How to clean stained new concrete?

Submitted by Maletor t3_11boz5e in DIY

What is the best option to clean this concrete?

It's brand new and the home builders kept plywood on it that stained it. Their proposal was to acid wash it and some quick research showed this was probably a bad option, but wanted a second opinion.

It's been pressure washed thoroughly and there was no luck.

Sand blasting is the only other option? Is that dangerous with the house close by?

https://imgur.com/a/En7A6Kj

8

Comments

You must log in or register to comment.

Wide_String2861 t1_j9z0o9e wrote

A muriatic acid based cleaner is what you’re looking for I believe. Make sure you read about safe use because, obviously, it’s an acid and a pretty strong one at that.

Should be available at your local hardware store as well.

Good luck!

4

Captainthistleton t1_j9zehfm wrote

Find a contractor supply company or Ready Mix concrete producer they have a lot of products for cleaning concrete.

If it's oil type of stains Mineral Spirits works well if it's other type of grim get a professional product and follow the directions to a T.

1

ricardostpierre t1_j9zriuv wrote

I got a week-old motor oil stain out of new concrete with some oxyclean and some water—may wanna try that if you already have some on hand.

2

CorvisTaxidea t1_j9zwur6 wrote

Google plywood stains on concrete and you'll get a lot of hits. I found this in the first one: "Extracts from wood may cause yellow or brown stains in concrete. The stains can be removed by treating the concrete with a hypochlorite solution. Household bleach, which is usually about 5 percent sodium hypochlorite, is satisfactory after diluting one part of bleach with four to six parts of water. The stain disappears if the surface is first scrubbed thoroughly with a solution that is one part glycerol in four parts water. Glycerol is flammable and bleach is corrosive to skin. As always, read the warning labels on the chemicals before use."

1

imnotsoho t1_ja08x21 wrote

I thought you were talking about "stained concrete" not concrete with stains. I stained my own floors with an acid stain.

1

lokicramer t1_ja0vzjn wrote

It will naturally be gone in 6 months

1