How to Fasten Trim Moulding

When Fastening Trim Moulding to Walls it is important to attach them to Wall Studs

By Mark J. Donovan

When installing baseboard trim moulding, chair moulding, or crown moulding it is important to fasten it to wall studs. This is particularly true if the trim is expected to hold plates, pictures, clothes, or other objects.

The process of fastening trim moulding to wall studs first involves finding the wall studs. Though this can be a little tricky there are a number of methods at your disposal.

First, you can tap the drywall with you knuckle and as you tap it across the wall you can very subtlety hear a difference when you tap over the wall stud. The sound is less hollow sounding when you are over a wall stud.

If you lack a fine tuned ear then you can alternatively use an inexpensive wall stud finder. A wall stud finder is mainly comprised of a magnet and a pointer that aligns itself perpendicular to the wall when it is slid over a drywall nail or screw.

An alternative to the wall stud finder and knuckle methods is to use a small finish nail and hammer. Using the hammer, tap the small finish nail into the drywall along a section of the drywall to identify the location of a wall stud. When doing this, you want to tap the nail into the wall where the nail holes will be covered by the trim.

Once you find one wall stud, you should be able to use a tape measure to find the others. Wall studs are typically installed on 16 inch centers.

How to Fasten Trim Moulding

Another stud finder tip is to look where the wall outlets are placed. The electrical boxes are usually fastened to wall studs.

In addition to making sure you fasten the trim moulding to the wall studs, it is important to use the right nails. Typically you want to use a finish nail that will penetrate the wall stud approximately 1.5 to 2 inches.

When accounting for the width of the trim, e.g. ½ inch, and the drywall, which is also typically ½ inch, you need about a 2.5” to 3” nail to properly fasten the trim moulding to the walls. A 2.5” nail is referred to as an 8d penny nail and a 3” nail is referred to as a 10d penny nail.

Once you have found the wall studs and have purchased the right nails, fasten the trim moulding to the wall using a hammer. Hammer the nail into the trim moulding until it is about ½ inch from the surface of the trim.

Next use a nail punch, along with your hammer to set the nail just below the surface of the trim. Alternatively you can use a nail gun, which will automatically set the nail just below the surface of the trim moulding.

Finally patch the nail with wood filler. When the wood filler is dry, lightly sand it and the trim moulding is ready for paint, stain and/or polyurethane.

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For information on installing Window and Door trim see’s  Installing Interior Window Trim Ebook and  Installing Interior Door Trim Ebook.  These Ebooks are loaded with pictures and provide easy to understand, step-by-step instructions, on how to install interior window and door trim.

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