Need some help with a garage project that probably isn't typical

[SLCGARAGEMASTER]

I am lucky enough to have a roughly 75Lx40W foot brick building on my property. It is a flat roof that was built in the 1930's and it goes from a 10' ceiling to a 15' on the high side. The floor slopes about 24" down the length of the garage. I think some of that slope might have been intentional, but some of that is settling for sure. Water has been leaking into the building for years, and there was some sort of floor sump on the low side that has been filling, freezing, thawing for god knows how long. I replaced the center beam and rotten roof joists and will be putting a new roof on it soon so the drainage issue should be alleviated.

The next challenge for me are the load bearing outer walls. The brick walls have some pretty decent leans and bulges. I'd like to add some additional support for the walls, and I have two options in my mind.

Option 1. The current floor is about 10" of concrete from what I can tell. I have a friend who used some sort of ultrasonic scanner and he says it looks like it is 6" + a 4 " pour on top at some point. He couldn't tell if there was rebar in any of it. I've been meaning to cut a big patch and see, but for now I'm assuming there isn't any. I am considering using my hammer drill and drilling holes in a 12" wide pattern along the length of the brick walls. Then I can epoxy rebar into the concrete slab and pour a level pony wall. After that I could bolt 2x8-plywood clad shear walls to the pony wall and have it as a secondary support incase a brick wall ever gives way.

Potential issues I see with this: If there isn't any rebar, is it foolish to put this much load onto it?

Option 2. I could cut a 18" wide strip in the concrete in the interior of the building along the brick walls and trench it out 20" deep, back fill with 6" of gravel, and then pour a reinforced slab foundation inside of the building. I could put some insulation in the ground outside and heat the building, and then bolt the 2x8 shear walls to the new foundation. Basically, I could build a frost protected shallow foundation inside of the building.

Potential issues I see with this: I would have a total of 16" of concrete, and I am wondering if at some point the bearing capacity of the soil will be exceeded? Breaking and removing all of the old floor is a hassle I'm not sure I want to deal with either.

Would love to hear any thoughts you guys have, or any other ideas. Basically I would like to make sure that the roof doesn't ever come crashing down on me.

 

[SLCGARAGEMASTER]

Here she is in all of her glory back in 1933. Would love to preserve this piece of history.

 

[nadogail]

Welcome to the Forum from Southwestern California

 

[kbs2244]

get a experienced masons opinion on your wall "bulges"
you most likely have 3 course thick load bearing walls

you will need a guy with experience
most brickwork now days is just a layer over a frame building, non load bearing

I would guess you may have some separation of the courses due to seepage freezing inside the walls
that would be a major job to correct

 

[SLCGARAGEMASTER]

You are correct , they are 3 layer thick brick walls. The wall with the bulges is leaning and the roof is no longer in the bricks. There is a 2x4 wall holding the roof up. I have had some people suggest concrete walls but the cost is 170-250k depending on the quote and I want to avoid that

 

[kbs2244]

The correct way would be to rebuild the wall as it was origanly done
but that may be a budget breaker
for a good looking match think about a frame wall with a brick outer layer

 

[SLCGARAGEMASTER]

Which method do you think is best for the frame wall? Just bolt into the floor or try to pour a slab foundation inside of the building?

 

[johnnn]

Does the current concrete floor have lots of cracks. 10" of good concrete should be pretty strong even with out rebar. You could use load bearing steel columns to support the roof structure. Similarly to a precast concrete building with non load bearing walls. You would probably need new footings to do this properly. You probably want to talk to a good mason and possibly a structural engineer. 2x4 walls would probably be cheapest. If you are able to stabilize the wall an old school 3 coat plaster wall on the interior of the brick might help reinforce it.

 

[Zeke]

Lots and lot of old unreinforced masonry buildings got retro fitted here 30 years ago. One very common method was to create vertical channels in the walls and gunite or grout them with the rebar tied into new piers and as often as not, a bond beam around the entire top of the walls.

Others had steel beams through bolted horizontal and vertical. This is where an engineer earns the money. No guess work on this one.

 

[ez-duzit]

...rebar tied into new piers and as often as not, a bond beam around the entire top of the walls.

Others had steel beams through bolted horizontal and vertical. This is where an engineer earns the money. No guess work on this one.

This.

Get a competent survey and hire an architectural engineer. The first thing you must learn is if the foundations are sound and then how much of the original structure must be torn down and replaced.

Pilasters might be used to reinforce the walls, sandwiching the bowed walls between pairs of structural steel members drawn together using all-thread to draw them together, before pouring reinforced concrete pilasters.

 

[rktinc]

I have a similar situation in a 180x 50 building. That old brick and mortar just gets crusty and disintegrates. My building is pretty square and very little bulging. The back corner has been reinforced by digging it up and pouring several feet of concrete underneath it. I think the only try way to deal with it would be to use an inner steel structure to support the roof then tie the new steel structure to the old walls that are still staight and demolishing the wall sections that a leaning.

It may be more cost effective to reinforce the front and support the roof then replace everything behind it with new metal frame building. It would keep the look but give you a new building.

Big bucks to do this but some things are worth saving.

Good luck. Post up some photos.

 

[firebirdparts]

I'm not seeing how the pony wall in #1 does anything except add weight. Are you seeing a structural purpose for that?

Either way, I think your plans are reasonable, and you might even pull in the bulging bricks with some bolting if you do get some strong shear walls up there. If not you might just knock the wall down and re-do while your frame wall holds the roof up. That's heavy. Not trivial to move the support of it.

 

[walta]

Maybe you read about the brick building in Iowa. It seems the owner somehow found a contractor willing to ignore the engineers report and to try repairing the walls without building the proper temporary supporting walls. When the ineffective supports failed the building collapsed killing several people.

I think if you want to save the building the first step is to have a structural engineer look at the building and write a report telling what will be required. Yes, it will cost thousands of dollars but I think it would be money well spent. If your town requires permits as most will, this report will be a must have before you will get a permit.


Walt

 

[PoorUB]

I question if the building is worth saving! You have bad concrete floor, bad walls and no roof!

Sounds like a lot of work to save it and then you still have a hundred year old building in questionable condition.

Money maybe better spent hiring a company to demo it right down to the dirt and start fresh. It might not be mush more money and you will have better building in the end.

 

[SLCGARAGEMASTER]

I understand the point about demo and rebuild, but Im right in the city and the new code would require setbacks when rebuilding. I would probably end up with 20x50 when they get done with me.

I have reached out to a structural engineer to get some more opinions. I did hire one before, but his specialty was concrete and he proposed building a concrete building inside of the shop and pinning the bricks to the concrete. The quotes were between 170k and 280k so I would like to try to find something more economical. It might not be possible, but I want to stay at under 100k for the structural work, insulation, drywall, lights, etc. So basically I want to be all in 100k.

As far as the pony wall question, the purpose would be to add more attachment points to the existing concrete than would be possible with just the 2x8. It would also let me build to a level surface, the current floor slopes and isn't exactly even.

I am going to look into this pillaster idea. Is the idea that a vertical channel is cut into the wall and a pier footing is put in below with a concrete column? So basically building a pole barn with concrete columns and some sort of strapping between the columns holding the walls in at the top?

 

[ez-duzit]

Pretty sure the walls need not be cut.

 

[ycgoat]

I am not a structural person, If this was my problem and trying to DIY it I would add new interior steel posts rated and spaced for the roof load. I would cut out the slab where the posts were going and pour new 24”x4’ deep concrete peers. Once the new posts and roofing were independently supported I start demolishing the bulging brick and try to redo those sections. Once the walls were done I would level the floor with gravel and concrete. By the time I got all that done by myself I would probably be too old to actually use the space.

 

[Zeke]

Pretty sure the walls need not be cut.

But that's what they do.

 

[rayra]

I'd build a timber- or steel-framed skeleton inside the building and tie the roof and walls to it.

Determine what level of floor you can deal with and where and use self-leveling cement to correct what you must. That or add the minimal new pour to correct it.

Either way, I'd try to minimize the effort to correct things, before you wind up weakening or otherwise triggering the collapse you are worrying about. Forget about your stem wall and excavation plans.

 

[SLCGARAGEMASTER]

I'd build a timber- or steel-framed skeleton inside the building and tie the roof and walls to it.

Determine what level of floor you can deal with and where and use self-leveling cement to correct what you must. That or add the minimal new pour to correct it.

Either way, I'd try to minimize the effort to correct things, before you wind up weakening or otherwise triggering the collapse you are worrying about. Forget about your stem wall and excavation plans.

Would you put the concrete piers in like the comment above as well ?

 

[ez-duzit]

Would you put the concrete piers in like the comment above as well ?

It really only matters how the engineer wants piers installed. However I would think it appropriate to connect the pier rebar, on both sides of the wall, using interconnecting rebar in holes bored in the wall.

 

[paredown]

This.

Get a competent survey and hire an architectural engineer. The first thing you must learn is if the foundations are sound and then how much of the original structure must be torn down and replaced.

Pilasters might be used to reinforce the walls, sandwiching the bowed walls between pairs of structural steel members drawn together using all-thread to draw them together, before pouring reinforced concrete pilasters.

Love the look of the place, and I agree with all of those advocating an engineer and a complete survey before digging in.

Zeke's suggestion of steel also strikes me as a tidy (though likely expensive) solution. With the right crew/supplier it would be fairly quick to execute as well.