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How To Apply Door Casing Article
8. How to Apply Door Casing
from:Appling a new door casing to finish out a new room or re-finish an existing room is easy and can change a room’s appearance. If replacing an old casing, carefully remove and discard the old material.
To install a new casing, you must measure for the inside of the door frame, on the wood casing, and make a mark a 1/8” from the inside all around the door frame. This is to give the finished door a 1/8” reveal between the door and the casing. Now measuring from this 1/8” mark on the top to the floor; record this and transfer this measurement to your new casing, it is always good to measure twice and cut once. Remember this will be the shortest point on the casing when cutting the 45 degree angle, so it is best to mark the inside edge of the casing. Using either a hand or power miter box, cut at the mark at 45 degrees. NOTE: It is best to cut the opposite end first to make sure it is nice and square before making the finished measurement. After this is cut, measure across the top and only cut the 45 end that will mate with the first piece. This is to align the two pieces without nailing them, just in case the angle is not exactly 45 degree. Dry fit the two pieces to make sure you have a tight mitered corner and adjust as needed, then re-measure and cut the opposite end of the top casing.
When the miters appear to be tight, apply some wood glue to the surfaces of the mitered ends, and nail the casings to the jambs using 4D (4 penny) nails at least 1 inch back from the miter. You may want to drill pilot holes for the nails before nailing, to avoid splitting the wood. Measure and cut the last side, if you have any scrap pieces, you can cut the 45 degree angle and test to make sure the miter is again tight, and adjust the angle cut as needed to cut the final piece. To make sure the corner miters remain tight, carefully nail from the top piece of casing down into the side casing. It would be best to pre-drill and take care so you do not split the casing in the corner. Repeat this from the side of the casing nailing into the top casing.
When one corner is complete, repeat for other corner, when it is completely hung. Nail the last side in place with wood glue on the mitered surfaces, again using 4D nails. Use a nail set and hammer to set the nails slightly below the finished surface. If you are painting, use a filling compound such as Spackle to fill the nail hole. If you are staining, use a wood filler appropriate to your finishing technique.