Installation Guide

How to Install Flat Stock
Flat Stock is a wood trim with many application usually applied to a doorjamb. It creates a finished frame for the doorjamb and
conceals the perimeter shim space used to secure the doorjamb to the adjacent wall framing on both the exterior and interior of the
door. This will create the finished look for your door unit. It can also be used as a jamb extender, brick spacer, interior/exterior trim,
and a variety of other trim applications in conjunction with your Main Door Installation.
Things You'll Need
Tape measure
Finish hammer
Wood glue(optional)
Miter saw/trim saw
8d finish nails
Nail set
Stainable Filler/Finish
Instructions
1. Use a tape measure and pencil to mark the edge of the doorjamb, ¼ inch from the door opening. Make the first mark at the
bottom of the jamb on the strike side, opposite the hinge side, and repeat at approximately 12-inch increments around the
perimeter of the jamb. These marks will define the 1x4 setback, called the reveal, and guide the attachment of each piece.
2. Measure the distance from the bottom of the jamb on the strike side to the bottom of the horizontal headpiece at the top of the
jamb. Mark this measurement plus ¼ inch on a length of flat stock, ensuring the end from which you measure is cut square and you
mark what will be the inside edge of the flat stock piece.
3. Set your miter saw to a 45-degree angle (or at a 90-degree angle for a butt joint) and cut the flat stock piece marked in Step 2, so
that the measured mark is the short point of the miter cut.
4. Position the piece of flat stock cut in Step 3 against the edge of the doorjamb and align it with the ¼-inch reveal marked in Step 1.
Be sure the short point of the miter cut at the top extends ¼ inch beyond the bottom edge of the top jamb. Attach the flat stock at
each mark with a 8d finish nail. Use wood glue rated for exterior applications if desired.
5. Open the door and measure the horizontal dimension between the inside faces of the doorjamb at the top.
6. Mark a piece of flat-stock with the measurement determined in Step 5 plus ½ inch. Position the marks on the flat stock piece to
allow them to be the short points of opposing 45-degree angles at each end of the piece. Cut both angles with the miter saw.
7. Position the flat stock piece cut in Step 6 at the edge of the head jamb and align it with the ¼-inch reveal marked in Step 1.
Attach the head piece at each reveal mark with a 8d finish nail. Glue if desired.
8. Repeat Steps 2, 3 and 4 for the remaining jamb piece on the hinge side of the doorjamb.
9. Nail the outer edge of the flat stock pieces into the adjacent wall with 8d finish nails spaced 12 to 16 inches apart around the
perimeter to hold the flat stock edge tight against the wall surface.
10. Repeat Steps 1 through 9 for the flat stock on the opposite side of the doorjamb. Use a nail set to set all of the nail heads 1/16
inch below the flat stock surface. Fill and Finish the nail holes.
Main Door does not accept any responsibility nor does it offer any warranty for the information provided herein. These instructions are provided as a general guideline. Please seek
additional information if you have questions or seek the advice of a licensed professional carpenter.