How to Replace Door Trim on a Pre Hung Door - Trim Carpentry

Door trim upgrades will add value to your home, but replacing door trim on a pre hung door is tricky unless you follow the right steps. Watch step-by-step how to replace door trim on a pre hung door using trim carpentry techniques. The first step to separate the door trim from the drywall using a sharp utility knife. Then, do the same between the door jamb (the inside frame of the door) and the trim. Before you start taking off the door trim though, it’s important to take it off in the right order. A pre hung door is a preassembled unit, including the door, door jamb, and trim. It’s installed by standing up the pre hung door in the opening and nailed in place through the trim. This is a method of trim carpentry for fast production work. If you take off all the trim at once, the door jamb will move and will be difficult to control. Start by only taking off the top piece of trim. Once the top piece of trim is removed, shim up the corners of the door jamb and drive in some finishing nails to hold it in place. This will lock the top of the door jamb in place. The second piece of trim to remove is on the hinge side of the door. It’s important to shim this up at the hinges and in the middle so the door is positioned with an even gap at the door opening side. Drive in some finishing nails to hold this side of the door jamb in place. You can now remove the door trim on the last side. Shim and nail it in place in several spots, including where the strike plate is for the door latch. Now you’ve locked the door jamb in place. The trim on pre hung doors is glued and stapled to the door jamb. It’s difficult to remove in spots. I use a putty knife to remove as much as I can. I use fencing pliers to remove the staples, then remove any remaining trim with a sharp chisel or block plane. Installing the new trim starts with the plinth blocks at the bottom of the door frame. Once the plinth blocks are installed, it’s time to measure the length of the casing by standing it in place and marking where the old trim was removed at the top. I also measure the length of the top cap to build in the workshop. The top cap is made up of three parts; the header, a 1/2 round trim, and a small crown moulding. After cutting a 1x6 board to length on the miter saw, I cut a small piece of 1/2 round with a 45 degree miter and the longer piece with a matching 45 degree miter. I test the fit on the cap board and glue them together with CA glue to get a bond in seconds. I then measure the length I need for the second miter and cut it to length. I attach this to the cap board using CA glue and PVA/Carpenter’s glue. I follow a similar process for the small crown on the top cap. After sanding and priming the assembled top cap, it’s ready for installation. After cutting the trim to length, I nail on the side that will be most visible first. Then I stand the second side in place and nail it on at the bottom and the middle, leaving the top loose. I then nail on the top cap by alining it to the most visible side first, then I can adjust the loose door trim to align with the top cap and nail it in place. I hope you enjoy this video and learn a few new things about trim carpentry. It can be rewarding work to transform your home with trim. MITER SAW DUST COLLECTION HOOD PLANS RELATED VIDEOS Bedroom Remodel Project Play List - Closet Door Upgrade to Replace Sliding Doors - Closet Organizer Build - How to Install Door Trim on Closet Doors - 10% off STARBOND CA GLUE LINK Use Coupon Code “WIBN“ for 10% Discount - Note: purchases made with this link help support our video production work VIDEO TOPICS 00:00 How to Replace Door Trim on a Pre Hung Door 00:59 Separating the door trim from the drywall and door jamb 01:59 Removing the door trim at the top of the pre hung door 03:13 Securing the top of the pre hung door in place 04:19 Shimming the door hinge side 05:56 Shimming the door opening side 07:39 Measuring the door trim 10:14 Building the door cap 28:52 Installing the door trim Our Newsletter - Sign up at Our Woodworking Plans - Our 1-on-1 Woodworking Advice Sessions - See the tools we use in our workshop and the tools we recommend: 🇨🇦 Canadian link - For more woodworking knowledge or to contact us directly, visit our website Hosted by Scott Bennett, owner of Wooden It Be Nice in Brooklin, Ontario, Canada #Trim #Carpentry #Door