Concrete Slab Secrets No Contractor Wants You To Know!
ฝัง
- เผยแพร่เมื่อ 10 ก.พ. 2025
- #concreteslab #slabongrade #garageslab
This is part 2 of a 4 part series about this job and the two slabs we installed for this homeowner. Today we're pouring a 40' x 24' x 6" concrete slab for a storage building/garage.
A 6-inch thick concrete slab will be strong enough to support this structure and the RV, Tractor, Lawnmower, & car he plans to store inside here.
I know many of you are used to seeing grade beams or haunched and thickened edges for concrete slabs and in many cases those are good ideas to do.
This concrete slab will suffice in this case, where this building is just for storage and is a single-story building.
I've installed 100s of concrete slabs just like this one over my 45-year career with excellent results. The main key is properly installing a gravel base that will support the concrete slab for many years.
This homeowner has done that. I'm going to show you in this video how we pour and level the concrete for this size garage slab.
To learn how to install concrete slabs like we do, join The Concrete Underground for my personal training or purchase my Concrete Slab Course below.
EMAIL ME - www.everything...
THE CONCRETE UNDERGROUND - TRAINING WITH MIKE:
www.theconcret...
GARAGE FLOOR EPOXY FLAKE COATING COURSE:
www.theconcret...
MY STAMPED CONCRETE COURSE:
mike-day.mykaj...
MY CONCRETE SLAB COURSE:
mike-day.mykaj...
FOUNDATION CRACK REPAIR COURSE:
mike-day.mykaj...
GARAGE EPOXY FLOOR COATING COURSE:
mike-day.mykaj...
VISIT MY WEBSITE:
www.everything...
USE THE SAME TOOLS I DO:
MY DEWALT TOOLS PAGE:
www.theconcret...
MY MBW TOOLS PAGE: Battery Screed, Power Trowels
acmetools.pxf....
TOUGHSYSTEM® 2.0 DXL™ 5-in-1 Modular Workstation
acmetools.pxf....
DEWALT PENCIL VIBRATION TOOL:
amzn.to/2Km5Zis
INVERTER GENERATOR LIKE WE USE:
amzn.to/4fqhrEP
BULLFLOAT:
amzn.to/2U1Kx2F
HAND FINISHING KNEE BOARDS:
amzn.to/2TZmTUj
MAG FLOAT & STEEL TROWEL SET:
amzn.to/2IgmDOq
2" MARGIN TROWEL:
amzn.to/2G33KNn
CONCRETE PLACER OR KUMALONG:
amzn.to/2I00gxp
CONCRETE FINISHING BROOM:
amzn.to/2UytU2B
CONCRETE SCREED:
amzn.to/2WZxtwm
CONCRETE EDGER:
amzn.to/2GbGkEp
CONCRETE GROOVER:
amzn.to/2PaL414
Follow me on Twitter:
/ creteexpert
Follow me on Instagram:
www.instagram....
Follow my Facebook Page:
/ everythingaboutconcrete
Your two helpers look like a set of matched bookends. They both know their assignments, nice job!
At first glance, Darren and Luke do look like twins in this video.😂
2 little Brock Lesnar’s
I have never had the luxury of pouring a slab with no rebar, imbeded anchor bolt with holddowns ect. Must be nice not having anything but the concrete to think about. California makes everything hard. Good job putting that all down. The experience shows.
Were at 4ft frost here and with that much stone you get NO moisture, I did my one garage 70ft almost the same and it is dry as a bone, no poly but did a spread footing and it has been there now since the mid 90's with ALLOT of weight and nothing has EVER cracked or sank. Nice job fellas. 45 years, we must be close in age almost 64.
over 40 yrs old and been a blue collar boy since 16, even though i've never done concrete work for a job, i might've seen a few pours in my life, yall do good work. anyone talking trash just don't know any better. like my buddy's grandma used to say "Don't get mad at folk's ignorance babies"
You guys make it look so easy. Another great job.
Here in Australia most slabs are 4" or 100mm with adequate reo mesh its fine for cars as long as the soil has been compacted correctly
Excellent video, thank you.
I visited Maine this last summer for the birth of a grand daughter in Berwick. I had never seen houses with no gutters anywhere, and/or houses with almost no eves and end gables. I never liked the water reducers because they turned the concrete into silly putty. Same with the air entrainment. The micro fiber is huge for distributing loads and preventing cracking. They didn't have fiberglass rebar back when I was pouring. I would still have put a thickened footing around the outside. Main concern would be snow loads on the roof. I am so old, we would order the concrete by "sacks" as in 5 or 6 sack rather than 2500 or 3000 psi. They didn't have those vibrating screed boards. Those look nice. I never liked the rocker arm bullfloats. They were too wobbly for cutting and/or pushing high spots or low spots. I also preferred the square ended ones too. Main reason was that you could not make a slab flat all the way to the edge like with garage slabs. Some of that could be eliminated for those who crank the bullfloat angle too high. I would always screed the sides that you magged in by hand. Most of the time on a slab this size, we would do a 2 by 2 foot grid of 1/2 inch rebar. Easier than messing with the wire mesh, even the sheets. Only 2 guarantees you can give about concrete is one, it will crack, and 2, no body is gonna steal it. Always called the puddlers muckers. Old term for mucking out the horse stalls and/or the beer breweries. Oh, another "I am so old" all the concrete guys now use screws rather than duplex nails. Screws hold a LOT better! I never liked adding sodium for the concrete. I had heard that it will rust the rebar away. Don't know if it is true. We would use hot water a lot in the winter. The thing with both hot water and sodium, or was that calcium chloride? Anyway, they would help a bit with initial setting of the mud, but not with evaporation of the top water.... Every one I ever worked for told me I was too dang fussy to be a concrete guy. I probably should have been a finish carpenter.... Now I have a wood shop so I can be as picky as I want!
For what it's worth, a standard "6 sack" mix at
Great work. Wish we had more people like you in Congress📜🖋😄! Do the job and do it right (and pay on delivery 🤔). Thanks for the videos. 👍
I live in South Carolina where it gets HOT. For 34 years I constructed bridges. Temp changes here can be drastic and planning concrete pours can make you pull your hair out. Most of the mix we used is either 4000 or 5000 psi and without a plasticizer at 85 to 100 degrees you are asking for it. Most times I would order a 4 inch slump and pour the chemical in the truck on the job and take the slump to 7 inches. Also, more help is needed or it can sure get away from you. The thing so many do not understand is proper way to cure concrete. Many spray with sealer and call it a day. When you pour 5000 psi mix, you better keep it flooded with water at least 3 days. That stuff puts out a ton of heat. Spraying the top you are asking for failure. As for thickness, yes, add another inch if you are going to load it.
Really appreciated this video. The screeding demonstrations and comments were most helpful.
Thanks for the video. Great job.
Nice work fellas
Amazing job! You all make it look so easy!
When I was akid we always brought our own 100# bags of dry cal & put 1 - 100# bag to 10 yards for 2% in winter in Mass. Remember switching to power screed , vibra strike & the learning curve to get used to it.
Nice job on showing your secrets. Very impressive that your crew has figured out to not waste time moving material back and forth. Having an eye is essential. Nothing more frustrating than trying to screed a hole.
What factor do you use when calculating for additional concrete due to the compaction of the vibratory screed?
Have you ever used a micro rebar? My favorite is Helix Steel.
Keep the videos rolling 😎
Good job, pouring concrete is heavy work, ive done a bit here in the uk, we have to keep the reinforcing bars and mesh at least 55mm( around 2 and 1/8 inch) of cover to keep it from water penetrating into the concrete and rusting it out which bursts open the concrete, and around 3 inch of cover if its going to be exposed to water all the time like a harbour or culvert.
always enjoy your vids. I can relate as I do some construction here in vermont.
I'm a DIY guy. In 2022, I poured a 16x30x4inch thick slab.
I had to bring the corner up 16 inches with fill and stone.
All i had was a kubota and a string line.
I poured it at 4000 psi,5 inch slump.
To this day, February 2025.I have zero cracks in it..Zero!I covered it with plastic and watered it several times a day for 4 days
That's what good prep will do..!
Good relationships make good business. And good business means everyone makes money. 😁
This was so satisfying.
6" concrete slab 3500 is enough to support a 10 ton vehicle lift (like you see in an auto shop) with a vehicle on it.
Mike, I like your style.
Here in the UK, the steel mesh would never get through building regs. Here we elevate the steel mesh on small metal wire (lower gauge the the mesh) pyramids 50 mm, so the concrete forms underneath the mesh providing the minimum 50 mm what is termed coverage, and it is securely located within the slab and not at the bottom
In the states the contractors pull up the mesh as the concrete is spread out of the truck
@@stephendoing2253 Yes I know, but here in the UK that process isn't left to chance, variation, and relying on a ground worker remembering to do it consistently
Exactly. Same here in Australia. 25yrs of extensive experience from house slabs, bridgedecks, every column type and shape, steel cased bored piers down to 30m bedrock, stress cabled slabs in high rise pinnned to stairwell/elevator cores. I've pumped 100mpa lower core rises, all manner of sewer mains, sewerage pit constructions. it goes on n on. Fabric mesh should be no lower than 40mm from finished floor height under any circumstances. Period!
I worked concrete for a while. We just used bits of brick or other handy stone debris to prop the rebar up.
Are you actually so ignorant and arrogant that you personally know better than thousands of career tradesman in the US.... because you know what a rebar chair is?
I guess that makes me a Saville row tailor because I have used a coat hanger.
Here in the US we understand what the rebar actually does, and that it isn't really that critical - especially for a slab used for storage.
The building codes you are referencing are probably for habitable structures.
Either way, US citizens don't need any advice from Londonistan, but thanks.
Go back to thinking you are superior when you simultaneously don't even know that the US pours the most concrete of any developed nation.
This last fall I did kinda parking lot and drainage fix up with the entrance with concrete where some big semis from across the road seem to back up in there parking lot allot so I poured it 7" and the only thing with thick concrete is, its hard backing up when striking off, your deep in it, I had a hard time getting my feet out. LOL
Walk on the balls of your feet so you're not lifting up a lot of weight
Hi Mike,
What was in the bag that the third truck driver put in the tank?
Thanks
Hey Mike I wish you were in my area. I would have concrete all over my acreage! he-he
We have used 3.5-4" slabs for years (with a properly 20:00 installed base) and cars and pickup trucks did not crack them and we did not use rebar or steel mesh. I have heard the quality of concrete is worse now with less cement in it. Inspecting new home garage floors now most will crack if no expansion joints are put in. Too much water creating surface cracks I am guessing contractors are trying to stretch the load... thanks
Since when do we steel finish air entrained concrete ?
Hello from Northwest Pennsylvania! Nice work by you and the crew per usual Mike! I like how you explain several times about the positive effects of water reducer and how the wire mesh does NOT END UP AT THE BOTTOM of the slab contrary to what many believe. You are 100% correct on that, keep on keeping on. God Bless
nice job
What was the price for the 40' slab? Maybe I missed it. Looking to do one up in Stetson.
I’m looking to put up a 40x40x16/18 pole barn for my semi truck. Probably won’t be in there more than 2 days at a time. How thick should I make it? I’m going to do individual slabs ( 10x10 ) due to budget constraints. Obviously tied together with rebar pegs. And probably do them after I put the barn up. Any advice?
What did it cost?
Watching construction videos and reading about pouring concrete slabs I'm always amazed that all these professionals fail to use chairs to hold rebar or mesh in place, claiming that pulling it up works as good as chairs. Then, they claim that one thing is sure, that you will always end-up with cracks.
I did one slab (45 by 28 foot, 6 inches thick). I did the prep- work myself including a six mil vapor barrier and using chairs and hired a concrete company to pour the slab. The guys pouring the slab made the same claim, that it will crack anyway and that I wasted my money on the chairs.
That was thirty years ago and there is not one crack!
It just amazes me that these guys think that they can pull the rebar up and then walk on it without pushing it back down. Be "unprofessional" and "waste" your money on chairs and you will never have any cracks!
nice video.
Nice mike
So the concrete company can add warm water to the mix to aid curing in the winter time.
Doesn't that warm water cool by the time that it's transported , wait time for another truck to unload and the time to unload ?
You'd be surprised, it sorta stays warmish, certainly warmer than the ambient ground temperature. It works.
I agree on the 6" , my favorite concrete line is 4" is for sidewalks ...just like building a garage , if it 14' high , it aint a garage for me ..and hell no to 7x9 over head doors ...who came up with that wierd common size anyway ?
I would think that dobies or not would be in the contract when it comes to the reinforcement wire. My understanding in either rebar or wire mesh, dobies or other materials should be used to space them to the center, plus or minus, of said concrete depth. We have had poor experience with laying the mesh on the ground and then rely on pulling it up. A few years later, uneven cracks develop.
Why didn't you use small concrete block shims to hold up the peripheral rebar? I see you lifting it with the rakes instead.
How much is a yard of concrete in your area?
Well done, Mike-and of course you’re right about lifting those panels-or wire.
They use wire and rebar down south. My walkaway is 5" all the way. Then 8" at the steps. It has wire and rebar.
How much roughly does it cost to lay down a pad with these dimensions? Thanks.
Verharder in het beton heeft hier in het verleden veel problemen opgeleverd, dat het beton afbrokkelende in de nieuwe woonwijk in lekkerkerk, dacht ik.
Missing that green grass today.
Why not use fiber to hold the slab together. This way when your control joins crack. They won't pull a part enough for bugs to work their way up.
Still should have put plastic down moisture levels in the garage would be much lower if plastic is down doesn't cost much more at all.
Yes. Without question. If a roof is going over the slab at any stage. Plastic. Without so, rising moisture is inevitable no matter the base. You won't necessarily see it, but, place a cardboard box or unsealed timber on it, you'll see.
@larrybinge860 yes sir your right on!
I thought Air-Entrained concrete could not be steel finished ? They said the slab would get a power trowel finish ?
Madam X sees a car/truck lift in that solid 6 inch deep garage floor... Hey! ..Where is the hydronic heating PEX-ALU-PEX tubing? ...
I park a 45ft 60k lb motorhome, mini excavator, 2 bobcats, atv's, and whatever else we can cram in there. Was not a cheap project at all.
I also am a 45 year veteran of the concrete business. I'm impressed .
No offence to you, but mate, there's a lot of mistakes goin on there. Fundamental stuff.
Mike, we are about to build a shop in Texas and want to know what you would suggest for the foundation. It will be a 40x50x16 weld up metal building and we may service equipment up to 20k lbs. I have had many contractors tell me the slab needs to have so many support beams, 1/2" rebar on 18" centers, some say 4" thick while others say 6" (I am partial to 6")... any thoughts? I like watching your videos... great job!!
Rebar 1/2" or 5/8" coated rebar 18" or 1 ft on center tied and set on chairs or 1/2 bricks.
Home Depot sells them 2 in. x 4 in. x 8 in. Concrete Brick $0.50 each. sawcut or break bricks.
If you are pouring a turn down/thicken edge double up on rebar, use 5/8" epoxy coated. tied.
you will sleep better at night. the inspector should not mind. more rebar ok. but ask if its ok.
Concrete thickness 5" or 6" thick is fine. 6" is the way to go. we do gas stations @ 6"
Saw the joints. Caulk the joints use a good caulk. floor jacks roll better.
Penetrating sealer. with a finish coat sealer. Polish the floors 400 or 800 grit.
@@karconst6632 thank you sir! Our place is out in the country, so no inspections (Thank God!)... can't wait to get it started!
Many/most texas soils are expansive. High clay content. Talk to a building dept in your area for best practices..
I don't know who would say a 6" slab isn't enough, considering that probably 90% of slabs and driveways are an average of 4" (if your lucky).
Whats your base rock before the concrete? how thick do u make it before concrete?
Looks like ‘57’ rock which is ~3/4”. I think he said there was at least 1 foot of rock, compacted in 6” lifts.
Why dont you use rebar spacers? Wouldnt that be better than to try lift the rebar while pouring concrete and then step on the rebar later pushing the rebar all the way down? I thought ideally the rebar should be a little above ground like in the center of the slab.
It takes about 10 times longer to add the ree bar chairs/ blocks, lifting it to the center while pouring is far quicker and it doesnt sink after lifting it, it stys pretty much in the center. So its a matter of paying the team extra hours and the cost of the blocks for something they can do effectively for free while pouring and end up with the same result.
Really? The only place you hooked the wire is along the edge. You are correct about lifting the wire but you dont lift it in the center of the slab.
I watched a concert pore and suggested using shoots from other trucks to reach further. They told me the trucks couldn’t handle the weight
let me be that guy 'chutes '
@ thanks
You can't carry 336 lbs. LOL Nice job on the slab.
Mike, what are you hanging your Mag on? Do you carry a margin trowel and hang your mag on the handle?
What do you mean by "wet"? It looks like a liquid to me. Your men look like true artists. Down south where I am, there is allot of clay in the soil and I think a great many builders do a poor job of designing and pouring slabs. They tend to crack after a few years. There is a whole industry build around repairing cracked driveways and building slabs. The whole concept of having a slab poured makes me nervous.
What was the two bags?
Micro-fiber. I would have thought the driver would have added it while he was waiting for truck #2 to finish, instead of waiting until he got backed up to pour.
I hope it was macro ( 1 1/2 inch fiber ) because the wire was walked to the stone.
@@psidvicious Ahh, they add it the plant around here.
@@nicclark9791 Same here (S. Fla)
Hold on, the thickness of a DRIVEWAY is usually between 4 and 6 inches thick with the minimum recommended thickness being 4 inches. A 2X4 is only 3.5"
Those are not 2x4s
@mr702s looks like 2×4
They are 2x6 rough cut no nominal
They are 2x6 with a 1/2” gap at the bottom of the forms for 6” thickness.
Dancs to the left of me Luke is to the right,here I am stuck in the middle with you.
Kind of short sighted not put 10mil plastic under the slab. Why allow moisture to come up through? If he puts something down solid on the slab, when you lift it up it will be all moist where it made contact. Oh well.
I did concrete for the first 10 years of my career. we didn't have lasers. How can you make bird baths if you use a laser? I also did curbs. 38 years later the curb I built is still there.
What is a reasonable price per linear foot to install street curb ?
why is the mesh laying on the ground? shouldnt it be elevated a couple inches?
Mikes walking around pulling it up with a hook while they pour.
@@ApexFabrications Then it promptly drops to 1-2 inches off the base. Way way to low. Gotta be up near surface. Opposite of where its sitting in this video.
@@larrybinge860 so you said, should be elevated a couple inches. Followed by a comment of "drops to a couple inches". Now it needs to be near the surface. That's contradicting. Reinforcement needs to be in the middle 1/3 of flatwork, not near the surface. If you did flatwork you'd know that.
👍🔨
No contactor cares if you know or not, they are there to provide the product you are asking for
What is wire mesh
Wire grid
Surprisingly strong for what it is
“Wire mesh” is what everyone calls it but the technical name is Welded Wire Fabric or WWF. They were using WWF 6x6 1.4 x1.4. It’s the sheets of wire (5’x10’) that covers the whole area, over the rock sub base.
Something that is almost impossible to use right if anyone is walking in the concrete.
I don't believe in fiberglass rebar. They cannot be properly positioned and they have very little ductility. Wire mesh reinforcing is like spitting in the wind. Use 3/8" steel rebars 12" on center each way set on chairs. The outside edge of the slab should contain an integral grade beam minimum of 18" thick with 1/2 rebars top and bottom. I do like the 6" thickness of the slab and the compacted granular fill base was good too. This contractor uses methods that make it easier for him but will result in construction deficiencies. I am sure this contractor will saw the hell out of this slab to hide all the cracking that will occur.
Why is there no rebar or fabric
I'm just asking
There were 2 pieces of fiberglass ‘rebar’ all the way around the perimeter. You don’t need rebar or even wire mesh (WWF), if you add fiber to the mix, which they did. (You see the driver add 2 bags of fiber to the drum on the last truck). If by “fabric” you mean plastic vapor barrier, he said it is not interior space.
It is there. They laid it on the ground and poured concrete on top of it. It is still on the ground.
@kkarllwt I don't see it on the video
@@kkarllwt On an elevated structural slab, where rebar plays a critical role, do you know where the rebar is supposed to be placed? 3/4” from the bottom of the slab and 3/4” from the top, if top steel is even call out. It is most effective all the way up (to counterattack compression) or all the way down (to counterattack tension). Rebar is never called for in the middle. The midspan is neutral.
Wire? Why did you bother? the guy in blue and in orange walked on every inch of the wire after the concrete was taken. It is laying on the gravel. That is why I use 3/8 rebar on the correct chairs .The foot will feel the bar and usually miss it.
Obviously you didn’t see them pulling the wire up
@@chrisgaffney7265yyeah and they are pushing it back down when they walk on it it probably 1/2 inch up in the concrete at best
I never understand why they pull the wire up when building code says you're required to the reinforcement supported in the middle to upper 1/3 of slab during the pour. Aka use chairs. It's in IRC and IBC under concrete floors
Yeah, like 700 times....@@chrisgaffney7265
@@paulm5049 sounds like you know what your talking about, but if you’ve watch this channel then you also know this guy is highly experienced and does great work. He’s not hiding what he’s doing. It’s a garage floor not a runway
Not in Texas
only in U$A is concrete extremely complex
Why waste the time and money on wire mesh when it’s nowhere near the correct elevation? It’s doing absolutely nothing on the bottom of a slab. There’s so much bad information out there when it comes to concrete why perpetuate it? Slab on grade reinforcement adds essentially no compressive strength and is for holding cracks tight. That’s why it should be at the top 1/3 of the slab.
Use rebar and chair it up on brick.
Spot on! 100% There is not one slab on this planet that does not crack, if only hairline cracks. Yep, tis the reo (fabric mesh) which holds it all tgogether. Correct again, gotta be up near surface, ALWAYS and every circumstance or design.
Wet concrete is really not wet😂
Correct specification plasticiser added to a mix within slump tolerances is fine mate. Tis an amazing product but you don't have and extended period to screed and seal because in can come back to original slump (usually drier actually) prior pretty quick.
24 X 40' 6'' THICK SHOULD ONLY BE 18 YARDS,,,,,,,,,,,,,WHY 3 TRUCKS
He says in the beginning they are pouring multiple slabs that day
Watch the video again and listen next time.
Bottom third of concrete for wire or rebar brain surgeon
No wire, no rod, and they don't even know how to pour the job. I own my own business doing concrete and it's all wrong...
Sure is man, basic, simple fundamental rules out of whack.
No reo chairs no proper cover , you'd never concrete for me , and it would never pass a inspection
Its a private job and that is what the customer wanted. Im sure if the customer said to do it the way it should be done then the concrete guy would have laid a ground sheet and whatever other local codes he had to follow if it applied in the situation. Where i live a private job can pretty much do things whatever way they choose.
@scotthenry3401 if you realise when they walk all over they push the reo down , and it rots and doesn't give the strength its meant to
Why would anyone spend that much money on concrete and stone and not put a simple inexpensive poly vapor barrier between the concrete and Stone. You guys make no sense at all.
You should ask the owner, Mike said he didn't want it.
Without the vapor barrier everything that's metal stored in the building will age the same as throwing it out in the middle of a cornfield.. Not to mention mold growth on everything else. Somebody should have clued Mike on damage caused by ground vapor transmission🤨
Ridiculious. Only driveways and footpaths you wouldn't use. (Domesticaly).
@larrybinge860
I would install a vapor barrier under my concrete driveway if, I was going to have a car sitting on it. Vapor can cause condensation under your vehicle while it's sitting. That leads to corrosion and rust.
Hi Mike, the owner of this pad added the steel wire to the well-packed gravel base, whereas the owner of the pad in your last video, "City inspector makes builder ...," had no steel wire above his styrofoam base. Is that difference due to the inconsistency in standards that you highlighted last video or was it simply owners' preferences? 👍🏾💙🤍❤️