Do they make a non-liquid concrete/mortar color additive?

Question

I've been trying to find a cement additive to change the color of some mortar, but only seem to be able to find it in liquid form at my local big-box hardware store.

I'm looking for a similar product that can be added to dry mortar mix. Does this even exist? Where can I find it?

Back-story: I put down a patio of pavers a few years ago and apparently didn't put down thick enough plastic sheeting underneath. I skimped because the area seemed too shady to promote much weed growth. Boy was I wrong. I have major weeds growing through the cracks between the pavers.

My plan is to power wash the patio to get most of the sand out between the pavers, and then replace it by sweeping dry mortar over the patio and then misting it so it will harden and form a barrier for the weeds between the pavers. To get the color right I'd need to mix the color into the dry mortar before spreading it. I'm not sure how well this will work, but I am going to try on a small area first to see how it goes. If anyone sees any major pitfalls with this plan, please speak up in the comments.

Answer 1

I have worked with dry color for concrete. We poured a few slabs and some curb.

The dry power was available at a concrete supply house. It was expensive, but could be bought in small bags if needed. A little went a long way.

The color powder made a huge mess and stained everything. It was the consistency of powdered sugar. You need to mix it really well with the dry mortar or you will end up with varying color. You need to test the color by mixing up and curing a sample as it is hard to know exactly what the color will look like until it cures.

In this case, I would skip the color and use polymetric sand. Something like this: http://alliancegator.com/2011/?p=21

Answer 2

What you're looking for is called an integral color and is typically done with pigments.

Here is a source that I've used for other projects: http://www.directcolors.com/concretepigment/

Answer 3

I've seen powder concrete colorant on home improvement shows but to be honest I've never used it. The shows I've seen have had great results with it. Looks like you just throw it over wet concrete and let it soak in.

Answer 4

Sakrete sells a concrete coloring in powder form which is available at retail home improvement stores like Home Depot and Lowe's, and probably Ace Hardware as well. It comes in one pound boxes, and costs about $6-$7 a box, and they suggest a one pound box per 80 pound bag of Sakrete. That of course would be up to you and the desired color you're looking for. However, that gets pretty expensive if you have a large project that requires 20-30-50 bags and you can't use a redi-mix company due to access concerns!

I know there are a couple of other companies that sell bulk bags (100lb) and are available generally at concrete companies (like Redi-Mix). The biggest concern is matching the entire project: you're going to need to weigh it out or measure it somehow to maintain consistency. A little bit off doesn't really matter because the weather will eventually match it; however, if you're 15 shades off, weather isn't going to correct it.

I've seen many homeowners use it for landscape curbing and it worked out very well. It's very important that you mix it very well with the concrete prior to adding water to the mix or you'll have less than perfect results, guaranteed!

Answer 5

Don't know how helpful this will be, but colouring concrete used to be called "oxide" or "oxide powder" when I was growing up. Came in a plastic bag and was mixed into the cement powder with the sand. I recall my father using it.

You might need to find a builder's supply yard to get it.