Tri-Supply has been making doors for Texans for over 50 years and we’re happy to help you with yours. After choosing from our beautiful interior or exterior door selections, there are a few things you’ll want to know before buying your new door. A quick review of the resources below will give you a great start!
Right-hand, left-hand, right-hand active, left-hand active, inside opening, outside opening; it can be confusing. Fortunately, we can help simplify. There are two reliable ways to get the handing or “door swing” correct.
If you imagine yourself standing on the side of the door where you are pulling it towards you to open it, which ever side the knob is on is the “hand” or “swing” of the door (see diagram).
If you imagine yourself standing inside the door frame with your back to the hinge side and swing your arm the same way the door does, whichever hand you use is the “hand” or “swing” of the door (see diagram).
These methods will work whether the door opens inside or outside. Don’t let double or “french” doors confuse you. The handing is determined from the main operating or “active” door.
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For the entire prehung unit, measure the height and width of your entire door opening, stud to stud, floor to header – called the rough opening. To measure accurately, you might have to remove some interior casing (moulding) to see the backside of the door frame.
For the door only, you just need to measure the door slab width and height. Making note of the bore placements for door knobs, hinge placements and the door thickness may be helpful as well.
Basically what you need here is the stud width plus the thickness of the finished wall. That will be your “jamb” size.
Measuring interior walls vs. exterior walls is a bit different. There are some tools below that will give you a better understanding of how to do this.