Problems with new concrete driveway
#1
02-23-12, 02:20 PM
Problems with new concrete driveway
Last July, I had a local company install a new concrete driveway for me. At first I was satisfied with their work, but over the last few weeks some problems have arisen. While I was shoveling snow a while ago, I noticed that not only has the driveway already cracked all the way across, but that the surface of the cement had started to form what looked like blisters across a wide area. I noticed that if I stepped hard on the cement in that area, it made a weird crunching noise.
I kept an eye on it for a week or two, and things have really gotten worse quickly. The blisters turned into pits, and now the surface of the cement over an area of about a foot square has shattered into smaller pieces, and the blistering/pitting that I first noticed seems to be spreading. Needless to say, I'm pretty unhappy.
The company told me that the driveway was guaranteed for a year, but I don't have that in writing (I know, stupid mistake...lesson learned). I called the company owner and told him what was going on. He says that it sounds like spalling caused by the salt that people put on sidewalks and roads for de-icing. We have never used salt on the driveway, and the affected area is on a part of the driveway that the car wouldn't usually be sitting on anyway (farther from the garage than we usually park it). It seems that he's basically trying to blame the problem on me for not sealing the driveway, which I didn't know was necessary. According to my reading on the Web, properly mixed and poured cement should last for years and be able to handle road salt.
I guess my question is, is the company owner right? Is this all my fault for not applying a sealer, or can I reasonably hold them to their guarantee and ask them to redo the work? I'm stressed out about this and don't know if I'm in the wrong or not.
I kept an eye on it for a week or two, and things have really gotten worse quickly. The blisters turned into pits, and now the surface of the cement over an area of about a foot square has shattered into smaller pieces, and the blistering/pitting that I first noticed seems to be spreading. Needless to say, I'm pretty unhappy.
The company told me that the driveway was guaranteed for a year, but I don't have that in writing (I know, stupid mistake...lesson learned). I called the company owner and told him what was going on. He says that it sounds like spalling caused by the salt that people put on sidewalks and roads for de-icing. We have never used salt on the driveway, and the affected area is on a part of the driveway that the car wouldn't usually be sitting on anyway (farther from the garage than we usually park it). It seems that he's basically trying to blame the problem on me for not sealing the driveway, which I didn't know was necessary. According to my reading on the Web, properly mixed and poured cement should last for years and be able to handle road salt.
I guess my question is, is the company owner right? Is this all my fault for not applying a sealer, or can I reasonably hold them to their guarantee and ask them to redo the work? I'm stressed out about this and don't know if I'm in the wrong or not.
Last edited by Merloki; 02-23-12 at 02:22 PM. Reason: spelling
#2
02-23-12, 03:40 PM
Salt and so-called "safe" de-icers can both destroy an unsealed concrete surface. If you read the fine print on the "safe" stuff, it says not to use it on unsealed concrete or concrete less than a year old. Yours was both. Did you use a "safe" de-icer? If not, is it possible that passing snow plows or salt trucks could have thrown something onto the area in question? In other words, is it fairly close to the street?
Even if no salt or de-icers were used, soft aggregate or "chert" in the concrete can absorb moisture, freeze, and cause popouts. Before they actually popped all the way out, they could resemble blisters. in my opinion, the concrete company should have either sealed it before they left the job, or advised you to do it.
As to the crack, did the company install crack control joints into the slab (either tooled in or sawed in)? If so, and they were properly spaced and placed, the concrete should have cracked in the joints. Joints should be no farther apart than about 10 feet in either direction, with the resulting sections being roughly square shaped, and should be 1/4 as deep as the slab is thick (1 inch deep on a 4 inch thick slab). There are multiple reasons for cracks, but sometimes concrete just cracks for unknown reasons that are no one's "fault".
I wrote a comprehensive article about causes for concrete cracks on another site, but this forum's moderators won't let me post a link to it because they consider it advertising. I'm sure you can find many similar articles by doing a google search.
Good luck with your driveway. I doubt that the company will honor their guarantee or that you could win a lawsuit over it.
Call the ready-mix company who supplied the concrete to look at/test it. Have them bring a copy of the batch ticket with them. The information contained therein could be looked at by a third-party professional and may shed some light on the problem.
One fix for it would be to overlay the entire surface, but unfortunately that costs money.
Even if no salt or de-icers were used, soft aggregate or "chert" in the concrete can absorb moisture, freeze, and cause popouts. Before they actually popped all the way out, they could resemble blisters. in my opinion, the concrete company should have either sealed it before they left the job, or advised you to do it.
As to the crack, did the company install crack control joints into the slab (either tooled in or sawed in)? If so, and they were properly spaced and placed, the concrete should have cracked in the joints. Joints should be no farther apart than about 10 feet in either direction, with the resulting sections being roughly square shaped, and should be 1/4 as deep as the slab is thick (1 inch deep on a 4 inch thick slab). There are multiple reasons for cracks, but sometimes concrete just cracks for unknown reasons that are no one's "fault".
I wrote a comprehensive article about causes for concrete cracks on another site, but this forum's moderators won't let me post a link to it because they consider it advertising. I'm sure you can find many similar articles by doing a google search.
Good luck with your driveway. I doubt that the company will honor their guarantee or that you could win a lawsuit over it.
Call the ready-mix company who supplied the concrete to look at/test it. Have them bring a copy of the batch ticket with them. The information contained therein could be looked at by a third-party professional and may shed some light on the problem.
One fix for it would be to overlay the entire surface, but unfortunately that costs money.
#3
02-23-12, 04:11 PM
We have not put any de-icing products of any kind on the driveway. So the only way that anything could have gotten on the cement is if it got on the car and then dripped off. The driveway is pretty long, and the damaged area is in the middle, about 10 feet away from the street, so I doubt anything could have splashed off passing traffic. It's also a few feet away from where the car usually sits when it's parked.
There are several crack-control joints in the driveway, about 8 feet apart. The crack is only a few inches away from one of them.
They actually did recommend sealing the driveway, but I don't know if I wasn't listening hard enough or if they were unclear. Somehow I got the impression that sealing was not really important and was done more to protect the concrete from cosmetic problems like oil stains and that kind of thing. And some of the reading I've done implies that sealing the concrete during the first year is bad because it needs to cure first. Obviously I don't know much of anything about it. Unfortunately it looks like this is one that I'm going to have to chalk up to experience.
There are several crack-control joints in the driveway, about 8 feet apart. The crack is only a few inches away from one of them.
They actually did recommend sealing the driveway, but I don't know if I wasn't listening hard enough or if they were unclear. Somehow I got the impression that sealing was not really important and was done more to protect the concrete from cosmetic problems like oil stains and that kind of thing. And some of the reading I've done implies that sealing the concrete during the first year is bad because it needs to cure first. Obviously I don't know much of anything about it. Unfortunately it looks like this is one that I'm going to have to chalk up to experience.
#4
02-23-12, 05:24 PM
It would have cured within about a month from the time it was poured.
I'd not write it off just yet. Call the ready mix company and see what they say. They should have a quality control guy whose job it is to come out and look at problems and troubleshoot them.
I'd not write it off just yet. Call the ready mix company and see what they say. They should have a quality control guy whose job it is to come out and look at problems and troubleshoot them.
#5
02-23-12, 06:29 PM
Member
You are in CO, but no mention of where regarding the specific location.
Check to see if the concrete was "air entrained" (a very cheap extra cost) because of the freeze/thaw durability improvement. Around here, the good ready-mix suppliers will usually refuse to supply concrete for a driveway and some patios unless it is 4000 psi and air entrained. They just prefer to leave the problems to bottom feeding suppliers. They found it was not worth the time and cost getting into problem jobs where they could be drawn in by contractors that MAY have had placement.timing problems.
some times the scaling of the surface could be due to placement and finishing, while soft or expansive aggregates usually are localized and much smaller. If it is a case of aggregates, then the concrete supplier can go back to the aggregate supplier (unless the concrete supplier is also the aggregate supplier/producer).
Check with the supplier to see the batch tickets and determine what was delivered. Usually a good supplier has controlled batching systems and keeps all batching records for certification and proof of what was used.
Dick
Check to see if the concrete was "air entrained" (a very cheap extra cost) because of the freeze/thaw durability improvement. Around here, the good ready-mix suppliers will usually refuse to supply concrete for a driveway and some patios unless it is 4000 psi and air entrained. They just prefer to leave the problems to bottom feeding suppliers. They found it was not worth the time and cost getting into problem jobs where they could be drawn in by contractors that MAY have had placement.timing problems.
some times the scaling of the surface could be due to placement and finishing, while soft or expansive aggregates usually are localized and much smaller. If it is a case of aggregates, then the concrete supplier can go back to the aggregate supplier (unless the concrete supplier is also the aggregate supplier/producer).
Check with the supplier to see the batch tickets and determine what was delivered. Usually a good supplier has controlled batching systems and keeps all batching records for certification and proof of what was used.
Dick
#6
02-24-12, 12:42 PM
Thanks for the advice everyone, I really appreciate it. I attached some pictures of the driveway.
I am in the Denver metro area. I don't recall asking or being told directly that the concrete was air entrained, but I think it was, because on their website they state that they use air entrained concrete. The company mixed the concrete on-site. An acquaintance has suggested to me that they may have mixed too much water to make it easier to work with. The weather on that day was very hot and I noticed that they seemed to add a bit of water while they were smoothing out the top of the cement after pouring it - I remember that there was what looked like standing water on the surface of the driveway that gradually dried up over several hours.
Here are links to the photos at Photobucket:
test008.jpg picture by Merloki - Photobucket
test010.jpg picture by Merloki - Photobucket
test011.jpg picture by Merloki - Photobucket
I am in the Denver metro area. I don't recall asking or being told directly that the concrete was air entrained, but I think it was, because on their website they state that they use air entrained concrete. The company mixed the concrete on-site. An acquaintance has suggested to me that they may have mixed too much water to make it easier to work with. The weather on that day was very hot and I noticed that they seemed to add a bit of water while they were smoothing out the top of the cement after pouring it - I remember that there was what looked like standing water on the surface of the driveway that gradually dried up over several hours.
Here are links to the photos at Photobucket:
test008.jpg picture by Merloki - Photobucket
test010.jpg picture by Merloki - Photobucket
test011.jpg picture by Merloki - Photobucket
Last edited by Merloki; 02-24-12 at 01:28 PM.
#7
02-24-12, 01:12 PM
Try this - http://www.doityourself.com/forum/el...-pictures.html
edit - disregard, for whatever reason the links weren't visible earlier
edit - disregard, for whatever reason the links weren't visible earlier
Last edited by marksr; 02-24-12 at 01:35 PM.
#9
02-24-12, 01:46 PM
Wow! That's a lot worse than I imagined. So the contractor mixed it themselves on site? I'm assuming with a volumetric mixer? In that case, you'll get no help from a ready-mix company.
It's not chert as I suspected. The rocks themselves are intact, it's the paste that has come loose.
You may have to have it tested by an independent company. They'll find out what's wrong. It could very well be too much water worked into the surface.
First I'd send these pics to the contractor and tell him you're going to make a YouTube video of it to post online. That should get his attention. No one needs bad publicity like that.
It's not chert as I suspected. The rocks themselves are intact, it's the paste that has come loose.
You may have to have it tested by an independent company. They'll find out what's wrong. It could very well be too much water worked into the surface.
First I'd send these pics to the contractor and tell him you're going to make a YouTube video of it to post online. That should get his attention. No one needs bad publicity like that.
#10
05-11-12, 07:54 AM
Concrete driveway
Hi,
I was a civil Engineer before retirement and was invoved with many construction projects.
Your pics indicate a poor concrete mix , placement , and protection during the cure in a hot environment. All are under the contractor's control.
Concrete mix should should never get added water during placement or finishing. The concrete cure is a chemical process & results in internal heat build-up. The slab should ideally be protected from direct sun exposure and kept damp (light spray during day) until sounding with a hammer returns a solid ping. This usually takes 7 - 10 days.
Personnally, I had concrete sidewalks & driveways placed about 20 yrs ago and never had a problem with & never "sealed' the slab and applied salt (safe & other) every snow/ice event (New York).
I would hope your contractor will honor the guarantee.
I was a civil Engineer before retirement and was invoved with many construction projects.
Your pics indicate a poor concrete mix , placement , and protection during the cure in a hot environment. All are under the contractor's control.
Concrete mix should should never get added water during placement or finishing. The concrete cure is a chemical process & results in internal heat build-up. The slab should ideally be protected from direct sun exposure and kept damp (light spray during day) until sounding with a hammer returns a solid ping. This usually takes 7 - 10 days.
Personnally, I had concrete sidewalks & driveways placed about 20 yrs ago and never had a problem with & never "sealed' the slab and applied salt (safe & other) every snow/ice event (New York).
I would hope your contractor will honor the guarantee.
