Measure each wall at least twice to get the most accurate measurements possible. When measuring outside corners, be sure to add additional room to your measurements to allow for outside corners. You’ll want at least the width of your baseboard in extra room, possibly a bit more.
There are typically three components to most baseboard installations, depending on the type of project. Moving from top to bottom, they include: The cap molding. These moldings fit on top of the baseboards to add a detailed and ornamental flourish. They are typically only needed if you have wainscot paneling. The baseboard. Usually at least 3. 5–6 inches (8. 9–15. 2 cm) high, they are predominantly flat and form the bulk of the baseboard. The shoe molding. Another ornamental detail at the bottom, between the baseboard and the floor, they complete the look. Shoe molding is typically used when you are retrofitting or putting down new flooring.
If the floor is not level, use the level to find the lowest point in the room. Tack a scrap piece of baseboard to the wall at the lowest point. Make horizontal marks every couple of inches in either direction starting at the top of the baseboard, being sure to stay level with this line. Once a few horizontal marks are established, snap a chalk line over the horizontal marks. This will show where the top of the baseboards will stand when they are installed. [2] X Research source
Keeping your compass spread rigid, hold the point-side of the compass on the floor and the pencil-side on the baseboard. Move the pencil across the entire distance of the baseboard to trace an outline. Use a table saw or a jigsaw to cut along the scribed line on the baseboard. If you have a circular saw, set a slight (2° - 5°) bevel on the cut. This will make scribe-fitting much easier in the end. With a block plane, plane down the beveled edge of the baseboard. Then dry-fit the baseboard back onto the floor and make sure it lines up evenly with the chalk line on your wall.
The process is actually fairly simple. Start with a 45° inside cut on the baseboard you want to cope. The other end of the baseboard won’t need to be cut at all; the coped joint will simply cover up the remaining piece of baseboard. Use a coping saw to cut away the angled profile made by your initial 45° cut. The goal here is to leave the paint line intact but cut at a 45° back angle to clear away wood behind the paint line. Go slowly so that you can follow the profile accurately. Sand away any excess rough patches or debris to smooth out the coped seam.
Odd-corner pieces. Where you encounter corners that don’t form ninety-degree angles, use scrap material for trial-and-error fitting until you find the correct angle cut. Then, use that setting on your saw to cut your trim. Mid-wall pieces. It’s likely that you will have to use more than one piece of baseboard to cover very long walls. Instead of simply butting flat ends up against one another, which may separate with time as the wood shrinks, cut both pieces at overlapping 45-degree angles (to fit together like so // ) so that the wood shrinkage will be less visible. End pieces. If the baseboard butts into something and doesn’t need to continue around any corners (ex. it runs into a door casing), simply cut it and scoot it up against the object.
On outside corners, apply a thin bead of wood glue or adhesive to mitered edges to ensure a better bond. On inside corners, adhesive is not necessary if you’ve properly coped your baseboards.
