Delaminated Concrete Floors can be a Concern for Replacement, Can it be Fixed?

By Category: Floor Restoration
When delamination occurs on concrete floors it causes many issues for building owners.

Delaminated concrete can occur with new or old concrete.

  • What has happened to the concrete here? This is newly poured concrete – what are the possibilities that caused this problem?
  • How do we repair the concrete without ripping it completely out?
  • What is the most cost-effective while giving the proper strength required?
  • Who is capable of performing these repairs?

How to Repair Delaminated Concrete Floors:

From looking at this pictures it may be hard to tell what has happened to this floor. The top layer is peeling off of the concrete – you can almost remove it with your fingers or by sliding something under it like a putty knife. The concrete beneath this sheared off top layer (the delaminated portion) is soft and chalky. What caused this newly poured concrete to delaminate or shear off and why is it only happening in some locations and not the entire slab?

There can be many causes, and we may never know exactly what happened, but somehow the mix design is contaminated, wasted for too long in the truck, or was improperly mixed (that would be the cause if the entire slab presented this problem). However, sometimes over watering will cause this issue in an isolated area as seen in picture 1. You can easily tell if the concrete presents this issue widespread or isolated by doing a chain drag (link to Wikipedia or something on chain dragging). This will allow you to listen for hollow spots. Hit those hollow spots with a hammer and sure enough, you will find a similar problem; the concrete will shear off and you will be left with not only an unsightly floor but a floor that can put you the contractor who poured it in a serious bind.

Remedies for this type of concrete repair will depend on the amount of area you have. For example, this location only had a 1,000 square foot section that was affected could be repaired with a simple overlay or skim coat of durable, featheredge concrete product. The first step is to remove all the bad concrete prep it for a new concrete application.

Repairing delaminated concrete flooring can be acheived with simple repair methods.

Properly keyed in edges will provide a strong hold at the edge.

 

The first step in repairing concrete that has delaminated is removing the bad areas.

This was a 1,500 SF area of delamination. Marked by chain dragging to locate the hollow spots.

 

 

 

 

 

 

 

This project was done in 2 phases and separated with a ¼” tall zinc transition strip. Once cleaned and prepped for application the new concrete can be installed.

Repairing concrete with patching compounds to resolve concrete delamination.

Installation on Side A with a high strength concrete repair patch.

 

Curing of the concrete will take 24 hours and griding can begin.

Side B is completed and is left to cure.

 

 

 

 

 

 

After a 24 hour cure this topping can be smoothed with a grinder to match the trowel finish of the adjacent concrete.

Finishing a concrete repair by grinding off the excess.

The finished result matches the exisiting slab. It can be topped with any regular floor topping, polished, or painted.