Even the best-made fence will eventually need repairs. The effects of traffic, weather, and time all take their toll. A few simple fixes, however, can add years to the life of a fence. The commonest problem is rotten wood. Often, most of the board is still sound with only the ends decayed. A quick solution is to support the damaged board with a small block of wood (opposite). A board with more extensive deterioration can be supported by a sister rail (page 180). To ensure your repairs are long-lived, buy pressure-treated wood.
A loose post set in soil can often be stabilized by pressing down around the post with a tamping bar. If the post needs added support, bolt on 2-by-4 sister posts (page 180). For a badly damaged post set in soil or concrete, remove and replace the post (page 181).
Bricks occasionally need replacement when mortar joints crack or bricks are damaged. A loose brick can usually be worked out of the wall with a pry bar or the end of a cold chisel. A damaged brick may be removed with a cold chisel and a maul. First break the mortar around the brick, then split it into pieces small enough to free with a pry bar.
While stones have an indefinite lifespan, stone walls need frequent repair. As the stones settle under their own weight and endure stresses such as frost heaves, sections may collapse. Rebuilding a wall is not complicated but does require patience and lots of trial and error. Remove the stones down to the level where the wall is solid; often this means going right down to the ground. When rebuilding the wall, overlap the stones.
Wear goggles when drilling, work gloves and goggles to chip out mortar, and gloves when working with wet mortar. Wear gloves when handling pressure-treated wood, which contains arsenic compounds as preservatives; add a dust mask when cutting it.
Bracing the end of a rail
Cut a block the same width as the rail from a 2-by-4. Drill a pair of ⅛-inch clearance holes through the block so the screws can pass freely through it. Hold the piece of wood in place under the rail and screw it to the post with two 3-inch No. 8 galvanized wood screws (above).
Bracing the length of a rail with a sister rail
Cut off the damaged part of the rail. Cut a length of pressure-treated lumber the same size as the rail—commonly 2-by-4—to fit between the two posts. Position this sister rail underneath the old rail (or above if there is no room below) and clamp it every 12 inches. Toenail the sister to the post on both sides and underneath with 3½-inch galvanized common nails. Bore a ⅜-inch hole through both boards every 18 inches, offsetting them as shown (right). Install ⅜-inch carriage bolts in the holes, then remove the clamps. Fill in the gap in the rail with wood; fasten it with 3-inch galvanized nails.
Steadying a post with sister posts
Cut two pressure-treated 2-by-4s to a length at least half the height of the post to serve as sister posts; saw a 45-degree bevel at one end of each board. Position a sister post, bevel out, against the fence post. Place a scrap 2-by-4 against the top of the sister post and drive the post halfway into the ground with a maul (left). With a circular saw, cut off the top at a 45-degree angle 18 to 24 inches from the ground. In the same way, position and cut the other sister post on the opposite side. Bore two holes through the three posts and secure the sister posts with ⅜-inch carriage bolts. Trim the bolts with a hacksaw (inset) and file off any sharp burrs.
Positioning a replacement post
To indicate the location of the old post before removing it, run a string tautly between the posts on either side of the damaged post. Tie a marker string to the line on each side of the post (left). For a corner post, extend a line from both lengths of fence, past the corner post and secure each one to a stake (inset).
Removing the old post
Remove the rails and fencing on both sides of the post. Loosen the post and footing, if any, by removing the earth around the post with a shovel and a posthole digger, then rock the post back and forth. Install the replacement post as you would a new one, then reinstall the rails and fencing. If the post is too heavy to be lifted out by one or two people—especially if it is set in concrete—enlist the help of a car jack. Nail a 12-inch 2-by-4 to the post and nail a 2-by-6 under it, resting one end on the car jack and the other on a pair of concrete blocks (right). Support the car jack, and with a helper guiding the post, raise it with the jack.
Bracing with wood
Prop a block under the latch side of the gate to hold it in its correct closed position. Tack a brace the same dimensions as the rails diagonally across the top and bottom rails, and mark cut lines on its back along the rails (above). Cut the brace at the marks. Position the brace between the rails, bore clearance and pilot holes 1 inch from each end (inset), and drive 1½-inch No. 8 galvanized wood screws into the rail. Also drive a 1-inch screw into every other picket. If the gate still sags, try correcting it with a wire and tumbuckle stay (opposite).
Bracing with a wire-and-turnbuckle stay
Open a 3-inch turnbuckle to its full extension and attach a length of cable to each end with a wire clamp (inset). The cable length will vary with the size of the gate. Fasten a ½-inch screw eye to the corner of the top rail on the hinge side and the opposite corner of the bottom rail as shown, then attach the ends of the turnbuckle wires. Trim any excess wire with pliers. Tighten the turnbuckle to pull the gate back into square (above).
Placing a stone in a tight spot
You may be able to insert the stone by hand. If a little extra force is required, tap the stone in place with a maul, cushioning the blows with a wood block. Otherwise, enlarge the opening with the help of wood or metal wedges. With a maul, drive a wedge between the stone directly above the opening and the stones on either side of the opening. Drive in as many wedges as needed to enlarge the opening enough to reposition the missing stone. Insert the stone (above) and pull out the wedges.
Recreating a section of wall from the ground up
To rebuild part of a wall, remove a V-shaped section that extends as far down as necessary. Unless the stones are damaged in the second tier behind the first, leave those stones intact. Number the stones with chalk in the order you plan to remove them to make rebuilding easier (above, left). Working with a helper to lift the heavier units, start removing stones at least 2 feet to either side of the damaged area. A pry bar will help release any stubborn stones. To lower heavy stones, lay a 2-by-6 against the wall and slide them down it. If you go down as far as the ground, make a tamper by fastening a 1-inch-thick piece of plywood to a 2-by-4. Tamp the ground (above, right), adding gravel if necessary to make it level with the surrounding earth. Replace the stones, reversing the order in which they were removed. Seat each stone securely on the one below it, using small stones as shims if necessary. Work carefully to replace the top tier of stones; these capstones are twice as wide as the lower-tier units—and twice as heavy. Try tilting them into position, rather than placing them down flat. Fit small stones under them if necessary.