Concrete birdbaths get brittle with age, and a misguided weed trimmer, a bump from a lawn mower or a ball that goes out of bounds can cause a chip. You're certainly helping the birds when you provide them with a birdbath full of clean water. When they can bathe in clean water, their feathers are better able to insulate them from extreme temperatures. Birds that bathe also have fewer parasites. Instead of buying a new birdbath, repair the chip in yours. Properly repairing and sealing the chip means you'll be able to use your birdbath for many more years.
Drain the water out of the birdbath. Wipe any remaining moisture out of the birdbath with a towel. Allow the birdbath to dry in the sun for a day.
Put on work gloves. Brush the chipped area with a wire brush to remove any crumbling or loose pieces of concrete. Wipe away any dust particles with a towel.
Dip a paintbrush in concrete bonding adhesive. Apply a thin coat to the chipped area in the birdbath. Concrete bonding adhesive enables concrete patch to adhere to the surface without future chipping. Bonding adhesive usually has a milky color and turns clear when it dries.
Scoop a small amount of fast-drying concrete patch onto a trowel. Fill the chipped area with the patch so it's level with the surrounding area. If the chip is on a rounded area, use a craft stick to round the patch in the chip and match the original shape.
Allow the concrete patch to dry for 30 minutes, or according to the package directions.
Place a thick layer of newspapers on a solid, flat surface, such as a patio or driveway.
Shake a can of masonry sealer up and down for 5 minutes to mix the contents thoroughly. Pry the lid off with a flat screwdriver.
Dip a paintbrush into the masonry sealer and apply a thin layer evenly to all surfaces of the concrete birdbath. Start from the bottom of the birdbath and work in even strokes to the top. Allow the sealer to dry completely for one to two hours before placing the birdbath in its place and filling it with water.