How to Build a Simple Sliding Gate

Design your gate, trading off the weight of the finished project with the strength you need to be inherent in the structure: If the purpose of the gate is to keep pets in a specific area or to exclude, for instance, goats from a flower garden, the gate need only be waist high and built with enough inherent strength to resist flexing when in use. If the purpose of installing the gate is to exclude trespassers, it should be at least as high as the fences it interrupts and built to withstand efforts to force it open or knock it down.

Home improvement warehouses often have free-of-charge project sheets that offer sizing recommendations and structural plans; gate-building instructionals are likely to be in the lumber aisle.

Make the gate from pressure-treated lumber; buy the “finished” grade, because “unfinished” wood risks splinters when you're using the gate. Cut the timbers that will form the frame of the gate and lay them out on a flat, level surface. Ensure that the frame is square, then insert a brace or several braces as determined by the gate’s size and purpose. Fix these timbers together using exterior-grade wood adhesive and decking screws. Attach the gate panel, be it solid wood, a series of planks or even chicken wire.

Fit rollers to the bottom of the gate and a latch to the top leading edge. Fit roller-bearing guides to the inside of the gate post that the gate will slide past, and fit the latch receiver on the inside of the gate post that the leading edge of the gate will slide toward as it is being closed. All these specialty components should be available from a home improvement warehouse or hardware store; if they are not, you can special-order them. All should be delivered with comprehensive installation instructions.

Use a shovel to dig out a shallow ditch on the inside of the fence, between the fence posts and extending -- on the side of the gateway that you want the gate to slide to when open -- to a distance that equals the length of the gate plus 1 foot. The ditch should be 1 foot wide and between 4 and 6 inches deep, depending on the weight of the gate. Fill the floor of the ditch with course gravel to a depth of 1 inch, and arrange a trellis of rebar along its whole length. The rebar should be supported approximately 1 inch above the gravel on stones.

Fill the ditch with concrete to a depth of 1 inch below ground level. Lay a length of 1-inch-by-2-inch perfectly straight wood on the wet concrete, resting on its wider face. The wood should extend past the ends of the ditch an inch or two; this will facilitate drainage of the track.

The wood must be absolutely parallel to the fence line and stepped inward from the gate posts the same distance that the roller-bearing guides protrude from their gate post. For instance, if the rollers beneath the gate will be 2 inches inside the gate posts because the offset of the roller-bearing guides is 2 inches, then the center of the wood must be 2 inches from the post side of the ditch.

Top off the ditch with concrete around both sides of the wood, being careful not to let the infill process shift the wood. Use fiber-reinforced premixed concrete for this stage; although more costly, its inherent strength will prevent chipping as the gate rollers move through the track. Trowel off the top, and remove the length of wood 2two-thirds of the way through the set time advised on the packaging. Allow the concrete to fully cure before proceeding.

Install the gate from the open end of the track, sliding it carefully through the roller-bearing guide. Dig out a post hole at the open end of the concrete-filled trench and install a post to keep the gate from sliding too far -- and jumping the track when it is opened.