Did they not put any rebar uprights in your footing ?
Garage pads
- Thread starter Chump
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CatMan16
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I don't know for sure. I doesn't really look like it from the picture.
gates559
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Are those swirls on the floor the power trowel marks? if so it would really explain why it all cracked.
calgarysledguy
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How would power trowel swirl marks have anything to do with cracking?
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calgarysledguy
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We're each spot of 3 cracks is probably a pile. Usually they are marked on the concrete wall where they are.
This is common in new home construction. The houses are back filled with frozen ground if done in winter or not compacted properly in spring summer. Then the pad is prepped and resting on top of the piles. Now you have a concrete pad usually prepped at 3.5 to 4 inches resting on top of piles. Piles usually like 6-8 feet apart. Now the piles 10 inches round are creating a pressure point on the slab when the ground settles. The problem is that the 10 inch is just not enough area for the the 3.5 inch slab to rest on causing cracking on the pressure points when the ground under the slab settles. They probably won't do nothing about it unless the cracks open up or their is a deflection in the slab.
This has been a battle for ever as this also causes dips and unleve slabs between piles.
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New home warranty through the government will take care of that.... You need to get it done
teeroy
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yeah, I'm kind of wondering as well. our shop floor was poured in 1976 and power trowels were used.....that floor looks as cherry as the week it was finished 39 years ago
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big difference there, stuff was built with care and attention, not thrown together and hurried along like everything is today.
gates559
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Well if you can see power trowel marks in the floor it means the guy that did the concrete finishing sucks, which in turn means the builder doesnt care about his product and probably cheaped out on as much stuff as possible.
If he hires cheap trades to work on his homes maybe he uses 1 1/2 thick concrete in his garages.
rsaint
Active VIP Member
Got to say without the subfloor secured to the wall on you are nuts if its a full depth basement.
That is a 4' foundation that gets back filled 2' for a shop. Backfill both sides at the same time to keep the pressure the same. You are right though that you can easily push a wall over if not done correctly.
Power trowel marks left is called a "swirl trowel finish" which is the correct finish for an exposed garage floor. The more coarse the less chance of slipping with snow on your shoes but harder to sweep clean. Light swirl in my garage as I requested. Polished and burndt finishes are if you are going to put tile/sheet lino later or if by chance you like landing on your azz a lot in the winter - slippery as hell.
Garage slabs on piles are the norm for new houses and this is a jke as no builder does a true structural slab which is needed if using piles. You need 2" cover on top mat of rebar and 3" cover under the lower mat and 4" between the two mats of rebar. No less than 15m rebar and no more than 10" spacing on the rebar in each rebar mat. Without this basic pattern followed as a minimum you will not get one compression and one tension mat of rebar, just one big mass of steel not performing as required - for those counting it requires an 11" slab - 4" is standard. Good friggin luck getting that on a house - but without you get cracking as the ground settles from poor prep and the slab settles between the piles. Concrete is concrete and rebar is rebar - industrial(been in this game almost 40 years) or residential, if you use it incorrectly it will fail. Most houses get mesh in slabs or 10m rebar 24" on center - both good for decoration not any type of structural support.
And for those having wishful thinking that new home warrant will help just remember that ANHW was created by builders and is paid for by the builders and when you take the azzhat builers to arbitration their star winesses and supporters are ..................all the ANMW field personel. ANHW is not there to support home owners - sorry to burst all the believers bubbles. I spent 4 years fighting with a builder and had a lawer,ARCA roof inspector, structural engineer, P-eng and my experience on my team. When the builder came to the first day of arbitration he shook hands and greeted the arbitrators(2) and new home warranty employees by their first names - rigged ain't the word for what went on behind closed doors. I had enough of the BS and dug my heels in deep - how far some one is willing to go is up to you.
In the end I got my entire roof reshingled, garage slab replaced (which still has a 4" void below and will eventuall fail again) and my drive way redone twice. The cost of my fight was about equal to what I got back (just tabout $25K-would have been more but I had a little in house company help after hours) but hey....I beat those fuggin crooks! Unfortunatly I did not beat them because I was right (which by the way I was), I beat Reid Homes beacuse of an improper heading in their contract!!!! On the plus side Reid was rumored to have spent over $150K - they did not want me setting any presidensces for other home owners and I bet their standard contract got corrected.
How do I reall feel you ask...........slowly getting over it. Haha
Hope you get a new slab - flat work (non-structural) is only covered for one year during my little war. Good luc and go get'm Chump!
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gates559
Active VIP Member
lol nope, a concrete finisher that leaves power trowel marks is a poor finisher! if you want non slip there are plenty of ways to do it but leaving marks with the power trowel isn't one.
Rebar is pinned into the foundation, in residential the main reason the rebar is used if to help keep the concrete slab from dropping as the ground underneath it settles where it was previously excavated in order to pour the footings and walls. Basically 3 feet around the inside perimeter.
Rebar is pinned into the foundation, in residential the main reason the rebar is used if to help keep the concrete slab from dropping as the ground underneath it settles where it was previously excavated in order to pour the footings and walls. Basically 3 feet around the inside perimeter.
calgarysledguy
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Air entrained concrete is not to be polished finished.
Actually on the inside of attached garages the whole thing is dug out. That's why they put piles in. In Calgary anyways.
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gates559
Active VIP Member
Digging out the entire garage is not typical residential building practice across Canada. The pilings act the same as the perimeter pinning to hold the slab from settling.
You are correct on air entrained concrete as the more you work the concrete the more the air (bumped up to 5-7% from natural content of 3%) comes to the surface and will cause flaking. This is the same as for shake on hardeners that densify the surface of concrete - do not use air entrained concrete or the hardener tends to peel of.
Concrete exposed to freeze thaw cycles should alway have air entrainment at 5-7% so no surface hardeners unless spray on and do not overwork the concrete hence the reason most engineers call for a swirl trowel finish or a cross broom finish the the surface of concrete that is air entrained or exposed to freeze thaw cylces. Opening up the concrete by rolling the small 2-6mm rocks during either finish process is not acceptable as water in these open pores in freeze thaw cycles will quickly deteriorate the surface. Just a couple things to look for if hiring a finisher.
Edmonton pretty mush the same as Calgary on digging basements - if the want a ramp to the basement it goes through the garage area - nobody see the settlement after the garage slab is poured!
Where's Kyle when you need him. He would have a solution. Lots of reasons for the cracking. My money is on settling and not enough rebar. As stated, if piles are used, it becomes a suspended slab. Not a slab on grade. Totally different animal.
X-it
Active VIP Member
suspended slabs with insufficient or improper placement of the rebar or pilers placed on ground with proctor less than 95%.. the chances for cracking go up. Although I have seen slabs on grade with poor compaction and no rebar have no cracks at all, and slabs with 4 feet of awesome road material added with days of compacting and rebar added with 6 inches of concrete and lots of fine hairline cracks developed.
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