Durable Grout for Flagstone Set in Crushed Stone

To learn more about PerkGrout check out this video.

Why PerkGrout™?

  • Eliminates messy fines and washouts
  • Crack-resistant and long lasting
  • Reduces weeds, critters and other maintenance
  • Permeable


PerkGrout™ is a polymer modified pervious concrete using a non-shrink cement to produce a durable, crack-resistant grout for flagstone set in compacted base rock (crushed stone) or pervious concrete.


PerkGrout™ is supplied in 30 lb sacks in either ‘Grey’ or ‘Tan’ color. Exactly one full quart of water is mixed with each sack, either in a mortar type mixer, in a bucket with a drill mixer, or in a tub by hand.

Custom colors for large orders are possible and one can add their own powder concrete color pigment.

How to install PerkGrout video.

How to install PerkGrout pictorial.

Each 30 lb sack covers approximately 17 square feet of flagstone area. This assumes mostly larger, 18” size flagstone pieces, 1” to 2” wide joints and 2”depth.


Handy homeowners and landscape professionals can install PerkGrout™.


Each 30lb sack of PerkGrout costs $19.95 in retail locations and $33.95 when purchased online and delivered to you.  So installed, it is typically from $1 to $2/square foot.  When purchasing online from our store we only charge $14 per bag for shipping (USPS flat rate is over $16), and there are no handling fees.  For larger orders, please contact us directly.  Please allow about 1 week for delivery, though sometimes this can take longer these days (see note on orders page).


See more pictures of PerkGrout.