QUESTION

Why am I getting More Efflorescence after Sealing my Saltillo Tile? Hope you can help. I have a failed stone sealing job and I need an expert opinion to help me decide what to do next.

A contractor recently stripped and re-sealled 1600 sq ft of saltillo-type pavers at my home in Fullerton, CA. I've had excessive efflorescence ever since. I had some efflorescence before, but nothing like this.

One thing I think I'm observing is efflorescence getting impeded by the sealer before pushing through. Many tiles get characteristic dark splotches that eventually become below-the-surface efflorescence that doesn't come off with a scrubbrush. In many but not all cases these tiles then get standing efflorescence that cakes up where the splotches are below.

I'm wondering if the problem started because the sealer was put down before the tiles could dry out completely from their heavy pressure-washer cleaning and the subsequent rains we got.

We used a water-based acrylic sealer

I'm interested in having you come out and do an investigation.
Why am I getting More Efflorescence after Sealing my Saltillo Tile? Hope you can help. I have a failed stone sealing job and I need an expert opinion to help me decide what to do next.

A contractor recently stripped and re-sealled 1600 sq ft of saltillo-type pavers at my home in Fullerton, CA. I've had excessive efflorescence ever since. I had some efflorescence before, but nothing like this.

One thing I think I'm observing is efflorescence getting impeded by the sealer before pushing through. Many tiles get characteristic dark splotches that eventually become below-the-surface efflorescence that doesn't come off with a scrubbrush. In many but not all cases these tiles then get standing efflorescence that cakes up where the splotches are below.

I'm wondering if the problem started because the sealer was put down before the tiles could dry out completely from their heavy pressure-washer cleaning and the subsequent rains we got.

We used a water-based acrylic sealer

I'm interested in having you come out and do an investigation.

ANSWER

ANSWER - Looking at the data sheet for the Acrylic Concrete Sealer it isn't clear whether it is a breathable sealer or not.

Non-breathable sealers can trap moisture within the tile that normally produces a cloudy discolored look.

The Saltillo tiles are suppose to be dry before applying the sealer.  Although the source of the moisture, and the resultant efflorescence, could be coming from the concrete substrate below the tile.

If you don't have a vapor retarder under you concrete slab or it doesn't continue up the sides of your slab and footings, and if water can migrate towards the slab for a number of different reasons, then that could be the source of the moisture that carries the salts/efflorescence to the tile surface.

So the efflorescence is a symptom of a moisture problem.

We do have a lot of experience and expertise in evaluating tile and sealer issues.  We can perform a visual and intrusive inspection of the tile assembly and perform laboratory testing to determine the source of the efflorescence and the nature of the sealer, and provide recommendations on how to remediate the problem.

 
ANSWER - Looking at the data sheet for the Acrylic Concrete Sealer it isn't clear whether it is a breathable sealer or not.

Non-breathable sealers can trap moisture within the tile that normally produces a cloudy discolored look.

The Saltillo tiles are suppose to be dry before applying the sealer.  Although the source of the moisture, and the resultant efflorescence, could be coming from the concrete substrate below the tile.

If you don't have a vapor retarder under you concrete slab or it doesn't continue up the sides of your slab and footings, and if water can migrate towards the slab for a number of different reasons, then that could be the source of the moisture that carries the salts/efflorescence to the tile surface.

So the efflorescence is a symptom of a moisture problem.

We do have a lot of experience and expertise in evaluating tile and sealer issues.  We can perform a visual and intrusive inspection of the tile assembly and perform laboratory testing to determine the source of the efflorescence and the nature of the sealer, and provide recommendations on how to remediate the problem.