PDA

View Full Version : Pitted concrete



Bob Rufener
08-20-2010, 4:13 PM
We have lived in hour home for almost 35 years. Our concrete slab in front of the garage has a few smaller cracks but one slab has lots of pitting on the surface. We have heard that concrete can be resurfaced without replacing the entire slab. Has anyone had any experience and does it hold up over time? We live in SE Wisconsin and temps range from highs in the 90's in the summer to ungodly cold in the winter. Thanks for any help.

David G Baker
08-21-2010, 3:36 PM
Can't help on the capping recommendation but the pitting is probably from road salt. I have some of it but I do not leave my vehicles parked on the slab. I have a few cracks and I keep them filled with a rubber type product designed for concrete. The filler keeps the freeze/thaw from making the cracks larger.
I go to a home show once in a while and I have seen demonstrations that show a process for capping older concrete with around 3/4" of some product but it has always been used indoors. There may be a similar product designed for exterior slabs but I have not seen it.

Russ Filtz
08-22-2010, 5:05 PM
You always run the risk of delamination failures with fixes. And all the prep work will be key to prevent it. Can be a dirty nasty job to depending on how it's done. Depending on the total area and slab thickness, I'd say re-pour the whole mess.

Judd Owens
08-23-2010, 9:36 PM
You're looking at bushing the concrete over the entire surface if you're going to pour the 1" cap. That is, roughing it up to an amplitude of 1/4"...on all of it. Unless you have an industrial machine, or could rent one reasonable, that will take a long time with a small chipping hammer. Also, you have to get it very clean afterwards, for the bonding agent to do its job. The bonding agent is another thing that you don't want to skimp on. It helps bond the new to the old. How old is the concrete in question? Does it have any type of re-enforcement? Rebars or wire mesh, etc... If it's re-enforced, I would go with the capping method, but don't skimp. If it's not, I would prob. just tear it out and start fresh, putting a joint in with expansion material at the last spot where the concrete is still good, squared across.

Dave Lehnert
08-23-2010, 10:55 PM
No experience but is on my list of things to do.

http://www.quikrete.com/PDFs/Projects/RepairingBadlyPittedAndChippedConcrete.pdf

Bret Duffin
08-23-2010, 11:15 PM
I hate to admit it but I have experience in this matter.

If there is no rebar or wire mesh in the slab and is only 4" thick or so, then it will break up fairly easily with a sledge hammer. Remove the slab and use the pieces that come out to build a garden wall then pour a new slab.

It's the real right way to do it. Patches don't work and look bad and will fail especially if the original damage was from salt, which never goes away.

Oh, if the concrete is re-enforced it will just be more work to remove but can be done in which case you might consider renting a jack hammer or hiring a backhoe depending on how big the slab is.

Good luck, Bret

Joe Chritz
08-24-2010, 12:04 PM
You should be able to rent or hire someone to do the dismantle relatively cheap. A skid steer or bobcat with a concrete hammer will destroy a normal size approach in about 20 minutes.

Caps may work but the cost and effort make them normally a bad idea for outdoor slabs.

Joe

Steve Costa
08-27-2010, 7:43 PM
Regardless of how you choose to solve the problem invest in a quality concrete sealer. Euclid Chemical Co. makes a product called "Diamond Clear" in 2 versions. One is a flat sheen the other is glossy. I apply the sealer every 2 or 3 yrs.

I live at 8200' in So West Colorado where we get 4' to 6' of snow a year and temperatures range between 20F & -20F in the winter (not very cold by your standards, but cold enoug for me:(). I have used the above sealer on my concrete for the last 8 years (we don't use road salt in this part of the country) and the concrete is holding up very nicely.

Steve

Bob Rufener
08-28-2010, 11:16 PM
I heed your recommendations. I found a local guy who seems like a very straight shooter. We are opting for replacement of the slab and also a small sidewalk that has sunk about 2-3" since it was poured 34 years ago. He also does concrete designs in different patterns so we may opt for that option. I'll post results when it is done. Thanks for the input.

John alder
08-31-2010, 1:03 PM
I have used "top and Bond" on a patio with good results.My home depot carries it.