Flagstone Sealer

A flagstone sealer is no different than other types of concrete or stone sealers - you just happen to be applying it to your flagstone surface. Most people think that just because natural stone is hard, it's impossible to damage or stain. The fact of the matter is that stone and concrete surfaces are porous substances that can and will stain. To protect it and bring-out the natural beauty of the product, you'll need to apply a sealer to it.

A good solvent-based sealer will do just fine in protecting your flagstone because it is:
  • UV stable and won't yellow.
  • It is breathable (if you use a non-breathable sealer, you might end-up getting blotchy areas on the stone.
  • It is easy to apply - a nine inch roller with a broom handle attached works just fine! Dip and roll right out of the bucket!
  • Very durable - a couple of coats and you may not have to think about re-sealing until three to five years (depending on the amount of traffic it gets).

The picture below is of a decorative flagstone overlay on a front porch - sealed with a solvent-based acrylic sealer:
Flagstone Sealer

Solvent-Based

Not all solvent-based sealers are created the same - if you're serious about getting a good brand, you have to do some research to find out how well the sealer performs over time. You might want to look at some other flagstone jobs that have been sealed for a while to compare and see how well the sealer is holding up.

Water-Based

Although not as durable, a water-based sealer does have it's uses. If you're conserned about changing the appearance of the flagstone with a solvent-based sealer (and believe me, it will go to several shades darker when using a solvent-based product), you could always use a water-based version.

Going this route, you'll have little or no change in color of the stone - this is especially nice if your wife really loves the color "as is" and then you go an screw it up by making them too dark!

With no VOC's and no worry about killing the plant life around your stone (especially if you have a large area to cover and you're using a pump-up type sprayer), you'll want to seriously want to consider the water-based flagstone sealer.