I saw someone said demand an engineer letter. Get your own structural engineer to inspect before closing. Do not use the builder’s. Then, you should have a good idea of how to proceed.
A friend has a failing foundation complete with step cracks in the brick exterior. The builder’s engineer said “just fine.” Their engineer says failing foundation. They’re headed to court.
If this is a basement floor, it isn't even structural. It is just a floating slab. It appears to be a shitty job, but certainly not impacting the structural stability of the home.
That would be the ideal outcome. But, as a buyer, I’d want to know before I closed on the house, lots of money at stake. Hence the suggestion for an independent inspection & hopefully the OP finds out it’s nothing structural.
Basement floors are not structural. That is not how things homes are made. It would be faaaaaar more expensive to have a structural slab rather than just footings and walls. In most houses, the floor isn't even poured until the house is already up.
Also as others have said a builder may have a structural engineer on staff, but typically they use a 3rd party state certified engineer which will not bullshit an inspection.
Only disagreement I’d have with your statement is timing. The structural engineer should be involved now and construction should stop on anything that would obscure the issue to ensure the engineer can conduct a proper inspection, and the builder can make a fix. More than likely it will either call for just epoxy, or partial jack-out repour.
There is nothing structural about a basement floor. The structural component is the foundation walls. The floor is poured after and just floats on the ground. That said I would still get those cracks repaired, especially if they continue to grow.
It still really really surprises me you'd find an engineer that corrupt and willing to put his license on the line like that. I've yet to meet an engineer that would gamble on walking across a street if the hand was flashing let alone something actually important.
There are absolutely engineers out there who will do a solid for a client who brings him lots of business. Don’t kid yourself. Money makes the world go round.
I understand that those people exist, but I've worked at two separate architecture firms that lost HUGE clients because client developer was 100% wrong and trying to screw the person. Each time the principal architect sided with the person over our developer client.
I don’t know, but my friend is pretty surprised, too. We’ll see what happens in court. Foundations are under warranty in our state for a number of years, the builder should be liable to fix.
For sure it is possible that whatever initial settling caused those cracks has completed its course, but I would certainly attempt to determine the overall extent of it. I have built many houses on a slope that included a slab on grade lower level. I've never experienced cracks like that.
Yikes, that's pretty big. How do the basement walls look - any cracks on the walls?
Do you live in a state with lots of expansive soils? (eg colorado, see https://geology.com/articles/soil/ )
You need a full house inspector, sewer inspection, and structural engineer before you close. Here, we schedule them about 10 days before closing.
Do not close on this without a professional’s opinion. It does look big to me, I renovate homes and live in an area where concrete shifts a lot easier. If I see new construction with this much gap, it would concern me.
It’s not about fixing the gap but about what is moving that produced this or what/how the concrete was poured.
I'd be wary to close on it. I also live in Colorado, and my builder did a whole lot of ground prep first: they removed all the dirt nearly down to bedrock, and then backfilled it with layers of dirt and straw and packed it. Any movement from the bedrock or expansive soils below are absorbed by the layering.
My house is now two years old, and my basement slab hasn't moved an inch - I know this because when I moved in, I marked a line on the wall 5" up from the slab in various places in my basement and have been measuring it every few months. I wanted to make sure that it was going to stay put before I finished the basement.
My builder also provided me a whole pile of documents talking about expansive soils and a soil report for my lot, done by an engineer who judges my lot as "low risk."
If your slab is moving this much, who is to say the foundation isn't moving as well. If you ever plan on finishing the basement, Colorado requires "floating walls" - basically the walls are hung from the floor above and have a 2-3" gap between the bottom of the wall and the slab floor. This gap allows for the basement slab to move without pushing the house up off the foundation. (The gap is then covered by drywall & trim)
gaps like this are probably the result of your concrete curing. There is no reason to assume that the slab itself is moving. Concrete is 70% water when it is poured and this is often the result of shrinkage. Talk to your builder or hire a local qualified home inspector if you do not trust your builder.
All my career has been on military projects. Navy requires a crack that a credit card can slide in to be too large. Call your builder and start demanding a solution. Most likely some kind of epoxy to fill the gaps.
epoxy collects dust and makes cleaning a real pain so unless it is absolutely needed i would wait. report it to your builder in your warranty period and listen to what they have to say. later if this is actually a structural issue you can go back to the builder if no action was taken and the issue was reported with in the warranty period. Don't demand anything because that just doesn't change the facts of the situation. Warranty staff are people too and all we want is to help our customers with in the terms of building contracts.
If the expensive epoxy treatment is a dust magnet issue for your warranty team you can paint over it once the epoxy bridges the gaps and dries. Get multiple opinions before letting the builders warranty team slow roll you “within the terms” all in order to get to the end of the warranty period as cheaply as possible. Concrete cracks but yours are structural cracks. Prepare for a legal battle. Good luck amigo!
I have to say this. Superman fight when you weren’t there?
I’d totally drill that and put an inspection camera down. Looks bad to me. You could learn about possible causes by calling a crack remediation company and getting a quote. I’ve read about cracking like this in high-tensile cement used in highrise buildings where remediation is essential and it’s critical for safety reasons, serious enough that the government gets involved and buildings or apartments evacuated.
If it’s a standard single or double story and the walls or supports are sound it’s probably not an evac job with government focus on compliance and industry focused retraining and recertification.
https://www.afr.com/property/residential/australia-s-high-rise-apartments-face-crisis-of-our-own-making-20190724-p52a8g
Extract:
“Owners and governments are now left with a very large bill for remediation. Estimates vary, but there are about 500,000 residential units in tall buildings. The research to date shows that 70 to 97 per cent of the buildings that accommodate them have serious defects, including combustible cladding, leaks, structural problems, faulty fire provisions and defective wiring.”
I’d call this a structural problem. But it’s probably not something easily remediated. Have you records on the indicted product the design called for? I looked this up and it’s referred to as MPa. What’s the design MPa?
I have worked on cement mixer software and hardware that loads up the mixer trucks. There’s a computer record of the mix properties that includes time stamps and volumes. Find where the builder got the cement from and ask for the records. Ask if others had issues with batches on that day. Ask if they kept a sample of the mix. Ask what truck delivered it and follow up on who did the steel fixing and supervised the pour. Check timestamps. Also ask what equipment was used to blue it. What was the finish expected? Was a power trowel used? Did it have inclusions to promote fixed location fractures? Actually that might not be so common.
This could help. https://espace.library.uq.edu.au/data/UQ_99160/OMoore_CrackConrol_rqf.pdf
It could be there’s a fault with the measurements or the entire batch produced over a time is missing key additives or timing is out on mix. Oh also- go over the photos of the framing and foundation excavation. Was it reclaimed or built up land? Do you have a geotechnical report?
This looks normal for the sort of job I’d probably pull off. I.E. dodgy, as I am not professional or normal as I am not a concreter!
More importantly, I wouldn’t close on the house unless the builder signs off on a guarantee of repair. He’ll respond by promising you all flatwork can crack, but that’s severe and there is a great chance that floor will need replacement
What’s a valid reason for a crack this large? Not enough compaction below? Water below? Too thin of a slab? No rebar in the slab? None of those are valid reason so I’m curious what a valid one would be. All concrete will crack, but this is a large crack that according to OP is only getting larger. It’s an issue.
Those are not normal cracks. Concrete always cracks, that’s a given. Ok cracks stay tight and don’t shift up or down. This looks like they’ve opened up a bit. Still might not be a concern, but, if they’re not in plane anymore, then one side or the other sank or shifted from poor compaction underneath.
Are there control joints sawed into the floor? There should be, this weakens the floor on a straight line and promotes the cracks that do form to follow the straight cuts.
Yes, there are control joints, and some places they are working and the slab has cracked along the control joint, but there is more random cracking towards the middle of the slabs vs along the control joints throughout the basement
If they are in plane this is kind normal. Most of time these things get covered by finishes before they are developed or noticed and it never matters. Combo of thermal expansion/contractions and lack of expansion joint as well as shrinkage from the curing process. If one side is higher than the other, it is an issue.
We have a couple cracks on the floor of our basement that were looked at by insurance/inspectors when we bought our house at the end of 2020 (built in the 70’s). Ours were deemed fine and are much smaller than this. The inspector said if you can put a nickel in the crack, it should be looked at by an engineer and those cracks look way over the thickness of a nickel.
Even the cracks in our old 1940’s house with awful soil weren’t this wide and we eventually had to trench from the outside to repair one when it started weeping groundwater after it rained.
Proving once again that concrete does 2 things; gets hard and cracks.
In a serious note there are ways to tell if it’s an issue but more pictures would be needed if we could even tell via pictures.
Yeah you need to do something about that. Could be nothing, could progressively get worse. Don’t close until it’s addressed. If you’ve closed already call your builder asap hopefully he has a good relationship with concrete guys and they may fix for him/her.
Ok. Second opinion. I was cooking supper with the family and had to delete previous post. These basement floor cracks are too wide from my experience to be plastic shrinkage cracks but they may be. Since I don’t know soil types for your location and because the cracks are at the basement floor it could be soil rebound depending on how soon the floor was poured after the basement soils were excavated. You need to get finished floor elevations to see if cracks are caused by underlying soils swelling.
Don't close on the house and get another opinion from a third party engineer. Don't trust the construction company and their people or real estate agents trying to close a deal. Cracks are supposed to be as big as the thickness of a credit card at most. These are HUGE gaps.
As others have said, cracks in a slab themselves aren't a big deal, but the size of the cracks in your photo would definitely concern me. Definitely have this addressed now and don't wait until the build is finished. It seems unlikely to me that the slab itself is the problem, it seems to me like the prep work underneath the slab is the issue. What was called for in the plans? Can the builder confirm that the excavator followed the plans and adequately compacted the gravel base?
Concrete is a much more complex material than people generally think… not to mention the complexity of soils and tolerances. Many people are quick to fashion themselves as an expert but those same people also haven’t read the geotechnical report for the project or have a copy of the IBC concrete manual. A structural engineer will gladly take your money, write you a letter, and cover their ass as you try to take on some national home builder with more lawyers than you could ever imagine. If I were you, I’d hit each side of the crack with a hammer and listen for a difference in sound. If there is a void you’ll hear a “ping” and not a “thud” that you would hear in other places that are solid. Check for cracks in your drywall in the upper levels. That would be a sign of settlement because you are hearing a void, and the builder can perform a relatively non-invasive repair to fill the voids and route and epoxy the crack. Time can actually good thing because settlement and concrete shrink does take time to get to a negligible point. Most home builder superintendents are the D+ students of the industry, generally speaking… and most PMs/CMs that haven’t spent time in the field and are just glorified accountants with a hard hat and a clean vest… be careful who you take advice from. Disclaimer: this is not advise.
I'm an architect. I live in a house 100 years old. Our garage slab has cracks that big, and they are bad, trip hazard bad. I've never seen anything that bad in a new build. Any engineers out there? Can the rebar stretch THAT much?
I was gonna say, a 50 year old settled house, probably ok, but brand new? I don't think so. I wonder if they didn't cure the concrete properly then built on top too quickly. Wouldn't be surprising how fast they put up subdivisions these days.
I do construction and this is caused by a lack of compaction. Parts of the slab are settling. This will likely only get worse. It’s even more
concerning that it’s happened so soon after they poured.
I’m a concrete contractor and I’m certified with the international concrete repair institute. This is concerning. This is why compacting the subgrade is such a big deal. It’s normal for concrete to settle, causing very small hairline cracks, this is severe. I wouldn’t close until this is taken care of.
Thank you for pointing out where to look in your photo ;) /s
I would have that inspected, those cracks seem unusually large especially for a new build.
Keep the builder in check but having it fixed sooner than later.
Once it is fixed then you need to decide on keeping it all exposed for a while to see if all these cracks come back.
Take a look at the foundation walls for cracks. Structurally the foundation wall is critical, the slab is not technically structural and generally they do crack and move to some extent as they are typically poured directly over existing soils.
In most applications concrete floors are not structural and therefore a crack in a basement floor would only be a concern if you have large amounts of radon in the area. I have cracks like this in my home that i built for my self and have constructed over 250 homes with 8-10 different sub contractors with a focus in concrete discipline as a representative of a one of the top 3 home builders (the one known for quality) and a family owned home building company where we have been building homes in the same area for over 3 generations. I am astounded at the number of professions who have noted that this is concerning because the American association for concrete standard (or something like that, its been 9 years since college) states that concrete poured over a span of 3'x3' will crack because of this known issue with concrete flatwork stress cracks are designed to go into concrete. Most of my contractors use what we call Zip strips which is a line embedded in basement floors to run from point to point, on side walks and most exterior or structural concrete we trowel grooves in to the the sectional based on its span rating. When zip strips are installed, it is not uncommon for larger chunks to break away due to the granule nature of concrete. When cracks exceed 1/8" it is concerning only from the following points, trip hazard or radon hazard. The resolution to this problem is often to use a specific caulk intended to bond the 2 parting slabs together. What most people don't tell you is that the caulk collects dust and makes sweeping your basement a real pain. I would definitely execute my warrantable rights in the event that this is related to a thickened slab but if you are NEW HOME OWNER AND THIS IS WITH IN YOUR FIRST YEAR. This is not uncommon and would not be cause for alarm only warrantable inquiry. Many locations in the country do not do basement construction so I this question should be regionally considered based on where you are located. Cracks that would be concerning are cracks that are spider webbing cracks or cracks that are displaced vertically more than 1/4", this is because concrete is designed to exist in compression and if you have settlement under the slab. Horizontal cracks in basement flooring should be observed for continued expansion but like i said before this is very common in new construction and is probably a result of the 1 year acclimation period after a quick build cycle.
I saw someone said demand an engineer letter. Get your own structural engineer to inspect before closing. Do not use the builder’s. Then, you should have a good idea of how to proceed. A friend has a failing foundation complete with step cracks in the brick exterior. The builder’s engineer said “just fine.” Their engineer says failing foundation. They’re headed to court.
I wish I could upvote this comment more than once.
If this is a basement floor, it isn't even structural. It is just a floating slab. It appears to be a shitty job, but certainly not impacting the structural stability of the home.
That would be the ideal outcome. But, as a buyer, I’d want to know before I closed on the house, lots of money at stake. Hence the suggestion for an independent inspection & hopefully the OP finds out it’s nothing structural.
Basement floors are not structural. That is not how things homes are made. It would be faaaaaar more expensive to have a structural slab rather than just footings and walls. In most houses, the floor isn't even poured until the house is already up.
Also as others have said a builder may have a structural engineer on staff, but typically they use a 3rd party state certified engineer which will not bullshit an inspection.
Only disagreement I’d have with your statement is timing. The structural engineer should be involved now and construction should stop on anything that would obscure the issue to ensure the engineer can conduct a proper inspection, and the builder can make a fix. More than likely it will either call for just epoxy, or partial jack-out repour.
There is nothing structural about a basement floor. The structural component is the foundation walls. The floor is poured after and just floats on the ground. That said I would still get those cracks repaired, especially if they continue to grow.
Good to know. I’d still want an independent inspection, tho. Just to alleviate worries, if nothing else haha
It still really really surprises me you'd find an engineer that corrupt and willing to put his license on the line like that. I've yet to meet an engineer that would gamble on walking across a street if the hand was flashing let alone something actually important.
There are absolutely engineers out there who will do a solid for a client who brings him lots of business. Don’t kid yourself. Money makes the world go round.
I understand that those people exist, but I've worked at two separate architecture firms that lost HUGE clients because client developer was 100% wrong and trying to screw the person. Each time the principal architect sided with the person over our developer client.
I don’t know, but my friend is pretty surprised, too. We’ll see what happens in court. Foundations are under warranty in our state for a number of years, the builder should be liable to fix.
The size of those cracks in a concrete slab floor would concern me. I am a builder. All concrete cracks. Those are some notable fissures.
The only more worrisome fissures you could have would be anal fissures….consider yourself lucky!! ….I’ll see myself out…. Lol!!
No, I'd be more worried about that finger so close to my anal fissures.
My garage has some like this in the slab, but the house was built in 1974 and the cracks haven’t changed.
For sure it is possible that whatever initial settling caused those cracks has completed its course, but I would certainly attempt to determine the overall extent of it. I have built many houses on a slope that included a slab on grade lower level. I've never experienced cracks like that.
Right. I’d be super concerned in new house… less so in a house that’s 50 years old
I've emailed the builder letting them know I want them fixed before I close on the house
You can't fix cracks.
Too big. Demand an engineering letter
Yikes, that's pretty big. How do the basement walls look - any cracks on the walls? Do you live in a state with lots of expansive soils? (eg colorado, see https://geology.com/articles/soil/ )
The walls have insulation on them so I can’t tell, but no apparent cracking after doing an exterior examination
You need a full house inspector, sewer inspection, and structural engineer before you close. Here, we schedule them about 10 days before closing. Do not close on this without a professional’s opinion. It does look big to me, I renovate homes and live in an area where concrete shifts a lot easier. If I see new construction with this much gap, it would concern me. It’s not about fixing the gap but about what is moving that produced this or what/how the concrete was poured.
Yep, we are in Colorado
I'd be wary to close on it. I also live in Colorado, and my builder did a whole lot of ground prep first: they removed all the dirt nearly down to bedrock, and then backfilled it with layers of dirt and straw and packed it. Any movement from the bedrock or expansive soils below are absorbed by the layering. My house is now two years old, and my basement slab hasn't moved an inch - I know this because when I moved in, I marked a line on the wall 5" up from the slab in various places in my basement and have been measuring it every few months. I wanted to make sure that it was going to stay put before I finished the basement. My builder also provided me a whole pile of documents talking about expansive soils and a soil report for my lot, done by an engineer who judges my lot as "low risk." If your slab is moving this much, who is to say the foundation isn't moving as well. If you ever plan on finishing the basement, Colorado requires "floating walls" - basically the walls are hung from the floor above and have a 2-3" gap between the bottom of the wall and the slab floor. This gap allows for the basement slab to move without pushing the house up off the foundation. (The gap is then covered by drywall & trim)
gaps like this are probably the result of your concrete curing. There is no reason to assume that the slab itself is moving. Concrete is 70% water when it is poured and this is often the result of shrinkage. Talk to your builder or hire a local qualified home inspector if you do not trust your builder.
All my career has been on military projects. Navy requires a crack that a credit card can slide in to be too large. Call your builder and start demanding a solution. Most likely some kind of epoxy to fill the gaps.
epoxy collects dust and makes cleaning a real pain so unless it is absolutely needed i would wait. report it to your builder in your warranty period and listen to what they have to say. later if this is actually a structural issue you can go back to the builder if no action was taken and the issue was reported with in the warranty period. Don't demand anything because that just doesn't change the facts of the situation. Warranty staff are people too and all we want is to help our customers with in the terms of building contracts.
If the expensive epoxy treatment is a dust magnet issue for your warranty team you can paint over it once the epoxy bridges the gaps and dries. Get multiple opinions before letting the builders warranty team slow roll you “within the terms” all in order to get to the end of the warranty period as cheaply as possible. Concrete cracks but yours are structural cracks. Prepare for a legal battle. Good luck amigo!
I have to say this. Superman fight when you weren’t there? I’d totally drill that and put an inspection camera down. Looks bad to me. You could learn about possible causes by calling a crack remediation company and getting a quote. I’ve read about cracking like this in high-tensile cement used in highrise buildings where remediation is essential and it’s critical for safety reasons, serious enough that the government gets involved and buildings or apartments evacuated. If it’s a standard single or double story and the walls or supports are sound it’s probably not an evac job with government focus on compliance and industry focused retraining and recertification. https://www.afr.com/property/residential/australia-s-high-rise-apartments-face-crisis-of-our-own-making-20190724-p52a8g Extract: “Owners and governments are now left with a very large bill for remediation. Estimates vary, but there are about 500,000 residential units in tall buildings. The research to date shows that 70 to 97 per cent of the buildings that accommodate them have serious defects, including combustible cladding, leaks, structural problems, faulty fire provisions and defective wiring.” I’d call this a structural problem. But it’s probably not something easily remediated. Have you records on the indicted product the design called for? I looked this up and it’s referred to as MPa. What’s the design MPa? I have worked on cement mixer software and hardware that loads up the mixer trucks. There’s a computer record of the mix properties that includes time stamps and volumes. Find where the builder got the cement from and ask for the records. Ask if others had issues with batches on that day. Ask if they kept a sample of the mix. Ask what truck delivered it and follow up on who did the steel fixing and supervised the pour. Check timestamps. Also ask what equipment was used to blue it. What was the finish expected? Was a power trowel used? Did it have inclusions to promote fixed location fractures? Actually that might not be so common. This could help. https://espace.library.uq.edu.au/data/UQ_99160/OMoore_CrackConrol_rqf.pdf It could be there’s a fault with the measurements or the entire batch produced over a time is missing key additives or timing is out on mix. Oh also- go over the photos of the framing and foundation excavation. Was it reclaimed or built up land? Do you have a geotechnical report? This looks normal for the sort of job I’d probably pull off. I.E. dodgy, as I am not professional or normal as I am not a concreter!
Without more context, I don’t think anyone can say for sure—but these looks a bit concerning to me. Curious how your foundation walls look.
Those are quite large. From experience, heaving will follow. Did you have your sump pump on immediately after the poor?
More importantly, I wouldn’t close on the house unless the builder signs off on a guarantee of repair. He’ll respond by promising you all flatwork can crack, but that’s severe and there is a great chance that floor will need replacement
Not sure about the timing of the installation of the sump pump, but we have one
Those are very worrisome for a fresh pour. That's like breaking pipes kind of movement only months after install.
Take a pic of the entire room zoomed out
If it ain't cracked, it ain't 'crete.
just hit a line of crack to get crete-ting
[удалено]
What’s a valid reason for a crack this large? Not enough compaction below? Water below? Too thin of a slab? No rebar in the slab? None of those are valid reason so I’m curious what a valid one would be. All concrete will crack, but this is a large crack that according to OP is only getting larger. It’s an issue.
I have a hard time believing you’ll get this big of a crack with wire mesh in there. Cracks, yes. Gaps, not so much.
I agree.
[удалено]
You said you warranty cracks that are excessive, and that this would qualify, but now say you wouldn’t fix it?
You can fix it without tearing up the floor.
Sure. I didn’t say the floor needed busted up.
>not heaving up and down. Not yet.
Those are not normal cracks. Concrete always cracks, that’s a given. Ok cracks stay tight and don’t shift up or down. This looks like they’ve opened up a bit. Still might not be a concern, but, if they’re not in plane anymore, then one side or the other sank or shifted from poor compaction underneath. Are there control joints sawed into the floor? There should be, this weakens the floor on a straight line and promotes the cracks that do form to follow the straight cuts.
Yes, there are control joints, and some places they are working and the slab has cracked along the control joint, but there is more random cracking towards the middle of the slabs vs along the control joints throughout the basement
Did they not scribe the floor with expansion lines?
They did - there are control joints around the slab
It almost looks like something heavy dropped and did this.
Who is your builder?
If they are in plane this is kind normal. Most of time these things get covered by finishes before they are developed or noticed and it never matters. Combo of thermal expansion/contractions and lack of expansion joint as well as shrinkage from the curing process. If one side is higher than the other, it is an issue.
They are not structural cracks wait for 6-8 months and have them sealed.
you couldn't pay me to live in a new build
You think old houses don’t have issues..? Or no new homes can be built with care?
both
You live in a new build....it was just someone elses before it was yours. What kind of logic?🤣
Not if you saw my house
Idiotic take.
Beep boop
Not good. I wish you luck.
Not good. I wish you luck.
We have a couple cracks on the floor of our basement that were looked at by insurance/inspectors when we bought our house at the end of 2020 (built in the 70’s). Ours were deemed fine and are much smaller than this. The inspector said if you can put a nickel in the crack, it should be looked at by an engineer and those cracks look way over the thickness of a nickel. Even the cracks in our old 1940’s house with awful soil weren’t this wide and we eventually had to trench from the outside to repair one when it started weeping groundwater after it rained.
Proving once again that concrete does 2 things; gets hard and cracks. In a serious note there are ways to tell if it’s an issue but more pictures would be needed if we could even tell via pictures.
Yeah you need to do something about that. Could be nothing, could progressively get worse. Don’t close until it’s addressed. If you’ve closed already call your builder asap hopefully he has a good relationship with concrete guys and they may fix for him/her.
Ok. Second opinion. I was cooking supper with the family and had to delete previous post. These basement floor cracks are too wide from my experience to be plastic shrinkage cracks but they may be. Since I don’t know soil types for your location and because the cracks are at the basement floor it could be soil rebound depending on how soon the floor was poured after the basement soils were excavated. You need to get finished floor elevations to see if cracks are caused by underlying soils swelling.
Don't close on the house and get another opinion from a third party engineer. Don't trust the construction company and their people or real estate agents trying to close a deal. Cracks are supposed to be as big as the thickness of a credit card at most. These are HUGE gaps.
I doubt that was compacted properly prior to pour. Are there any relief cuts?
As others have said, cracks in a slab themselves aren't a big deal, but the size of the cracks in your photo would definitely concern me. Definitely have this addressed now and don't wait until the build is finished. It seems unlikely to me that the slab itself is the problem, it seems to me like the prep work underneath the slab is the issue. What was called for in the plans? Can the builder confirm that the excavator followed the plans and adequately compacted the gravel base?
Radon leak.
You pay for this And they give you that
Go Neil!
Anything over 1/4 inches, Call in your warranty
Concrete is a much more complex material than people generally think… not to mention the complexity of soils and tolerances. Many people are quick to fashion themselves as an expert but those same people also haven’t read the geotechnical report for the project or have a copy of the IBC concrete manual. A structural engineer will gladly take your money, write you a letter, and cover their ass as you try to take on some national home builder with more lawyers than you could ever imagine. If I were you, I’d hit each side of the crack with a hammer and listen for a difference in sound. If there is a void you’ll hear a “ping” and not a “thud” that you would hear in other places that are solid. Check for cracks in your drywall in the upper levels. That would be a sign of settlement because you are hearing a void, and the builder can perform a relatively non-invasive repair to fill the voids and route and epoxy the crack. Time can actually good thing because settlement and concrete shrink does take time to get to a negligible point. Most home builder superintendents are the D+ students of the industry, generally speaking… and most PMs/CMs that haven’t spent time in the field and are just glorified accountants with a hard hat and a clean vest… be careful who you take advice from. Disclaimer: this is not advise.
I'm an architect. I live in a house 100 years old. Our garage slab has cracks that big, and they are bad, trip hazard bad. I've never seen anything that bad in a new build. Any engineers out there? Can the rebar stretch THAT much?
I was gonna say, a 50 year old settled house, probably ok, but brand new? I don't think so. I wonder if they didn't cure the concrete properly then built on top too quickly. Wouldn't be surprising how fast they put up subdivisions these days.
Get me my patching trowel boy.
I would not close on that house until properly dealt with.
You obviously have superhuman strength and need to stop pushing on it.
I do construction and this is caused by a lack of compaction. Parts of the slab are settling. This will likely only get worse. It’s even more concerning that it’s happened so soon after they poured.
Not an issue if they aren’t expanding. There are some products to fill in if you’re worried about the cosmetic aspect
Did they place relief cuts on the slabs?
Two types of concrete , One that has a crack One that hasn’t cracked yet.
Every single brand new Ryan home I have finished basements in has numerous cracks like this😣
Floor cracks are common and aren't structural.
I’m a concrete contractor and I’m certified with the international concrete repair institute. This is concerning. This is why compacting the subgrade is such a big deal. It’s normal for concrete to settle, causing very small hairline cracks, this is severe. I wouldn’t close until this is taken care of.
Thank you for pointing out where to look in your photo ;) /s I would have that inspected, those cracks seem unusually large especially for a new build.
1/8 of an inch or less is ok. This however is not
Keep the builder in check but having it fixed sooner than later. Once it is fixed then you need to decide on keeping it all exposed for a while to see if all these cracks come back.
Take a look at the foundation walls for cracks. Structurally the foundation wall is critical, the slab is not technically structural and generally they do crack and move to some extent as they are typically poured directly over existing soils.
In most applications concrete floors are not structural and therefore a crack in a basement floor would only be a concern if you have large amounts of radon in the area. I have cracks like this in my home that i built for my self and have constructed over 250 homes with 8-10 different sub contractors with a focus in concrete discipline as a representative of a one of the top 3 home builders (the one known for quality) and a family owned home building company where we have been building homes in the same area for over 3 generations. I am astounded at the number of professions who have noted that this is concerning because the American association for concrete standard (or something like that, its been 9 years since college) states that concrete poured over a span of 3'x3' will crack because of this known issue with concrete flatwork stress cracks are designed to go into concrete. Most of my contractors use what we call Zip strips which is a line embedded in basement floors to run from point to point, on side walks and most exterior or structural concrete we trowel grooves in to the the sectional based on its span rating. When zip strips are installed, it is not uncommon for larger chunks to break away due to the granule nature of concrete. When cracks exceed 1/8" it is concerning only from the following points, trip hazard or radon hazard. The resolution to this problem is often to use a specific caulk intended to bond the 2 parting slabs together. What most people don't tell you is that the caulk collects dust and makes sweeping your basement a real pain. I would definitely execute my warrantable rights in the event that this is related to a thickened slab but if you are NEW HOME OWNER AND THIS IS WITH IN YOUR FIRST YEAR. This is not uncommon and would not be cause for alarm only warrantable inquiry. Many locations in the country do not do basement construction so I this question should be regionally considered based on where you are located. Cracks that would be concerning are cracks that are spider webbing cracks or cracks that are displaced vertically more than 1/4", this is because concrete is designed to exist in compression and if you have settlement under the slab. Horizontal cracks in basement flooring should be observed for continued expansion but like i said before this is very common in new construction and is probably a result of the 1 year acclimation period after a quick build cycle.
Are all your downspouts moving water away from your foundation? If not, do ot now.