Historic Concrete Color: Here's the Formula!!

    When it comes to replacing our cracked and missing sidewalks or driveways, our Historic Preservation (HP) Guidelines state:  "Private sidewalks and driveways [as well as public] must be constructed of brush-finished concrete in medium grey tones, except where historical precedent demonstrates previous existence of brick, stone or other materials, which may be considered appropriate for replacement.  New concrete sidewalks and driveways should match the color of historic pavement in order to maintain the continuity of materials and character present in the district."

    In other words:  Stark white sidewalks and driveways are NOT allowed!  (Even though you'll see plenty of non-compliant sidewalks out there.)

    But here's the problem with the Guidelines:   the sidewalks in Mesta Park are not "medium grey."  Our sidewalks are more brown than grey, so if we're to "match the color of historic pavement", as the HP Guidelines require, then we have to figure out what color formula to use to get as close a match as possible.  This can be challenging, to say the least, and I've observed inconsistency with the resulting color.

    The best result I've personally seen is located at 916 NW 18th St., where Lori Wrotenbery recently replaced her sidewalk, driveway, and a portion of her retaining wall, while keeping a section of the historic retaining wall.  Lori's father, who worked as her contractor, passed along the following information about the color formula he came up with:

• "The color system we used for the recent concrete job at 916 NW 18th St. was 'Scofield Integral Color SG', which is used by Swartz Redimix.  From the Color Chart A-322.02, we used 'SG677-2 Ripe Chestnut'.  It comes in 10 lb. bags at about $30-$35 per bag, and it is added at the mixer at the formula quantity which was, as I recall, about 5 to 6 lbs./yard.  This adds about $20 per yard to the costs.  If I had it to do over again, I might have had them add 1 or 2 lbs. extra to the formula to darken it slightly, but we are pleased with the result." 

    This is invaluable information, and if you want to check out the results for yourself, go by 916 NW 18th St.  Yes, it adds to the cost of the job;  however, to be in compliance with the HP Guidelines, we are required to match the historic color as best we can.  This formula takes some of the guesswork out of the mix. 

    Thanks to Paul Wrotenbery for taking the time to pass on this information.  Let me hear from you with questions!