How to Do a Mosaic Front Porch

Clean the porch thoroughly with detergent and hot water. Use a push broom with stiff bristles to scrub the porch, then rinse it with warm water. Allow the porch to dry.

Fill any holes in a wooden porch floor with wood putty. Smooth the wood putty with a putty knife and allow it to cure for 24 hours. Sand the surface smooth. Patch a concrete or brick porch with a small batch of quick drying concrete. Smooth the surface of the concrete with a putty knife or trowel before it dries and allow it to cure for the length of time suggested on the package.

Create your design. A random design requires less preparation and precision. A design that includes representations of a landscape, for instance, or a recreation of a photograph requires sketching the design on the porch floor and completing each section of the design individually.

Work in manageable sections. Apply thinset mortar designed for use on the porch's substrate. Latex modified mortar, usually with the word "flex" in the title, works best with a wooden porch. Regular thinset works best with concrete or stone porches.

Spread the mortar about 3/8 inch deep onto a section of porch with a notched trowel if your design is a random pattern. Arrange the tile on top of the mortar and press it into place. Use a toothbrush or a narrow piece of wood to remove excess mortar that pushes up between the tiles and a damp cloth to wipe mortar off the surface of the mosaic.

Work in sections until the mosaic is complete. Allow the mortar to cure for 24 hours before adding self-sealing grout. Use a grout float to apply grout to the mosaic, taking care to make sure the grout fills the spaces between the tiles. Wipe off excess grout before it dries and follow the manufacturer's directions for cure time. Curing time for grout varies from a few days to a few weeks depending on the manufacturer.