How to Cast a fountain from Concrete

Use basic materials and clever techniques to create a water feature in one weekend.

About This Project

• Overview and Preparation
• Step-by-Step Pictures and Instructions: How to Cast a Fountain
• See More Exterior Projects

If you want to add the sight and sound of moving water to your yard without the heavy work and frequent maintenance of a pond or waterfall, consider a fountain. Unlike a pond or waterfall, a freestanding fountain doesn't require hard labor and there's very little maintenance to do later. Best of all, you can place a fountain just about anywhere: among plants, inside a sun porch, or on a deck or patio. You could even build a pair to flank a gateway or path. This article will show you how to cast a fountain using inexpensive off-the-shelf materials. Our design combines the style of top-selling models found at garden centers with super-simple construction techniques. If you can handle basic tools like a circular saw and drill, you can build it, even if you've never worked with concrete before. Expect to spend about six hours assembling forms and pouring concrete, plus another couple of hours removing forms and setting up the fountain. The materials for this fountain cost about $120. Fountains of a similar size and style (usually made from fiberglass or plastic) cost about $500 at garden centers.

Combine basic materials and clever techniques to create a fountain in one weekend.
Build forms from foam
To mold concrete, you pour wet concrete mix into a form. You can build forms from wood, but we found that rigid foam insulation is perfect for a small project like this. Foam is lightweight, smooth and easier to cut. Concrete won't stick to foam, so you can reuse the outer form parts to cast several fountains. Best of all, you can assemble sections of foam with the ultimate quick-and-simple fastening system: duct tape! Be sure to use "extruded" polystyrene, not "expanded" polystyrene bead board. A 4 x 8-ft. sheet of 2-in.-thick foam costs about $20 at home centers. Inspect the sheet before you buy, and handle it carefully - deep scratches or dents will show up as bumps on the surface of your fountain.

Figures B and C show the dimensions of the column and basin form parts. Cut the tapered parts (A and C) with a circular saw using a standard wood-cutting saw blade (Photo 1). It's difficult to make perfectly straight cuts with a circular saw because the blade can easily wander in the soft foam. But don't worry about slightly wavy cuts; they won't affect the final product. Cut the square and rectangular parts with a table saw or circular saw. Cut the 8-in. round disc (D) with a drywall saw. Wrap the disc with duct tape to cover the rough edges left by the drywall saw.

FIGURE A: Cast concrete fountain

Materials List
• One 4 x 8-ft. sheet of 2-in. extruded polystyrene foam insulation
• Four* 80-lb. bags of concrete mix (or five 60-lb. bags)
• Four* 10-oz. bottles of Quikrete Cement Color or equivalent
• 2 ft. of 1/2-in. PVC pipe
• 2 ft. of pump tubing
• 2 ft. of 10-gauge insulated copper wire

Duct tape, 3-in. screws, 20-minute setting-type joint compound (1 bag),
12-in. flowerpot, 3-in. ABS toilet flange, hot glue, 9- or 10-in.-diameter ball,
1/2-in. galvanized hardware cloth, river pebbles.

Pump: Select a pump that delivers at least 300 gallons per hour and includes adjustable flow control. Pumps are available at home and garden centers. To find online sources for the pump we used, type "Beckett M350AUL" into any online search engine.

*Three 80-lb. bags of concrete filled our forms, but just barely. Since the amount of concrete in a bag can vary slightly, we recommend you buy four bags and four bottles of colorant.

Assemble the forms with duct tape
To begin, cut out the foam parts and assemble them. Keep in mind that you'll build the column and base forms and pour them in the upside-down position. Also, be sure to place the printed side of the foam face out; the ink can stain the concrete.

Tape the seams of the outer column form together and then wrap it with tape. Stretch the tape firmly as you wrap to create tight seams.

Assemble the inner form with tape and 3-in. screws (Photo 2). Tape the basin form sides (G) to the base (H). Screw one basin block (F) to the base, then screw the second block onto the first. Mark a 4 x 4-in. square on the block to represent the opening at the bottom of the column. Then cut two slits in the foam and insert anchors made from 10-gauge copper electrical wire (Photo 3). Leave the legs of each anchor protruding 3/4 in. from the foam. You'll use these anchors later to tie the column and basin together (see Photo 8). Be sure to use plastic-coated wire. Copper that's in direct contact with concrete eventually corrodes.

Fill the forms with concrete
Since the concrete isn't reinforced with wire mesh or rebar, concrete mix that contains tiny threads of fiberglass is best for this project (Quikrete Crack-Resistant concrete is one brand). We used one 10-oz. bottle of Quikrete Cement Color per 80-lb. bag of concrete to pigment the mix.Home centers typically carry three or four colors (we used "buff"). For mixing tips, go to familyhandyman.com and type "mixing concrete" into the keyword box.

Fill the sphere form first, before the mix begins to stiffen. Shake the form to drive out large air pockets. Then insert a 24-in.-long piece of 1/2-in. PVC pipe (see Figure A and Photo 7). Cover the end of the pipe with tape to keep out the concrete. Center the pipe and hold a level against it to make sure it's standing straight up.

Fill the column form by dropping in scoops of concrete on all four sides. If you fill only from one side, you'll bend the inner form. When you've dropped in about 6 in. of concrete, tamp it with a 1x2 to fill in large voids. We tamped for about 10 seconds; more tamping will give the concrete a smoother surface, while less tamping will leave more craters and crevices. Whatever surface texture you want, be consistent with your tamping all the way up for a uniform appearance. Continue to fill and tamp in 6-in. increments until the concrete is 4 in. from the top of the form. Then add the block that creates the access hole and the wire anchors (Photo 5).

When you fill the basin form (Photo 6), tamp the concrete the same way and be careful not to dislodge the wire anchors you installed earlier. Slide a 2x4 back and forth as you drag it across the form to screed off the excess concrete.

Wait, then remove the forms
Let the concrete "wet cure" for at least a week before you remove the forms. The longer concrete stays damp, the stronger it gets. Cover the column and basin with plastic garbage bags to slow down evaporation. To remove the sphere form, just break it away (Photo 7). To remove the outer forms of the column and basin, simply slice the tape with a utility knife. To remove the blocks (F) inside the basin, cut the foam into sections with a drywall saw and break them out. Removing the column's inner form is a slower process; cut the foam with a drywall saw and pry out small chunks with a putty knife, and then cut some more.

Put it all together
Before you assemble the fountain, mount a 3-in. black plastic toilet flange in the recess at the top of the column (see Figure A and Photo 8). The flange supports the sphere and stands about 1/4 in. above the top of the column. This allows water to fill the recess and spill out over the sides of the column. Cover the screw holes and bolt slots in the flange with duct tape, then set it in place. Apply lots of hot glue over the flange and around it to lock the flange in place and plug all the holes watertight (the tape prevents the glue from dripping through holes).

The column and basin weigh about 100 lbs. each, so you'll need a helper or a mover's dolly to move them. Tie the anchors together with the same wire you used for the anchors (Photo 8). Then nudge the column to make sure you twisted the wires tightly enough. It's OK if the column rocks slightly, but it must be absolutely tip-proof since the fountain will attract curious kids.

Connect a 2-ft. section of flexible tubing to the sphere's PVC pipe. The vinyl tubing made to fit our pump slipped tightly inside the PVC pipe. If your tubing doesn't fit tightly, use hose clamps or other fittings. Set the ball in place (Photo 8, lower) and position the pump. Trim the tubing to length and connect it to the pump. We filled the recess at the top of the column with smooth black "river pebbles." In the basin, support the pebbles with four "cribs" from 1/2-in. wire mesh (called "hardware cloth"). Cut the mesh into 9-1/2-in. x 12-in. sections, then bend them over a 2x4 block to form cribs 3 in. tall, 3-1/2 in. wide and 12 in. long. Cover the cribs with pebbles. This leaves all the space below the cribs open for water storage. If you simply fill the basin with pebbles, you'll greatly reduce the water-holding capacity.

Fill the basin with water and start the pump (the outlet that powers the pump must be GFCI protected). Turn the flow-control knob on the pump to adjust the water flow. If the water spills down one side of the column but not the others, slip a flat pry bar under that side of the basin. Raise the basin and place shims under it until water flows evenly down all four sides of the column.

The fountain loses water because of splashing and evaporation, so keep an eye on the water level whenever you run the pump. If the basin runs dry, the pump will burn out. On a very hot, windy day, you may need to add water after just a few hours. In a cold climate, freezing water could crack the basin and destroy the pump. Each winter, remove the pump, empty the basin and either move the fountain indoors or cover it with a plastic bag.