When we were carpenters, our most common side-job was creating openings in walls. We'd cut out the wallboard, remove several studs, install a "header" (a beam to hold up the ceiling and roof), install supports to hold up the header, patch the wallboard, and occasionally, install a door into the opening. It is just that easy. But, there are tricks that can make the job even easier.

An experienced eye can determine what is needed to safely create a new opening in a wall. For safety, it is wise to get a building permit for this project. Although they are not engineers, building officials know all the right questions to ask. They often can tell you whether it is safe to proceed, or whether an engineer will be required.

You can pull a bearing wall out of a building and might not begin to see the effect for days, weeks or even months. But once whatever was previously supported starts to come down, you won't believe the amount of damage that can occur.

First, some stud-wall nomenclature:

*Bottom plate (or sole plate): The horizontal framing member at the bottom of the wall that attaches to the bottom of the studs and to the floor.

*Double top plate (or double plate): The horizontal framing member at the top of the wall that attaches to the studs and to the ceiling and-or roof framing above.

*Studs: The vertical framing members that travel from the bottom plate at the floor to the double top plate at the ceiling.

*Header: A large timber placed horizontally along the top of a wall (usually, immediately beneath the double plate) to support the weight bearing down from above when studs must be removed to facilitate an opening.

*King stud: A stud nailed to the end of the header that travels from the double plate to the bottom plate. To be the king stud, it must travel from plate to plate and be immediately next to the end of the header.

*Cripple stud (or cripple, or jack stud or trimmer): It is not a full height stud, but is a load-supporting stud that travels from the underside of the header to the sole plate and is sandwiched together with the king stud.

*Diagonal bracing (angle blocking or let-in bracing): Used to support a wall during the construction stage. Diagonal bracing has no structural value other than to help keep a wall in place during the framing stage. Cutting through angled braces or removing angled blocks doesn't compromise structural integrity.

Now that we've covered wall anatomy, we'll discuss an equally important element..."structure"...or how to build an opening into an existing wall without having the roof cave in. Some walls support things above, and some don't. Walls that support loads are called load-bearing - or bearing walls. Walls that don't carry a load are termed nonbearing. If a bearing wall contains a window or door opening, a beam is used to span the top of the opening, replacing support provided by the studs that are removed to allow for the opening.

The amount of the load on a wall and the width of the opening will determine the size of the header needed. We like solid headers that are equal to the thickness of the wall and that travel from the top of the new opening to the double plate. For a normal opening in a 2x4 wall, a 4x12 header meets our criteria. For most small openings, a 4x12 is overkill, but when it comes to installation time, a 4x12 can be a big timesaver. A structural engineer or your local building department can help here.

Once it has been determined that the opening can be built, there is a procedure that we use to save time, and, therefore, money. The trick is attaching our new header from existing stud to existing stud. This usually means using a header that is longer than the planned opening by as much as a foot. It makes the installation easy.

The steps:

*Mark your opening on the wall.

*Next, remove the wallboard on one side of the wall only: remove the wallboard back to the first existing stud that clears either side of the planned opening. These existing studs will be used as the king studs for your new opening. The wallboard opening will end up being a foot or two wider than the opening you plan to create. The wallboard must be removed from floor to ceiling.

*Next, cut a header to fit. Measure the distance between the existing studs that are on either side of the new opening, and cut your header to fit between them. Lay it aside.

*Next, cut a pair of cripple studs. Measure the distance between the bottom plate and the top plate and subtract the height of the header. For example, if the total distance between plates is 92 inches and the header height is 11 inches, the measurement would be 92 minus 11 or 81 inches. Cut two new studs each to a length of 81 inches. Lay the cripples aside.

*Next, remove the studs that exist between your newly designated king studs. Do not remove the studs that will be used as the king studs. Bend the nails that protrude down from the top plate and up from the bottom plate. Flatten them into their respective plate.

*Next, install the header and cripples (you will need a helper). Each person grabs one end of the header and a cripple. Using muscle and a hammer, tap the header into position. Wedge the cripple between the header and the sole plate as a support (angle the cripple, if necessary). Caution: The header can hurt if it falls on your head. Tap the cripples on both sides so that they fit snugly against their respective king studs.

*Next, nail everything together with 8d sinkers and use metal straps at all connections.

*Finally, cut and place a second set of cripples that will be used to make up the sides of the actual opening. Once these are in place, the wallboard at the other side can be cut out to the opening size. At this point, the bottom plate also gets cut. Toenail the end of the bottom plate to the floor. Use two 8d sinkers toe-nailed into each end.

At this point, you can patch the wallboard wrapping around the inside of the new opening. Or leave the inside of the opening unfinished and ready for hanging a door or wood trim, which can be done once the wallboard repair has been completed.

Sometimes creating an opening can get complicated. Walls can contain water or sewer pipes, ducting, electrical wiring and more. Although these conditions raise the cost and extend the time of completion, they rarely prevent the task from being performed. In some situations rethinking the opening location can save a lot of money.

*Caution: If wallboard is removed and plywood is discovered, it could mean that an opening cannot be created in the wall. Remember what we said about a permit or talking to a structural engineer? Also, in some instances double king studs and-or double cripple studs are required. Also, additional supports might be needed beneath the floor. This can be a problem when an opening is planned on a second floor. A structural engineer and maybe even your local building inspector can help you do the planning.