Help!! New Garage Floor Cracked..

I'm going to tapout after this comment as it's beyond my concrete experience. But, no rebar and a 1 foot footer? Is that even code in a frost area?

 

So you're saying they just poured concrete on the ground? Is there anyting under it like sand and plastic?, from the picture it looks like it's chipped at the score lines, again typical, the score lines are only what, an1/8 to a 1/4 inch deap?
That is going to happen just about 100 percent of the time, the saw will hit a small rock and kick it out, no big deal.

 

Oh boy, and with a heated floor...in balmy Wisconsin.. I don't think this thing will be looking too good in the spring.

But like I said, I am not an expert.

Out here they are doing strange things like that on houses; one foot wall with some sort of angled, buried ridged insulation, that is supposed to make up for the lack of the former code requirement of 42" frost wall.

 

Right you are, I'm thinking about the fact there is no reinforcement in that concrete, no rebar or mesh, it's ****ed from the get go.

 

Serious mistake. Your plastic shrink cracks are now likely to be the origin of cracking from differential settlement of the subgrade. Lack of primary reinforcing coupled with settlement of the subgrade would account for the unevenness at the cracks. How was the subgrade prepped? Who wrote the specifications for the job?

Bob

 

Right Bob, the OP didn't mention anything about grade beams or a perimeter beam, Here in Texas, every slab I ever poured had a least a 18 to 24 inch deap and 12 to 16 inches wide grade beam around the perimeter and internal grade beam all tied together with rebar for reinforcement.

 

here is is before pour.

Sand base and the plastic and foam. Pex

 

If it was intended that the cracks act as control joints, then they were cut too late. They should be sawed as soon as the concrete is cured enough to walk on, and the guideline for depth of cut is one third the thickness of the slab. Given that the temperature was 95º at pour time, I'd expect that if that slab was poured in the morning, you could cut the joints after lunch.

Bob

 

RC, it's hard for me to tell from that photo but if there are no internal grade beams then you'll have a problem. Now having said all that, I'm not familiar with the type of soils you have there in Wis. How deep is the top portion on the slab, where the piping is?

 

That must be a regional thing. I've yet to see it on garages here in the Northeast, but have seen it in your state.

My former shop (1989) was 42" frost wall buried depth, on a pre-poured foooting, and almost 1 more foot of wall above ground. So, about a 5' poured wall on the footing.

 

You spent all that money on a slab and making it heated and put no beams or rebar in it? I sure could have used that concrete them guys wasted.

 

The slab is 4 inches thick. The soil is mostly sand in this area and two trucks were hauled in and packed.

 

The lay of the land looks really good, and not wet. I'd be less worried.

 

I called and asked for rebars or wire mesh and was told twice I did not need them. Told it was no longer common practice.


The epoxy thing is a band aid at this point am I correct in this ***umption?

 

Ok fellas, I've been up since about 2:30 this morning, my brain is fried and the meds are wearing off. I'll check back in the morning and we'll go from there. RC, I know we do things different here in Texas, we have 14 of the most volitile soils in the US, there are a lot of thing that can happen.
Talk to ya in the morning man.
Later
Gary

 

4"??? Look up codes for thickness in Wisconsin. That's like sidewalk thickness. Right????

quick google search. 4" minimum. huh

https://docs.legis.wisconsin.gov/code/admin_code/comm/21/VI/19

https://docs.legis.wisconsin.gov/code/admin_code/comm/21/V/18

 

would you try and do fibergl*** work and not use the fibergl*** cloth? same concept.

 

Thanks Gary!!

 

One more question.
Was fibermesh concrete used???
If so, lack of mesh is not a problem...
Floating slabs are just that, meant to float up and down with the frost, and are not a problem for garage floors, even in WI, if properly poured. That thickened edge should have a minimum of two to three rebar continuous around the perimeter....and be at least 18" thick at the base, and taper up to about 30" at the underside of the floor. The purpose of saw cutting is to control the cracks, so they don't just crack at random.
Also the compacted sand should be tamped/hammered (with a concrete thumper) to compaction for every 2-3". Also a good water soaking overnight will settle the sand in the corners..
Was any of this done???

 

When I measure the depth before pour it was 3 in some areas and I made the GC add an inch around the entire form.

 

Had 2-3 rebar around the perimeter , did not seem like 18" deep more like a foot.

was not tapered. had a cut bout a foot wide as well


fibermesh concrete was used


4" over depth. , would guess some areas thinner maybe 3 1/2

 

Lots of expert opinion here, unfortunately, nobody in your area. I'd suggest stopping payment, get a certified inspector in at the contractor's expense, find out what to do to correct it, get the contractor to agree in writing what's to be done, photo do***ent everything and get it notarized. If you think the contractor is shifty, insist that a lawyer set up an escrow account to cover the repairs. The time to fix it might be a year from now, but the time to get the fix arranged is RIGHT NOW.

 

Concrete is my buisness . Has been since i could hold a come along and go out on jobs with my dad . Its what we do .

First off , in wisconsin , a 12 inch deep footing is as good as pouring a floater on top of the ground . Thaat 12 inches is doing nothing but adding weight . Its not effective . should have been a minimum 36 inches , and anyone that pours on sand is more than likely still using wire in thier concrete . Its pointless and dumb , I tear out ALOT of concrete that other guys pour that way . always insist on rebar and always on packed ca6.

Now . i wasnt there ,. i dont know what this guys stumbling blocks were . my guess is he poured it dry so he didnt have to be out in the heat to long . I see alot of guys pour way to dry and then run for the hose to wet the surface and try to save it . Thats a hacks methods , most of the time its a carpenter that carrys finish tools in his tool box because he thinks he can do it all . Leave it to the proffesionals fellas.

anyways . someone stated they thought it was just a surface crack...... No , thats a structural crack as sure as im typing this . The different colors are just where the Cure and Seal absorbed in certain areas and was heavier in others. The guy poured it pretty dry is my guess , and id also take a look at the ticket or call the redi mix and see what you got ? My guess is he cheaped out on you and went with a 5 bag mix . the way its already bleaching out is a pretty good indication . A strong 6 bag mix wont bleach that quick.

The guy actually should not have cut it . You have radiant floor heat and you are not suppose to cut a floor with radiant heat due to the risks of knicking a tube and then its totaly junk . His " remedy" of grinding the floor and filling it is bush league and screams amatuer right off the bat.

All i can tell you is how it should have been poured . How we would have done it and how it should have been done . You can compare the two from there.

Should have had a 36 inch deep footing cut right off the bat . and pour the footing by itself . Monolithic pouring is ok , when its done right , this was not done right.
pour the footing with horiz bars and verticle bars every 2 foot. Since it is in floor heat , your rebar options are limited so you have to beef the floor and the materials itself . DO NOT pour on sand . sand is for kids to play dump trucks in and grow watermelons. it whould have ca6 rock brought in and had the piss tamped out of it . The concrete should have been a 6 bag mix with fiber and since it was 95 degrees and in direct sunlight id have put an ounce of retarder in it to slow it down . and it would have had a half inch perimeter rebar around the entire floor.

now im strongly against any wire but in this case i would have used wire directly under the tubing to anchor the tubing to , it holds it down and allows for a little reinforcement " better than nothing but close" . And i would not have poured it that dry.

 

floor is to thin in my opinion , for being poured on sand . it really should not be changing levels in the crack . atleast not until october when the freeze heaves it up because the footing is to shallow.

Like said , all concrete will crack eventually . thats what control joints are for , only they should not be put in concrete with floor heat. He should have beefed the floor and materials up enough to compensate.

 

I think I am going to be sick!!

 

looking at your first picture , those small white spots, that does look like rocks close to the surface . Looks to me like it was hand struck and really dry.

if i was put ont he spot and had to tell you the problems .... Poured really dry , to thin and possibly with a cheap 5 bag mix. The footing should have been bigger and poured first , instead this guy poured a thin floor and hung a boat anchor off the side that didnt have a chance to settle first from being poured seperate. It is pulling it down at the edges and gonna cause seperation in the cracks. i can tell you that if it was mine , i would not put the weight of a new garage on it .

 

At least you don't have a garage built and it's 2 yrs down the road. To me you may have caught it before it's too late.

 

there was some concern that the time between the first cement truck and the second was too long and the crack line was along the pour.

 

Garage frame is on the slab

 

rafters went on yesterday