Features
On the House
Wall framing
After more than a decade as a Boy Scout, one of our sons soon will achieve that organization’s highest rank — Eagle Scout.
In order to attain that rank, in addition to many other requirements, a boy must earn certain merit badges and perform a service project in his community. Recently our families had an opportunity to participate in an Eagle project. It involved the construction of a windbreak wall and the extension of a roof on a small feed barn for horses at a nearby state park.
We created a plan, made up the materials list and helped the boys measure, mark, cut and nail the wood that was used to create the wall and roof. It was a fulfilling experience for all involved — scouts and adults. Scouts learned about carpentry and the park ranger was thrilled with the completed work.
When the boys learned that the walls in their homes were constructed in essentially the same fashion, they became even more interested.
If you are planning to remodel or add on, you might find it helpful to know a bit about the ins and outs of wall framing. Perhaps you have visions of knocking down a wall between two bedrooms to create one larger room with a walk-in closet. Or, maybe you want to make an opening in an existing wall to install a door or window.
A wood frame wall is a collection of vertical framing members called studs (2x4 or 2x6) — equally spaced (usually 16 inches or 24 inches on center) and sandwiched between top and bottom plates. The top plate can be either single or double. A double top plate or “doubler” is used to add strength and stability to the wall. The added strength of a doubler is especially important for a “bearing” wall — where the wall supports floor joists, ceiling joists or roof rafters. The joint in a doubler should be located at least 4 feet from any joint in the top plate.
The bottom plate or “sole plate” is single thickness and is fastened to the subfloor. In the case of a concrete slab, the bottom plate consists of pressure-treated material to prevent rot. Aside from studs and plates, the other components of a wood-framed wall are headers, trimmers, sills, corner assemblies and diagonal bracing. A header is placed at the top of a rough opening where a window, door or archway will exist. A header can consist of one solid piece of lumber or it can be fabricated out of several pieces, depending upon the span and structural configuration.
A fabricated header usually is made of two pieces of 2-by material with a half-inch spacer sandwiched between them. The spacer brings the width of the header to 3 1/2 inches — the actual width of a 2x4.
A header is supported at either side of the opening by a “jack stud” or “trimmer.” The trimmer is nailed to the header and a “king stud.” The king stud is a full-height stud nailed to each end of the header. When the header is other than one solid member, short pieces of 2x material called “cripples” are installed between the top of the header and the bottom of the top plate. Cripples also are used below the rough windowsill and the sole plate. As with studs, all cripples must be installed on “layout” to ensure that manufactured material such as siding and wallboard will have backing at all joints.
No matter how well-built a wall might be, without proper diagonal bracing (and structural shear where required), it can collapse like a house of cards. Diagonal bracing usually consists of a 1x4 that is cut into or “let in” to the wall framing. Metal straps nailed to the face of the wall framing have become increasingly popular in recent years.
Corner framing requires special attention for two reasons — structural integrity and solid backing to form an inside nailing corner. There are two popular corner construction configurations — three studs and two studs with blocks. We prefer using two studs with short blocks between them. The end stud at the adjacent wall is then nailed to the sandwiched corner.
While you might already have your hammer in one hand and a handful of nails in the other, we suggest that you first nail down a couple of issues before banging away. Don’t make any structural changes to your home without consulting an engineer. And be sure to check with your local building department to determine if a permit and inspections will be required for the work. A permit is for your safety and the safety of your family and neighbors.
For more home improvement tips and information visit our Web site at www.onthehouse.com.