Raising a Garage Roof

[rathersmart]

Hi everyone!

Here’s take 2 of the most serious project I’ve ever done.

The plan is to raise the entire garage roof intact up about 6 feet.

I would cut the existing 2x4 studs right at the sill. Then once the roof is jacked up i would sister in new 14 foot studs and sill. Then i would lower and attach the roof onto the new studs.

Do you guys know if i am ok keeping the 2x4 considering that the garage is not heated?

Also have any of you done anything like that or have any tips?

 

[The Cobbler]

14' is pretty tall for 2x4 . I would go 2x6
I helped a friend raise the roof of his storey & half to make it a 2 storey. one of my more memorable jobs. the biggest issue we had was the roof racked on us from not enough bracing, getting it back to fit took a fair bit of time.
he hired a crane to lift so we were a bit rushed too

 

[bad_idea]

I have seen a couple folks on this forum lift the whole building and scab in a short wall under the building. Then you can do a brick facade or something of the like to cover the lower section rather than residing the entire building.

 

[rathersmart]

14' is pretty tall for 2x4 . I would go 2x6
I helped a friend raise the roof of his storey & half to make it a 2 storey. one of my more memorable jobs. the biggest issue we had was the roof racked on us from not enough bracing, getting it back to fit took a fair bit of time.
he hired a crane to lift so we were a bit rushed too

I would sister in 2x4s to the original framing. In effect it would be almost like a 4x4 stud.

Do you think i can get away with it or still 2x6? I didn’t want to replace the original framing.

 

[The Cobbler]

yes, I wasnt thinking of that. probably fine. I assume no permits?

 

[danski0224]

Hi everyone!

Here’s take 2 of the most serious project I’ve ever done.

The plan is to raise the entire garage roof intact up about 6 feet.

I would cut the existing 2x4 studs right at the sill. Then once the roof is jacked up i would sister in new 14 foot studs and sill. Then i would lower and attach the roof onto the new studs.

Do you guys know if i am ok keeping the 2x4 considering that the garage is not heated?

Also have any of you done anything like that or have any tips?

So, are you removing the roof from the top plate? Or, leaving the roof attached to the walls and lifting that whole assembly?

I honestly think you would be better off to raise the whole structure and then construct a wall underneath out of cinderblock and fill the voids with grout. Then lower the structure and anchor it to the filled cinderblock. Door opening headers would need to be moved down accordingly, plus exterior finishes.

Setting the structure on cinderblock and then anchoring it down eliminates the hinge effect of setting it on a "knee wall". There may be an alternate method using structural sheathing to tie the two walls together.

You aren't saving anything by sistering all new studs, and you will still have to finish about 40% of the exterior (sheathing and siding).

Unless there are permit issues or appraisal issues, I'd take it down and start over.

 

[matt_i]

I had to check to see if they make a 14' 2x4. They do. Menards has it.

I think you're going to have to install center-blocking or Simpson TWB12. It would be worthwhile to check all of the sheathing and make sure its nailed off properly (which I define as 6" on panel edges and 12" across the field, #10d) and not haphazardly because there's a lot more foundation reaction to side loads a taller structure. Along those lines it would be worthwhile to increase the number of anchor studs via epoxy anchoring and large thick steel washers.

How are you planning to attach the studs to the new bottom plate?

 

[sweetk30]

I honestly think you would be better off to raise the whole structure and then construct a wall underneath out of cinderblock and fill the voids with grout. Then lower the structure and anchor it to the filled cinderblock. Door opening headers would need to be moved down accordingly, plus exterior finishes.

thats what i would do my self if i needed to lift up a building thats fairly open already .

 

[danski0224]

I have seen a couple folks on this forum lift the whole building and scab in a short wall under the building. Then you can do a brick facade or something of the like to cover the lower section rather than residing the entire building.

If it is a framed wall, there is the possibility of a hinge effect.

I would not recommend this approach unless one has an approved method to tie the two vertical wall sections together.

Filled cinderblock and anchors eliminates the hinge effect.

 

[aventino68]

I have seen a couple folks on this forum lift the whole building and scab in a short wall under the building. Then you can do a brick facade or something of the like to cover the lower section rather than residing the entire building.

This is what I helped a cousin do many moons ago. We jacked it up on a flatbed trailer parked in the middle and moved it to a new pad that he had built brick walls for.

 

[rathersmart]

yes, I wasnt thinking of that. probably fine. I assume no permits?

i will be getting permits for this

 

[rathersmart]

So, are you removing the roof from the top plate? Or, leaving the roof attached to the walls and lifting that whole assembly?

I am removing the roof from the top plate in tact. I will be bracing it to some beams and then jacking it up with a few jacks

How are you planning to attach the studs to the new bottom plate?

i am thinking about toe nailing the new studs into the bottom plate

If it is a framed wall, there is the possibility of a hinge effect.

I would not recommend this approach unless one has an approved method to tie the two vertical wall sections together.

Filled cinderblock and anchors eliminates the hinge effect.

yeah i am trying to avoid the hinge effect.

cinder blocks are an idea but i would have to lift the garage structure a lot more to get some working space to do the cinder block wall

one big complication is that this garage is somewhat attached to another "garage" structure it appears that the garage used to be detached a long time ago and at some point the owner decided to "fill-in" a smaller garage inbetween the house and the garage i am modifying. to tear it down means to tear down a lot more than i want to tear down.

 

[danski0224]

cinder blocks are an idea but i would have to lift the garage structure a lot more to get some working space to do the cinder block wall

one big complication is that this garage is somewhat attached to another "garage" structure it appears that the garage used to be detached a long time ago and at some point the owner decided to "fill-in" a smaller garage inbetween the house and the garage i am modifying. to tear it down means to tear down a lot more than i want to tear down.

The structure would only need to be lifted 2 courses higher than the desired end point. I'd estimate what could be done in a day, and lift the structure 2 courses higher on an as needed basis- this keeps it lower and presumably more stable unless cribbing is used to hold it up.

If lifting the structure is an option, then why is the "fill-in" structure an issue?

In any event, even following your idea of sistering in new studs will not be efficient and there is not much money to be saved and you will certainly not save any time.

I'd detach and stabilize the "fill in" structure and knock the rest down. If the "fill in" structure is worth saving.

The other possible issue is the slab. Is it in good condition? Does it have a thickened edge or even a trench footing? I'd hate to do all this work on an unstable slab.

 

[captain14]

GJ member JohnieMo raised his garage and added a boat port.

https://www.garagejournal.com/forum/showthread.php?t=283853

He has a YouTube video also if you search for it.

Another GJ member raised his walls added courses of block to raise it but I can’t recall the thread.

 

[spudley]

Raising just the roof 6' is risky business. Any strong wind and that roof becomes a sail. Better off raising the whole structure with a plan to get it on a foundation asap.

A buddy and I moved a 14 x 24 very solid garage (1x sheathing walls and roof) by jacking it up incrementally about three feet, maneuvered a 20' construction trl under it and then moved it to a nearby lot. We used a lot of cross bracing and let it sit on the trl until the newly poured slab with 2' knee walls cured.

In order to "float" a roof 6' off a top plate safely (if that's even possible for diy's), you'll need to build 14' walls inside the existing walls.

Seems like a lot of extra work and lumber...

 

[kbs2244]

youtube is your friend
search "raise garage roof"

 

[rust in the eye]

i will be getting permits for this

You'll need architect stamped drawings. The architect can better answer your question.
I understand some reasons for not wanting to disturb the existing walls but I suspect he'll tell you to raise the entire structure.

 

[u2slow]

You'll need architect stamped drawings. The architect can better answer your question.
I understand some reasons for not wanting to disturb the existing walls but I suspect he'll tell you to raise the entire structure.

^ Exactly.

I jacked up my car-port ~2 feet... a couple of 2x6 scraps at a time, using a hydraulic jack till I got there. Only supported on posts, so I just made up longer ones.

14 feet is tall for 2x4" walls. IMO, build most of the extra 6' out of concrete, or you really need to go to 2x6" studs.

 

[matt_i]

i am thinking about toe nailing the new studs into the bottom plate

I'm going to send you on the route of the Kreg Jig. Its setup nominally for 3/4" thick material but if you play with the jig and/or buy one that's setup for 1-1/2" or 2-by framing material, you put 3 torx screws into the holes, 2 from one side and 1 central/opposed.

It will outstrip any toenailed joint as far as connection strength. Make sure your fastners are rated for the corrosive pressure treated bottom plate. GRK screws are

 

[ddurrett896]

This guy wins