In this short video, I’ll walk you through the grouting process step-by-step, using a mosaic rock as an example. The same techniques apply to all of my mosaic projects, so whether you’re finishing a mirror, heart, or garden piece, you’ll find plenty of tips to help you get a smooth, polished result you’ll be proud of.
For another perspective, this video is also excellent"
Watch on YouTube
How to Grout Your Mosaic — Step by Step
Grouting is the step that transforms your mosaic from a collection of glass pieces into a finished work of art. It can feel intimidating the first time, but follow these steps and you'll be fine. The video above walks through the full process — these written instructions are yours to keep.
What you'll need: Sanded grout, water, rubber gloves, dry rags or paper towels, and a piece of flannel or cotton fabric for the final buff.
Step 1 — Mix your grout
Add water to grout slowly and carefully, stirring thoroughly. The goal is a texture similar to peanut butter or brownie batter. It should NOT drop off a stick or spoon when held up — if it does, it's either too wet or too dry. Let the wet grout sit for 5 minutes, then restir and check consistency. Adjust as needed.
Step 2 — Apply
Put grout on your glass and press it into the cracks in every direction. After the surface is fully covered, remove what you can with your gloved hand. Be careful — glass edges can be sharp.
Step 3 — First wipe (5 minutes)
Wait 5 minutes and wipe the surface with a dry rag. You should be able to see the glass and beads, but some haze is fine at this stage. If grout is streaking across the glass surface rather than wiping clean, you may be pulling grout out from between the pieces — the opposite of what you want. Let it sit another minute or two and try again with a lighter touch.
Step 4 — Second wipe (5 more minutes)
Wait another 5 minutes and wipe again with a dry rag. All glass and beads should now be fully exposed and visible. You can remove any tape at this point.
Step 5 — Final buff (1–2 hours later)
Wait an hour or two, then buff the surface with a piece of flannel or cotton fabric. This removes the last of the grout haze and polishes the glass. Your piece should now be gleaming.
Step 6 — Cure time
Grout is fully cured in about 24 hours. Avoid getting it wet before then.
Have questions about grouting? I cover this in every class — find upcoming mosaic classes at hendersonartsllc.com/upcomingclasses.