Specifications for polished concrete slab
EvanLeBrun
| Posted in General Discussion on
We’re about to pour a slab for our new home. We’d like polished concrete for our finished floor, but I’m having a hard time finding what specifications to give our concrete contractor to ensure our slab is suitable for polishing. What mix or finishing techniques should I ask for?
Replies
Check out this link. https://www.concretedecor.net/departments/grinding-polishing/design-and-performance/
It is an article explaining some of the issues to be aware of.
Also as bullet points:
Do not add air to the concrete if at all possible. If you feel the need to have air-entrained concrete, try not to exceed 3%.
Use a minimum 3,500 PSI mix. Between 3,500 and 5,000 is preferred for polished concrete. 3,000 PSI is normal for concrete driveways, concrete sidewalks and patios.
Fly ash should not exceed 20 percent of the total cement.
It’s best not to use calcium chloride accelerators. NCA is a great replacement product that will accelerate the drying process.
If exposing the aggregate is planned, it’s very important to understand how the aggregate is going to look once it becomes polished.
If adding rocks, large flat rocks are an excellent choice.
Color hardeners that sit on top of the concrete can potentially be ground off, so use a color that’s designed to go in the concrete truck.
The slab should be power troweled flat, but preferably not burned in.
Thank you! This is super helpful.