SCALING AND SURFACE DELAMINATIONS Evaluation and Repair

Another way to make concrete easier to finish

SCALING or BLISTERING The easiest way to fix scaling or blistering problems is to make sure they don’t happen!

SCALING  Depending on the cause, scaling typically happens fairly quickly, but can wait for months or until the first cold season to become visible;  Light scaling does not expose the coarse aggregate;  Heavy scaling exposes virtually all of the aggregates.

Fixing Scaling Problems  Light Scaling There is no cost-effective way to return the surface to its original condition, so unless there are safety concerns, do nothing to the surface; Apply a silane or alkoxy-silane sealer to the clean, dry surface until it is saturated, and no further liquid can be absorbed;  There is only one chance to apply a penetrating sealer since after the first application the surface has been sealed to prevent any further absorption.

Fixing Scaling Problems  Heavy or Significant Scaling: Remove top surface by blasting or grinding. If appropriate, do not re-cover the treated surface; If original surface texture is to be restored, apply a specialty self-leveling topping mixture to the effected area; Apply a silane or alkoxy-silane sealer to the clean, dry surface until it is saturated, and no further liquid can be absorbed;

BLISTERS – New blisters can continue to form under tiles and other surfaces for many months or even years after the concrete has been placed; – If covered by tile or linoleum, can become a significant maintenance problem; – Less visible or troublesome if covered by carpet.

Fixing Blisters  There is no inexpensive way to fix blisters. If only the visible blisters are treated, new blisters may form under the surface long after the treatment; If moisture is the cause, eliminate the source of the moisture, if possible; The only effective way to treat the blisters is to remove the entire affected area and, if exposed to the environment, treat with a silane sealer.