I am building a new house and have noticed a crack that has developed in the basement floor. The crack extends from a outside corner to the wall opposite of it.
The width of the crack is a dime to nickel.
If I plan to sell the house how can I correct this problem? Should I be concerned about this crack? Is this a normal occurence?
I appreciate any suggestions.
Replies
IMHO that is a significant crack, especially for new construction.
Since it is gapped, it indicates that either the area along the crack has risen, or one or more sides has settled. Why that has happened???....maybe a structural PE would be worth the $$....pumping or jacking may be indicated.
One can expect some cracks....hairline in nature ....in any basement floor, but not the size of those in your desciption.
I would recomend monitoring the crack for continued changes, before attempting any repair. Mark and measure at increments along the crack, record and check periodically. All repairs will be obvious, but repeated repairs will indicate continued movement.
When was the basement poured? What is your weather/seasonal conditions?
Was the basement left open to weather over the winter?
Is there a water problem...hydraulic jacking by standing water levels!
What kind of and how much fill was used in the floor design?
Were the footings excavated to "terra firma"?
Just lots of why's..................Iron Helix
There is a sump pump and the pit has been dry for the entire time the floor was in.
The house is still under construction but the basement was closed in before the floor went in. The furnace is not running so the basement is not heated. Could it be the temperature? Is this something the concrete contractor should address?
The bottom line is the house needs to be sold and I see this crack as a major problem. Is this true?
First...let me tell you that from what I read from your description for the "crack"...it starts at one corner and goes all the way across the floor and ends at the opposite wall. It is a long crack, splitting the basement floor into two large sections.
If this is correct..... I would consider it a significant indicator of settlement, and if I was to inspect this house prior to sale I would advise my client to seek out the services of a structural engineer to assess why there is such a crack in a new house.
If I was a potential buyer, and saw that crack, and know what I know, I would thank you for your time and walk out the door.
If the crack is as in paragraph "one"...then I would call back the basement contractor, and would consider it a major problem in closing a sale.
If my understanding of the "crack" is different than paragraph "one" then I need the description clarified so I can start over with my considerations/opinions.
Temperature is probably not a consideration....unless you live in a very cold climate.
Is it a walk out basement?
Are there any frost footings involved?
What is the basement dimensions and configuration?
What are the specifications on the floor pour?
What about the wall footing specifications?
How tall & thick are the basement walls?
Was rebar used in the walls, and remesh & vapor barrier in the floor?
Was the basement backfilled prior to installation of the floor system?
.....................Iron Helix
All I have to say is...you should be blaming the builder before you go to the concrete guy. This sounds like a problem that the Excavator half-assed and he and the builder need to figure it out. The concrete guy just pours the concrete, unless of course he skimped the concrete in spots or didn't use rebar to save a buck or two. After he leaves it shouldn't be his problem.
Locally the builders sub concrete basements.
Half of the basement subs do their own excavation, the other half expect the builder to supply the excavation sub.
Most of the basement dudes sub the flatwork.
Definitely would not go after the "flatwork man".....he had nothing to do with the excavation and footing prep....but the basement man and or the builder had a hand in the execution of the footings and fill.
I would ask the builder and basement sub for their opinion about the "crack"...being careful not to be accusatory....just collect the info and watch the body lanquage.
Then "buy" an unbiased opinion from a professional.....building inspector, architect, structural engineer....see how that compares to the builders opinion, and go from there.
If there was a construction error the builder and his subs may be responsible.
If there was an "unknown" in the site's soils then there will be a battle.
If it is settling there are some remedies available that should be applied now before there is further settling.
No matter the outcome it is still your house and you need to have a marketable product or you will suffer the losses. Collect the facts, address the resolution, document it all and move on toward the sale.
Standing still will only cost you more money.
...................Iron Helix
I agree with Mr Helix. Anything more than the width of a sharp pencil is a problem. If you can drop a nickle in, you've got a problem.
Any visible cracks in the exterior of the house? Any doors that don't close properly, or show uneven gaps between the door and frame?
You might want to call a local structural engineer, maybe even the one who did the plans for the house, and ask what they would charge for a site visit and verbal report. He might say it looks ok, or he might recommend an in-depth exam.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
Before you go off half cocked, try to determine on your own what kind of crack that you have.
Use a four foot level and lay it across the crack at several places. If the average is fairly level across both halves then you probably have a shrinkage crack. If the level shows a gap at the crack line then you may have a settlement problem and if the level rides high at the crack line then you may have a heaving problem.
Let me know what you find out.
Gabe
I talked to the concrete sub and he also suggested placing a level across the crack. I did this and found both sides to be even. The sub also suggested to wait and see if the crack opens further. If no further expansion occurs he recommends mixing some cement and filling the crack and try blending the top. He also mention that sometimes as things dry out the crack may close slightly. Another suggestion was to cut the crack and treat as an expansion joint(only after the crack has stopped expanding). His bottom line was to wait and see how the crack changes to determine the next step. He stated last resort would be to cut out a section of the floor and repour.
The basement has an L shape to it and the crack has developed off of the corner of the L. The distance between the corner and opposite wall is about 10 feet.
Any comments would be appreciated.
An L shaped slab should have been saw cut to control or direct the shrinkage cracking that normally occurs in that shape of slab. The inside corner acts like a wedge as the slab cures.
The crack in your slab appears to be cosmetic in nature and shouldn't cause any worry. Let it cure and fill with a two part caulking that is fluid enough to fill and seal the crack.
Gabe
I agree, the location is exactly where I would expect to find a shrinkage crack
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I'll see your "agree" and raise you two "concurs".
Work safe,
Gabe
most of the cracks that I have witness has been on corners or points. nealy 90% of them. this slab being a "L" should of been saw cut both ways. making three squares.( depending on size of course)
The key word being "squares"
Gabe
GABE made a good point, if the square are too big they will crack anyway. Thickness of slab effect it too. On a 4 inch slab I like my square no bigger than 10x10 and then I wil cut deep on 4 inches, I want at least 1 inch to 1 1/2 deep.
The concrete sub told me they normally don't make expansion cuts in basement floors. He stated the temperature differences don't exist like they do in a garage. I built a condo where I believe they made saw cuts at a couple of corners. Thanks for all the input.
Well the l-shaped footprint sure makes me eat a little crow......
I'll go with the rest on the split/crack being caused by differential shrinkage of the legs of the "L" . Common for that configuration! Should-a'-asked!
Sure a better result for the house and it's potential sale. Might want to document the sequence for a potential buyer's concerns about the "crack".
.................Iron Helix
I call your concours. Let's see the crack fill.The only other thing I had in mind as far as quality goes is that some flat finishers use too much water which increases the number and size of shrinkage cracks, but this one doesn't sound too bad a problem
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Thanks Gabe.
I concur, only too lazy to offer the same advice.
Sometimes I just like to watch and see if a sensible solution arises.
EricI Love A Hand That Meets My Own,
With A Hold That Causes Some Sensation.
Greetings,
I didn't know you were in construction. What's your trade? I thought that with the handle firebird that you were in automotive.
It takes less time to sawcut a floor than it takes to discuss a random crack afterwards with a disatisfied client.
Chat later
Gabe
I'm always cathin' flack for that handle. First time I signed in that's what I used. Typical of what I MIGHT choose for passwords and such. I used to be a gear head in my youth, always Pontiacs, so choosing model names for PW's make it easy on my feeble mind when I'm trying to figure out what password goes where.
Now that the entire internet knows all of my passwords...............I do residential remodeling. I try to stick with baths and kitchens, but I'll consider anything as long as the client is nice to me and offers me enough money to make me happy. Done alot of framing earlier, several complete homes and have settled into a comfortable crawl with my oldest son working by my side.
That's it in a tiny nutshell!
I'm recalling a basement I poured in cool damp weather, I didn't get home till 2am.
Aahhh, youth!
EricI Love A Hand That Meets My Own,
With A Hold That Causes Some Sensation.
my oldest son working by my side.
Now that's working with class.
Thanks for the info,
chat later
Gabe
In a large slab, this much of a crack may not be "significant". Concrete shrinks as it cures, and you can get cracks like this. Ideally the shrinkage would be divided between several cracks (this is why they make control joints), but if a large slab shrinks into two sections a crack on the order of 1/8" isn't particularly odd. If there are no other cracks of any significance, **and** if there is no vertical displacement of one side vs the other, then there's probably nothing wrong.
Certainly, the GC and concrete guy could have done more to control this -- adjust the mix, add fiber, add control joints, etc -- but the issue is more cosmetic than structural.