Producing a Smooth Finish Over Broom Finished Concrete

Hard troweled micro thin overlays can increase the amount of marbling
when stained

Question:
I have broom-finished concrete and want to acid stain it. All the acid-stained floors I have seen, and like, are smooth with hard-troweled finishes. Is there anything I can do to change my broom finish to a smooth finish so the stain will look better?

Answer:
The use of a microtopping, or thin overlay, is the solution. These ultra-thin polymer-modified cement-based overlays are easy to apply and most will take a stain. Make sure to check with the overlay manufacturer to ensure that their product is compatible with stain. Preparing a test sample prior to starting the project is always recommended.

Microtoppings can be applied with trowels, squeegees, or even hopper guns, depending on the type of finish desired. Smooth finishes are best achieved with a squeegee or trowel. Most microtoppings cure in 24 hours and can be stained any time after the initial 24-hour cure time. With microtoppings, you can use different finishing techniques to increase the amount of marbling and create more variegation when the stain is applied. These stained overlay surfaces will need to be sealed and maintained, just like a regular stained concrete surface. More information on thin-section overlays and staining can be found at concretenetwork.com or qcconprod.com.