Cold joints in foundation walls

Cold joints in concrete foundation walls…

If it’s been around for a long time with no movement visible: Possible structural concern, consider qualified contactor evaluation.

If it’s recent construction: *May be a structural concern, consider qualified contactor evaluation. *

Any sign of movement: Structural concern, recommend … repair… qualified contactor… Structural Engineer?

What’s the cure for a cold joint? Cut that section out, install dowels and pour a new section?


I have been around a lot of concrete and I’ve yet to see anything which required replacement because of a cold joint in residential construction.

You have a particular photo in question, or is this just a general question.

Just a general question, Dale. I noticed the other day you mentioned… I think it was repair of a cold joint. I’m re-writing narratives and trying to figure out how to word things.

When I see rebar showing I tell them the same thing the structural engineer who works with me once in a while tells them.

“Clean the crack, epoxy the bar, and parge it”.

If there isn’t any steel showing, clean it and parge it, since it generally is just a cosmetic issue anyway.

I find a lot of stem walls with the bar hanging out the sides.

Thanks, Dale.
In the past, I’ve often not even mentioned it because I’ve never seen a problem resulting from it. Seems like an individual situation call to some extent.

I agree, cold joints in general are not a concern, exposed rebar on the other hand a big concern. Ever see what rusting rebar will do to the concrete?

POP goes the concrete!:shock:

I do the same as Mr Duffy.

As long as it’s not a horizontal cold joint about in the middle 1/3 of the wall height it’s usually not a huge issue. But any cold joint is another possible location for a foundation leak.

As far as repairs, patching/replacing weakened sections or epoxy pressure injection can be used depending on the circumstances.

JMO & 2-nickels … :wink:

Cold joint in a concrete wall, usually would mean that the layer lifts of the pour were exaggerated to the point where consolidation of the two layers is no longer permissible. This creates a weak link in water intrusions unless it is above grade.

If re-enforcement is sufficient to maintain the integrity of the wall as a unit, then there would be no alarm in the structural domain.
Cold joints can be avoided by better planning and co-ordination with the activities at hand. But if one should occur, more concentration should be enhanced with the vibrator at the time of the pour to consolidate the two layers as much as possible.
If a gap still is evident, patch it with grout paste. This will help in water sealing the joint and the exterior, if below grade, needs to be address as well.
Marcel :slight_smile: :slight_smile:

Kenton, cover your assets, but if you feel compelled to tell “them” what to do, suggest filling with non-shrink grout.

Never realized CYA was a double entendre. Real important one, too.

Cold joints happen. Like Marcel pointed out they can usually be mitigated with careful planning on the part of the contractor. I have come across a few situations where the cement truck got caught in an accident or traffic and couldn’t make a delivery on time. The remedy was to drive a series of 4’ rebar down into the concrete and make sure the joint was as shallow as possible. The rebar stopped the joint from slipping but did not address the issue of water penetration. With the new membranes available on the market to coat the outside of the foundation walls water penetration should not be an issue. Post construction remediation is a different thing. Dig it up, install waterproofing and backfill. I know, big bucks.

Waterproofing the inside of the wall/joint would still raise moisture levels within the wall but might be an alternative for someone without big bucks.

This is off-thread, but contributes to the understanding of the problem.

You might think it is off topic, but I don’t think it is and welcome your views on the topic, because it all relates to one another.

I am not a fan at all on trying to resolve water intrusion on foundation work from the inside. Water intrusions from instances as a cold joint should be addressed before the foundation is backfilled and identified as a problem by the builder.
The problem is that a foundation Contractor will come in and do his thing, and the one that follows can not identify the problem, so it gets buried and the problem begins. What does that tell us.??? To me it means more education, co-ordinated efforts, and quality control on the General Contractor that is to oversee the project to begin with and prevent these problematic scenarios.

Unfortunately, like Larry E. quoted, it will cost some money to do it from the outside, but, that is the only proper way to do it. Anything different to that is just a patch to buy time before it all starts up again.

I would note it as I see it and recommend a reputable foundation Contractor to assess your concern of the water intrusions if existing, or potential there of.

I would not recommend a waterproofing Contractor, due the fact they all sell something different and could cost even more money for something that has not been proven for the past 30 years or so. IMHO.

Some one Reputable would be a Contractor that is well familiar with foundations and it’s waterproofing requirements for that particular area.

We can not and should not attempt to lead the blind to the blind. It makes quite an elaborate mess. Therefore, we should be carefull as to who we recommend in finding the proper fix or repairs required.

Hope this helps.

Marcel :slight_smile: :slight_smile:

I think one of the bigger issues with cold joints is usually it’s a typical location for water penetration (as long as it’s not straight across a wall in the middle 1/3).

Just parging or surface patching only helps that issue on a very temporary basis in my experience … like a band aid. Water leaks tend to pop out the patches fairly quickly. Epoxy or urethane injection is a much better option usually (depending on exact circumstances), although it is more expensive that just band-aid patching.

JMO & 2-nickels … :wink:

Hi. Robert;

Regarding cold joints, I would believe since we are talking about Residential Buildings, is somewhat a horse of a different color as far as Design, Performance , Execution, and Quality.
You as an Engineer and me as a Commercial Builder, both know that the Control of a Residential Concrete pour is unsupervised by any of the normally expected Quality Control that we might be accustomed to seeing.

Residential Concrete Contractors as I have observed Locally and endorsed by the Concrete Supplier Drivers, typically pour concrete at about a 6-7" slump and minimize the amount of ramps they have to build to back up the trucks so they do not have to pay for a Concrete Pump. For me using a concrete Pump is a no brainier.
Considering the slump of concrete that is being used, you now have a pour line in the finished product that is visible to the HI when inspecting the basement. Yep., it is horizontal or close to it.

The slope of the pour line can mathematically be estimated as to what slump was used. If an uncoordinated effort was made to the delivery of the concrete this pour line now becomes a cold joint.
Residential Contractors usually only have one vibrator with no spare and the 1 &1/2" vibrator head they have will not cut it when it comes to cold joints. With no performance or concrete specification that most have, vibration is probably in excess to what they would do.

Forms are stripped the next day and reveal an unconsolidated pour line with exposed aggregate and an entrance gate for water from the outside.

The type of Band Aid as you call it, I call the Bituthane 4000 Manufactured by Grace. They should not attempt to rely on the most common foundation coating that I have commonly observed.

This system has worked for me for years on end and don’t have to worry to much about the crappy backfill that usually occours with the local Residential Builders., other than the frost affect and the foundation it’self. In my case it is usually stone. Maybe I should say pea stone and sound like by buddy. ha. ha.

Bottom line is that it has to be addressed from the origin point and not with sophisticated products that cost an arm an a leg and not really a guarantee either.

Cost Estimates would be prudent at that point and the client or owner can make the final decision as to what is more economical at that point.

I would persue making the proper recommendations to a client as to who in the areas would be more educationally and qualified to make the necessary repairs.

I have said enough I guess. ha. ha.

Thanks for all the good contributions you have made. It is well appreciated.

:slight_smile: :slight_smile:



Dont get me wrong, I think good waterproof foundation coatings can be very useful for controlling moisture penetration. However over time they deteriorate, and don’t work well for crack or cold joint repairs based on my experience inspecting foundations that have older types of these coatings.

The problem is they are not good at bridging cracks or bad cold joints which essentially acts like cracks, since it’s often a weakened plane where shrinkage occurs that creates essentially a shrinkage crack. Over time they usually leak.

And the bottom line is cracks leak. Seen it on many foundations.


How is epoxy injected into a horizontal (more or less) crack so that it seals against moisture intrusion?

How? By a foundation repair professional. Okay, so that’s not the answer you want, probably. Darn margaritas, Jeopardy, and CSI-SVU. :margarit:

It’s done all the time around here, so I guess it works. Of course, the foundation repair professionals might be like the old-time auto mechanics. Who ever questions their work?

Very closely spaced injection ports are installed, and then the surface of the crack caped. They then start injection into each port until it can be seen in the adjacent port. Very tricky installation on below grade foundation walls.