Stone Veneer Installation

[nate0918]

I will first admit that this is not related to stoves or fireplaces, but rather a window well installation. Iv'e found it virtually impossible to get help from the stone veneer manufacturer. This forum has some fantastic stone masonry work so I was hoping for some help! I am applying thin stone veneer panels to a CMU window well. I am primarily concerned with how to seal it to prevent mildew since it will be in a shaded area all year round. The sealers I've tried (that claim they don't change the look of the stone) on test pieces really change the color. The panel on the left has a solvent based impregnating sealer applied, one coat, that was not supposed to change the color. The panel on the right has nothing applied and is the color I'm looking for. Any recommendations would be great, I am looking for no change whatsoever to the color. If this is not possible, is it possible to install with no sealer at all and just keep the stone clean with some kind of mild detergent? Any help would be greatly appreciated!

 

[GrumpyDad]

You might want to try a water based solution like 511. Oil based will change the color to orange. PERIOD. Water based usually does not.
Im struggling myself to find something that gives natural floor stone an actual gloss look with a touch finish. I see restaurants and resorts the top coat those giant pieces of flagstone, and that's what I want. It does darken it though a good bit.

Regarding mold/mildew, I dont know if it will help much. Anything with a porous surface is a natural home to such things. The back side of my house has that issue in areas where the sun just never hits it. So twice a year I have to lightly pressure wash/scrub. If the house were tilted just another 5 deg south I likely wouldnt need to do anything.

 

[nate0918]

The Miracle Sealants 511 solvent based version is exactly what I used in the pic. I'll try the water based and see if that makes a difference. Regarding the time of year for installation, what are the cons of installing it now, in the winter? Here in Oregon, it will occasionally hit freezing temps but only briefly on the occasional early morning. It will mostly be wet and cool for the next three months or so. Since this is in a window well, I was going to do the install in a day and cover the well and put a heater inside for a week. Does the constant moisture effect how much efflorescence will show up?

 

[GrumpyDad]

The Miracle Sealants 511 solvent based version is exactly what I used in the pic. I'll try the water based and see if that makes a difference. Regarding the time of year for installation, what are the cons of installing it now, in the winter? Here in Oregon, it will occasionally hit freezing temps but only briefly on the occasional early morning. It will mostly be wet and cool for the next three months or so. Since this is in a window well, I was going to do the install in a day and cover the well and put a heater inside for a week. Does the constant moisture effect how much efflorescence will show up?

I would seal when the weather is optimal unless you are literally trying to sell your house and get it to close. Ive painted with enamel from Sherman Williams when night time temps went 8 degrees warmer than it said I should paint, with a high level of humidity and rain going on for days. That door stayed tacky for weeks, then it developed this nasty white chalky stuff on it. Luckily it did eventually firm up, long after it was supposed to - and I was able to take a wet towel and wipe down the door.

I usually try to avoid hitting max/mins on any product. I believe they will advertise certain things to remain competitive and are willing to risk an angry customer or a few here and there in order to 'get the sale' advertising features they probably shouldnt.

If you test, there is no harm testing indoors in optimal temps/humidity. Then you will know what the result SHOULD look like when you apply outdoors within the specs of the product (they all have different temp/humidity ratings). But if it is going to be constantly damp, as in water splattering against it - the application may not last as long as it would if it had a nice long time to soak in and dry. The only benefit you have of doing it now is that the sun wont bake off or cure the solvent too quickly, which can also be a problem with products that are negatively impacted by the sun. Paint for example, I love painting/staining and putting things outside in the sun to quickly cure. Most paints react like this. But a water based solvent, I would want it to sit soaking in for as long as possible.