Job at the old county courthouse changed how I do steps

Back in 2018 I had to match a set of steps at the old county courthouse in Richmond. They poured them in the 1920s and the mix was nothing like what we use now. Ever had to match an old mix where the aggregate was all different?

3 comments

3 Comments

drew_park1mo ago

Have you ever tried using white vinegar instead of acid? I read somewhere it's safer and still shows the real colors pretty well.

troyreed1mo ago

Washing the old aggregate with muriatic acid usually reveals the original color.

the_ryan1mo ago

Actually, @troyreed is mostly right about muriatic acid bringing out the original color, but you want to be careful with it since it can etch the surface too much if left on too long. White vinegar is definitely safer for cleaning, like drew_park mentioned, but it won't pull the color out the same way on really old set concrete. I'd stick with a diluted acid wash and just keep the contact time short to avoid damaging the aggregate.