How To Install Wainscoting

Panel molding: WOBB002 Greek Revival Band Mold. Primed lumber: WindsorONE and Protection Pre-Primed Trim Boards. All from Windsor Mill.

Overview for Installing Wainscoting

Day-to-day timeline

Friday: Prep the wall and determine the panel widths (Step 1-2). Saturday: Install the panels, rails, stiles, and baseboard (Steps 3-10 ). Sunday: Install the chair-rail parts, base moldings, and panel trim (Steps 11-17).

Step 1: Remove the Base Cap

Old baseboard makes a good nailer and can stay put as filler behind the new baseboard if you remove any cap molding. Score its seams with a utility knife and, starting at one end, work it loose with a pry bar.

Step 2: Lay Out the Walls

Decide your wainscot height, and run a level line of painter’s tape across the wall above it. Divide the width of the wall by the number of panels you’d like, and use that measurement to make hash marks on a strip of wood longer than the wall. You just made a swing stick—a tool that maintains even spacing as you adjust it diagonally to fit the panels onto a wall. You must account for the fact that each wall has one more stile than panel, so first pad out the wall’s lower corner with one stile plus the thickness of the adjacent wall’s wainscot. Butt the swing stick against this blocking, lower the other end until a hash mark lines up with the wall’s far edge, and tape it in place. Use a level to transfer the hash marks to the painter’s tape, as shown, which gives you the distance from the outside edge of one stile to the inside edge of the next.

Step 3: Install the Panels

Make a level line around the entire room, set at the height of your wainscoting minus the height of the chair-rail cap. Use a circular saw to cut ¼-inch plywood, grain oriented vertically, to fit between the old baseboard and the level line. It’s okay to have a little wiggle room. Rip the panels so that the seams will be covered by the stiles, keeping in mind that the hash marks locate the edge of a stile—not the center. Apply panel adhesive to the back of each piece with a caulk gun and press it in place.

Step 4: Install the Top Rail

Using a stud finder, mark the location of the studs on the painter’s tape. Cut the 18 top rail to the length of the wall using a circular saw. Have a helper hold the top rail up to the level line. Using a nail gun and working from one end to the other, nail through the rail and into the studs with 2½-inch finishing nails.

Step 5: Install the Stiles

To determine how long to cut your stiles, first measure the distance between the top rail and the old baseboard at three points. Use the shortest one and subtract the height of the bottom-rail stock. Set up a stop block on a miter saw and cut all the stiles to that length. Then cut a scrap spacer block to your panel width marked on the tape, minus the width of one stile, and use it to place the stiles uniformly. Apply panel adhesive to the back of each one and attach using a nail gun and 2½-inch finishing nails.

Step 6: Trim and Install the Corner Stiles

Where two stiles meet at the corners, the overlapped piece must be wider by the depth of the stock. Rip a wider stile from larger stock for each corner. Butt the wider stile against the adjacent wall and glue and nail it in place. Then butt the adjacent wall’s stile into the first, as shown, and glue and nail it in place.

Step 7: Cut Existing Trim

To slip stiles behind existing molding, like the horn of a window’s stool, use a flush-cutting saw to cut the horn where it meets the wall. Use the thickness of the stile to guide the saw, as shown, and cut toward the casing. Use a chisel to knock out the block and clean up the notch. Tip: If you don’t have a flush-cutting saw, also called a Japanese saw, mark the thickness of the stile on the horn and cut it with a handsaw.

Step 8: Install the Bottom Rail

Snug the bottom rail up against the ends of the stiles and wedge shims between it and the baseboard to tighten the joints. (The new baseboard will cover any gaps.) Nail through the rail and into the studs using 2½-inch finishing nails.

Step 9: Scribe and Rip the Baseboard

Nail scraps from the ¼-inch plywood to pad out the existing baseboard and bring its face flush with that of the bottom rail. Set the baseboard in place and shim the low end until the piece is level. Measure the biggest gap between the bottom of the baseboard and the floor, and cut a scrap block to this size plus ¼ inch. Run the block along the floor against the baseboard with a pencil on top to scribe a cut line on the piece, as shown. Rip the baseboard using a circular saw.

Step 10: Install the Baseboard

To make sure the rail and baseboard are parallel, cut a spacer to match the amount of bottom rail you want exposed, and use it to position the baseboard while nailing it in place, as shown. The shoe molding will cover any gap along the floor.

Step 11: Cut the Apron

Each run of molding will either turn a corner—in which case you’ll miter the end—or meet an opening. At an opening trimmed with a deep casing, the apron can simply die into the casing. Otherwise, you’ll have to create what’s called a return to dress the cut end: Miter the run at 45 degrees as if for an outside corner, and then miter a second piece that will meet that 45 and die square into the wall or casing—turning the profile around the corner (as shown in the inset photo). Just be sure to cut the return’s mitered end first; that task is made much easier when working with a long piece.

Step 12: Install the Apron

Align the top edge of the apron flush with top edge of the rail and nail it in place using 2½-inch finishing nails. On any run with a return, nail the run in place first and glue the return into its slot with adhesive caulk.

Step 13: Create the Returns

At the end of a run where the chair rail requires a return, again, miter the end as if for an outside corner, then miter and cut a return to terminate the molding profile into the wall or casing. For the cap, you’ll want to glue the return to the run to create an assembly, as shown.

Step 14: Notch the Return

Depending on your existing casing, the chair rail may need to be notched. If so, hold the chair rail in place, scribe the shape of the molding, and then use a handsaw to cut the notch. Notching the existing casing to accept the cap, as shown, will give you a nicer joint.

Step 15: Install the Chair-Rail Cap

Once your returns are assembled, miter any ends that finish at a corner. Set the cap in a bed of caulk and nail it to the ledge formed by the apron and upper rail using a nail gun and 2½-inch finishing nails.

Step 16: Install the Base-Cap and Shoe Moldings

Miter corner ends. Position the shoe molding on the floor against the baseboard and the base cap on the top edge of the baseboard. Nail them to the baseboard with a nail gun and 1½-inch finishing nails, working your way around the room. Anywhere a return is required, make it just as you did for the apron in Step 13.

Step 17: Trim Out the Panels

Miter panel molding at 45 degrees to line the inside edges of the panels. If your molding is delicate, like ours, just glue it in place. For thicker trim, nail it in place with a nail gun and 1½-inch finishing nails. Once all the pieces are installed, fill all nail holes with wood filler, and joints with latex caulk. Let dry. Sand the surfaces, prime the plywood, and finish the project with several coats of paint.

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