Things You'll Need
Circular saw, jigsaw or handsaw
Baseboard trim sits at the bottom of the wall to camouflage gaps and gives a room a finished appearance and visual appeal. Attaching baseboard trim with glue rather than nailing it to the concrete substrate prevents the possibility of splitting or splintering the trim when driving fasteners into the concrete. Baseboard trim installation differs depending on whether the floor has an existing covering or you plan to add carpet, tile or wood after the trim molding.
Measure each wall in the room and note the measurements. Cut all trim pieces to size with a circular saw, jigsaw or handsaw equipped with a standard wood-cutting blade. Mark the back of each baseboard trim piece with a marker to identify which wall the trim belongs on, after you make each cut.
Spray the base of the concrete wall with an all-purpose cleaner. Scrub the bottom of the wall with a scrub brush to remove dust and dirt. Wipe the wall with a damp rag and dry the concrete with a dry rag.
Measure baseboard trim's height and mark the height measurement on the wall at each end and in the middle. Stretch a chalk line from mark-to-mark and snap the chalk line to create a level guideline on the concrete wall. If carpet, tile or wood flooring is to be installed later, add 1/2 inch to the height measurement to accommodate the flooring material. Repeat for each wall.
Place construction adhesive into a caulking gun or use a tube of squeezable construction adhesive. Apply a bead of the adhesive to the back of the baseboard trim in a zigzag pattern from end to end, staying 1/4-inch away from the edge of the trim.
Align the top of the trim to the bottom of the chalk guideline and press it in place on the concrete wall. Place 1/2-inch shims under the baseboard trim if you are installing the trim 1/2-inch above the floor to accommodate a future floor covering. Wipe excess adhesive off the floor or wall with a damp sponge. Fold a rag and rub the rag back and forth over the baseboard trim while pressing the trim firmly against the wall. Continue to rub the rag over the baseboard trim until the trim stays in place. Typically, construction adhesive takes less than five minutes to set.
Apply construction adhesive, in a zigzag pattern, over a section of baseboard trim that will abut to the first section. Line the top of the trim up with the bottom of the chalk line, press it in place and rub a rag back and forth over the baseboard trim until it adheres to the concrete wall. Repeat for each wall until baseboard trim covers the base of each wall.
Fill gaps between the concrete wall and baseboard trim with paintable silicone caulk.
Wear disposable gloves when working with construction adhesive.