How To: Install Picture Frame Molding
Sep 7th, 2009 by Sarah
We’re just finishing up a project to install picture frame molding below the existing chair rail in our dining room. Thought I’d post what we did to install it in case it’s useful to someone else.
Step 1
Decide on the spacing to use for the picture frame molding so that it’s fairly consistent & symmetrical around the room. Don’t worry too much about the placement of outlets, etc. in relation to where the molding will go.
For our dining room, since the chair rail is so low, we decided to use the following spacing for long, skinny rectangles on the wall:
- 2″ from the bottom of the chair rail to the top of the picture frame molding
- 2″ from the bottom of the picture frame molding to the top of the base board
- 4″ between vertical pieces of picture frame molding and corners, door casing, etc.
For help visualizing what would look right, use painters tape where the molding will be. (Just remember to remove it relatively soon to avoid damage to the wall!)

Painters Tape to Visualize Spacing
Step 2
Use a compass to draw guide lines on the wall where the molding will go. These lines should be parallel to any existing trim, etc. in the room.

Draw Guidelines for Molding
Step 3
Using the guide lines drawn on the wall, individually measure the exact length needed for each piece of trim.
We found that it’s not uncommon for each side of the frame to be a slightly different length, most probably because the house is old and not everything is exactly square. We decided it was more important that the frames look level and square on the wall next to the existing trim rather than that they actually are level and square, so we used the exact measurements taken from the wall for each piece rather than assuming anything.
Step 4
For each piece measured, cut the ends of the molding at a 45 degree angle. For this, we used a compound miter saw. Even though our frames weren’t completely square in some cases, we only had one where we had to modify the angle from 45 degrees.
In the case where an outlet was positioned in the path of the picture frame molding, we cut it at a 45 degree angle and left a gap of about 3/4″ between the edge of the molding and the outlet covers.

Molding Around Outlets
Step 5
Starting with the top side of the frame, attach the molding to the wall with construction adhesive and a nail gun so that it’s aligned with the guide lines. After the top side is attached, install the two vertical pieces of molding, followed by the bottom piece. For each piece, we found it really helpful to test fit first to make sure the length and corner miters aligned correctly.
Our walls are plaster and we were concerned at first about using a nail gun for fear that it might cause the plaster to shatter. We tested in a closet and didn’t have any problems, so we decided to use it for attaching the molding. It worked great, with no damage to the wall, but we found that the construction adhesive was still needed to help the molding stay attached to the wall in the places where the wall was a little wavy.

Attaching the Molding
Step 6
With all of the molding attached to the wall, fill the nail holes, sand the edges off of the molding, and apply caulk around the edges of each frame to fill in any gaps between the molding and the wall. We also used a really small amount of caulk to help fill in and smooth out the corners of the frames.
Step 7
Prime and paint the walls & new molding.
Since our walls were plaster, we needed to prime the walls with a concrete primer and the molding with a wood primer. If we do this project again, we’d probably choose to prime the walls and molding before installing the molding to avoid all of the cutting in that was needed for the 2 different types of primers.
We chose to paint our picture frame molding and the wall behind it a semi-gloss enamel in the same color as the rest of the trim in our house. For the outlet covers, we bought some unfinished wood ones that are being primed and painted the same color as the molding so they’ll blend in nicely.

Painting the Picture Frame Molding




















