How to Seal Concrete Crafts (Indoor and Outdoor Sealers)

Before any sealer touches your concrete, make sure the piece is fully cured. Fresh concrete looks dry on the surface long before it has hardened all the way through, so give it at least 24 to 48 hours, and longer for thicker pieces. Seal too early and you trap moisture inside, so the coat will not bond.

Once it is cured, wipe it down. Run a dry cloth or a soft brush over the surface to clear off dust and loose grit. Any powder left behind gets locked under the sealer and shows up as a rough patch, so a quick clean now pays off later.

This is the decision that matters most. For indoor pieces, a water-based acrylic sealer is the friendly pick: low odor, quick drying, and it wipes on clean. If the piece will hold a candle, food, or water, step up to a food-safe sealer rated for that use. Bree uses a non-toxic, water-based sealer on her candle jars for exactly that reason.

For anything living outdoors, reach for a penetrating outdoor sealer. It sinks into the concrete instead of sitting on top, so it handles sun, rain, and freeze-thaw without peeling. Match the sealer to the job and the finish holds up.

A foam brush is the tool for this. It lays sealer down smooth with no bristle marks, and it costs little enough to toss when you are done. Dip it into the sealer and coat both flat sides evenly.

A little goes a long way, so press the brush against the rim of the jar to squeeze off the extra. You want the foam damp, not dripping. Too much sealer at once pools in corners and dries cloudy, so build it up in thin passes instead.

Start your first coat in straight vertical strokes and work your way around the whole piece. On the inside of a vessel, run the brush from the base up to the rim, turning the piece as you go so you cover every section.

Here is the handy part: the sealer darkens the concrete a little where it lands. That wet line shows you exactly what you have covered and what you still need to reach, so you are far less likely to miss a spot. Keep the coat thin and even.

Let the first coat dry. Bree finds hers is ready in about half an hour to an hour, though a thick coat or a humid day takes longer. When it no longer looks or feels tacky, go back in with a second coat.

Run this one in horizontal strokes, crossing the direction you used the first time. That cross-hatch catches any thin spots and evens out the coverage. Two coats is the standard for most pieces. Add a third if you want extra protection on something that will get heavy use.

The bottom is the part people forget, and it is the part that sits on your furniture. Load a little sealer on the corner of the brush and swirl it across the base until the whole underside is coated. Get the bottom edge where the wall meets the base while you are there.

Sealing here does two jobs. It stops raw concrete from scratching or leaving gray marks on a table, and it blocks moisture from wicking up through the base. A sealed bottom is what makes a piece safe to set down anywhere.

Give the sealed piece a full 24 hours to cure before you use it or add anything to it. Bree waits at least that long before pouring wax into her jars, and the same patience pays off for a planter or a dish. Rushing it now undoes the work you just did.

Once it is cured you can leave the finish as is, or buff on a thin coat of clear wax for a soft sheen and a little extra water resistance. To keep a sealed piece looking good, wipe it with a damp cloth and skip harsh scrubbers, which wear the sealer down over time.