24x24 garage no footer

[godzilla]

Hi guys. First post, long time lurker. I have a 24x24 garage thats on a floating pad. The pad is 4" thick all the way across, with no footer. The wall height is 8ft, I'd like to jack the entire shop up to add 2ft to the sidewall height for 10ft ceilings. The slab isn't in bad shape. Whats gonna be the easiest and mist cost effective way to add a footer? I'm in central pa, so the frost line is 36". Thanks in advance, Pete

 

[nadogail]

Welcome Aboard, I can not comment on adding a footer to your garage Foundation but I am sure that with enough time and money it is possible.

Jacking up the walls and adding a section at their bottoms is well within the realm of possibility. There are several ways to raise the building, in fact it is theoretically possible for one man working alone to accomplish this task.

How many jacks can you get your hands on?

 

[Adk Mike]

My shop is also a floating slab. My climate is colder or at least as cold as yours. I'm On heavy soil the floating slab works best at least for me. Everything moves together. My garage a seprate building is a mess with the foundation. Doors bind in March. The plan for me is to remove the floor and foundation and pour an Alaskin slap. 12 Inches thick along the edge and 6 inches in the center. Lots of rerod.
It worked well with my shop.

 

[James-W]

Welcome to the forum.

Lifting a building up a few feet is something that is possible to do, either by yourself or hire someone to do it, but it takes time and there is a cost involved. It will take numerous bottle jacks and lots of blocking. You may need to use steel cables to hold the building together once you get it off the concrete floor. If the building will be "in the air" for a lengthy period of time, you may need to anchor the building down to objects that won't move (like a tree) in case of high winds. Once you finish raising the walls the doors and windows will need to be lowered.

I may be dead wrong on this, but I am tempted to say it would easier to raise the roof.

 

[matt_i]

Adding a footer down to 36" very difficult in my estimation. To get it inline with existing walls must cut back the concrete slab, excavate and pour up new footings, all with the building in the air and working carefully underneath it the entire time. Is it possible yes, will you hate it or its cost, yes.

To raise the roof may be a better choice. I think the only way is to re-wall the structure, heaven help you if a strong wind comes along while its being worked on and minimal uplift prevention is in existence.

 

[67ghiaTIV]

Are you adding a footer below the slab or a stem wall above the slab?

 

[T_R]

Why do you think you need a footer? Millions of garages are built on floating slabs with no issues.

You can raise it up and add 2 feet no problem with the existing slab. Stick framing or concrete block would both be fine.

 

[excavator]

agreed, leave slab as is and work on the frame

 

[godzilla]

The reason leaning towards do a footer then laying block three courses high. The current garage door is only 7' tall, I build 4x4s for a hobby and need at least a 8ft door. Also I plan on adding a 40x40 stick built addition with footers and a two foot frost wall, with 12ft walls on when the funds allow. And the current slab is a floating slab, not a monolithic slab. Part of the gravel at the one corner of the shop feel out from under the slab. So I figured I better do something with it soon. I felt it would be a good idea to put the current shop on a permanent foundation, instead of trying to tie a floating garage into the new one thats going to have one. I hate to do it but I think it might be easier to just jack the shop up, demo the existing slab and then pour a footer, lay block and pour a new slab.

 

[Handyfarmer]

one could dig down with a post hole digger, and under cut the slab some,

I would dig about 4 feet at a time and then fill with concrete, and after it sets dig some more and do again, if one wanted to do more concrete at one time dig a number of areas to pour at one time, If wanted.

by digging a tapered hole wider at the bottom, you will have a "footer" and a stem wall,
one level it off at the bottom of the slab, (fill up to the bottom of the slab), so there is no gaps and take a rod and work it well so it fills the voids,

I have done this type of rebuild on some stem walls foundations, and by doing sections one does not need to worry about losing or sagging the building, as most building swill span 4 foot Ok,

another advantage to this type of system one can make a pad on the out side of the building to jack or support the building from, if your planning on building under the wall you will need to not have direct support under the wall, but supporting it off the sides of it so you can build under it,

 

[Kpaige]

I am in MN we use floating slabs all the time. Around here there are a few that are over 40 long with 14 ft doors the guy down the road parks his crane inside and yes it is floating and stick framed.

 

[godzilla]

I wouldn't be so concerned if the previous owner would have built it the right way and did a monolithic slab with thicker edges, but he didn't and the whole slab is only 4" thick all the way around. I just got done reframing 3 of the 4 walls due to the fact that every single stud was cut and scabbed.

 

[ddawg16]

I see a big problem here.

All that work for just a 24x24?

Really?

Tear that ***** down....build a much bigger one the way you want.

 

[godzilla]

I know. I wish it was that simple. If I had the cash thats what I would do, but the trusses and roof are in good shape, and I just re framed 3 of the walls and sheeted them. We just bought the place a short time ago, so I'm kinda trying to work with the cards I got dealt for the time being.

 

[ddawg16]

Personally......then don't do anything. All that money for 2'?

 

[kbs2244]

You are “over engineering.”
You will not be adding that much weight, even with 3 rows of heavy block.

If you have a washed out corner, put in a retraining wall and backfill.

 

[buddyboy]

You are “over engineering.”
You will not be adding that much weight, even with 3 rows of heavy block.

If you have a washed out corner, put in a retraining wall and backfill.

+1

while you're at it go around the whole building and make sure everything drains away in all directions, downspouts to get water away from the building.

the building has been there for many years already and things have dried out and settled in, no need to stir things up under the building to raise it a few feet... if you where adding a story of living space, then that's a different 'story'

 

[Evilunclegrimace]

Go on you tube and see how the Amish move a building. Pick it up move it, dig and pour, pick it up and put it back.

 

[godzilla]

Thanks for all the help guys. I feel better now about my shop. I plan on buying two I beams and jacking it up when spring hits and add some block to get the wall height I'm looking for.

 

[Cyberbear]

If you are set on saving the existing slab, there are two possible ways to raise the existing structure. 1. It's more difficult, but you can dig out four foot sections spaced at four foot intervals, pour the footing and let it set up before doing the same in between. This is common when going two story over an existing structure and the existing footings need to be larger. 2. Raise the well supported structure and pour a two foot high foundation wall on the existing slab, being careful to tie the existing and new work together with rebar prior to pouring the new stem/footing wall. This way all work is done above ground and the slab is still free to float as needed. Just my opinion.

 

[cabin fever]

My garage is 24x30. 4" thick floating slab with 3 rows of block. 10' walls total.

Im in iowa and its colder then chit here. -5 last night. No problems in the 8 years since i built it.

In iowa you dont need footers unless its over 720 sq ft. I also have a 15x6 bump out.

 

[bdbecker]

No joke, when I opened this thread and started reading, I had to laugh. I have a 24'x24' on a slab with 8' walls and have been researching how to do pretty much the same thing that you are thinking of doing (two only two courses because of local ordinances) for the exact same reason (garage door to low for lifted trucks).

I don't have much to offer in addition to what has already been mentioned, but am curious as to what you end up doing and how you attack it.

 

[homebuilt burner]

If you are going to lift it anyway, why not set it on a trailer/wagon and move it then cut you slab back with a grunt saw and dig for the frost walls. Single form on the outside to the slab level and double form after that.

But in the end maybe just move the building and pour all new concrete insulated and frost walls then you know what you have. Set the building back on the new concrete and done. I would think if you are a 4x4 guy you should have something to move the building with.

 

[kerr]

I cant help but thin k you are going about this the hard way . I raised the roof on my 30x40 with no machines but a a/c jack I rented to lift the trusses up to walls I raised 6 ' . Raised doors to 14' .Taking the roof off really aint that big a deal . You dont have window issues , entrance door issues . Raise the roof .
Kerr

 

[godzilla]

Sorry for being absent for awhile. I'm going to have a mason come out and give me a estimate to lay block three courses high on top of the slab. But I will most likely jack the shop up with bottle jacks and cut the bottom plates off the wall and put 10ft 2x4s in scabbed to the 8 footers and install new bottom plates. I think it would cost me less money to do it this way. If the masons quote comes in under 1500, I'm going the block route.

 

[kelpaso1]

^^^ I think this will be fine. You're not adding hardly any weight by adding 2 foot 2x4 walls to the bottom. I don't know why all these guys are sayin undercut, dig, remove concrete for a footer. It's been fine the way it is and lifting it and adding 2 foot wall to the bottom is easy and not very costly.

 

[kmacht]

You realize that by raising the bottom up 2' you will now not only need new garage doors but will also have to re-frame any man doors, all your electrical outlets will now be 2' higher, any windows in the garage will now start at head level and go up, etc. Raise the roof and re-frame the garage doors bigger.

Keith

 

[godzilla]

Yeah I thought of that. I need a taller garage door anyways. The windows, I'd rather have higher for security. And as far as the electric, I'm basically starting from scratch. I'm still not 100% sure which route I'm gonna go yet. Thanks once again for everybody's help and ideas!