties/joists typically sit on the top plate and flush to the rafters. Maybe someone wanted that space for added storage?

I don't know/see a reason not to proceed, but you might consider some beefier hardware. 2 framing nails seems a little underwhelming to carry a 20' member that typically sits on a plate. Maybe some bolts?

Good luck!

__________________
Rory

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Portland, OR

tpolk

definitly more fasteners

__________________
The older I get the better I was

Gary in WA

The bolts are only as good as the nails into the top of the studs through the plate. Could you post a picture?

Be safe, Gary

__________________

jpearson311

Hi you guys. Thanks for your replies. I know what you mean about the joists sitting on top of the plates, but in my case, they don't. I think it's because of the way the roof was constructed. It's an X frame pattern where there is one primary peak, in the middle. I took a picture of one of joists where it attaches to the framing. You can see the gap between the joist and the top plate of the wall frame. I want to move it up, but after looking at it, I'm not sure if I even need them at all. If I take them down completely, will my walls cave in? See attached pic. Thanks!

JP

Attached Thumbnails

 

Scuba_Dave

Do not take them down
You do need rafter ties between the walls to keep them from spreading out
This occurs slowly over time

Does that 2x under the rafter extend all the way to the bottom 2x plate ?
If so that is pretty good support

Do you have a wide pic of all the framing ?

Gary in WA

With a 20’ total span, the rafter ties (2x12’s) need 6 nails each side for a 4/12 roof and a 30# snow load. That is nailing into the heel of the rafter or using a Simpson connector instead. The ties should be next to the rafters, not down the wall any. A 5/12 roof needs 5 nails each side. http://www.engineersedge.com/civil_e...onnections.htm

The 2x4 rafters are over-spanned if D/F and no snow load = 8’11” span max.

I would move them up and nail them to the rafters where they belong. They sure look to be 2x10’s…..

Be safe, Gary

__________________

jpearson311

Ok Gary, thanks for your reply. When you say move them up and nail them to the rafters where they belong, do you mean set them on top of the top plate of the wall frame and nail them to the rafters? I'm assuming the rafters are the angled 2x4s directly under the roof. If this is the case, wouldn't I have to miter cut the ends of the 2x12s so they fit snug with the pitch of the roof? Should I also shoot a nail from underneath the top plate into the joist (2x12)?

I looked at the simpson ties, but I'm not sure which ones to use. Can you send me a link of which one's I should use? Also, it is 20' across, the joists are 20' long, but I have a support mechanism in the middle that I'd like to take out (see attached pic). If they're 2x10s or 2x12s and are 20' long, they won't sag if I take out the middle support system will they? Thanks!

Attached Thumbnails

 

jpearson311

Thanks for your reply scuba. The height of the walls from the bottom plate (footer) to the underside of the top plate is 7'10". The 2xs underneath the joists do go all the way down to the footer (see attached pic). This is the best shot I could get considering I don't have electricity in the garage yet. Thanks!

Attached Thumbnails

 

HandyDave

I hope you dont think im high jacking your thread, but can I ask what software progrram you used to draw the picture in your beginning post. I am a very visual person and would like to make similer drawings of my projects. Thanks... Happy Remodeling

Handy Dave

jpearson311

Hi Handy Dave, no problem. I used a program called Adobe Illustrator to make that graphic. I'm a web designer for a living so I know how to use most of these relative applications. All the best.

JP

Rory Read

Scuba Dave noticed that you have jack studs under the ties. To me, that is a reasonable alternative to seating it on top of the plate.

If you move the ties, you should have longer jacks. In typical wall construction, a jack should run continuously from the member it is supporting all the way down to the bottom plate. If you don't want to rip those existing jacks out and choose to place a short piece on top, you should sister a new stud that runs plate to plate creating a sandwich for the ceiling tie. Use a lot of nails. I wouldn't worry about the bolts with that construction.

I personally would not rebuild the entire rafter system unless it was starting to fail.

I would not take out the center bearing wall if I was storing much of anything on top of the ties.

Cheers,

__________________
Rory

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Portland, OR

jpearson311

Hi Rory, thanks for your reply. I understand putting a total height jack under the tie and if I leave them connected to the wall, that is exactly what I would do. Would it be possible to set a 2x10 or 2x12 tie on top of the top plate after it's already built? If so, how would I find the angle to miter cut the tie so it fits snug with the roof pitch next to the rafter? I definitely want to take out the middle support. To support this, after I moved the ties up, I would add additional 2x4 supports that connect to the ties and to the above rafters on the other end. Like a real truss. It's being used now for only a little bit of storage weight. Thanks!

JP

Rory Read

JP,

I don't think you can put the ties on the plates now. The rafter size and pitch is going to require too much of the rafter to be cut away. It's the width of the wood sitting on the plate that counts, so, if there is only 6" left after that cut, it doesn't matter that it's 2x12 in the middle. It's all bearing on the portion that's a 2x6, and that's too small for the span.

If you play around with the span calculator at http://www.awc.org/calculators/span/...rcalcstyle.asp, you will see that a 2x12 can handle that span as a ceiling joist with only minimal loads on top. You use that overhead space at your risk.

Joist to rafter framing will help support the roof. It is not intended to strengthen the load bearing capacity of the joists. I think you would need beams under the joists if you want to remove the center wall and use the joists for storage.

__________________
Rory

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Portland, OR

Scuba_Dave

I would either raise them up so that the top of the joists hits the bottom of the top plates
OR
Possibly notch the beams & install them around the top plate?
Then install a new support stud underneath (crude drawing)

Seems like a lot of work for very little gain
But I know having headroom makes an area seem much bigger

Thoughts?