by Don Dunkley I've been framing custom homes for more than 25 years, and I've learned that a well-planned layout is the key to an efficient job. Errors are bound to occur: Clients are unpredictable, general contractors can forget to relay important details, framers are always in a hurry, and plans are often inconsistent. A job hindered by mistakes and changes goes slow, costs money, and becomes discouraging for everyone involved. But with a little planning and a well-detailed layout, I can often avoid these problems by following these layout rules.

RULE 1:Study the Plans I don't just roll up to a site, pull out a crisp set of unread plans, and pound away. Before I get to the site, I thoroughly review the plans and mentally put the frame together. I study the roof frame first to determine my stud heights. I check the interior ceiling elevations, looking for any balloon frames and rake walls. I find all the beams that need to be installed. I study the elevations, looking for any conflicts. Failing to check for design errors at this stage is an invitation to a framing disaster.

Plan quality.Layout is always a challenge, and the quality of the plans plays a big part. Due to the high cost of hiring professional architects, builders can often get saddled with inadequate residential plans drawn by poorly trained building designers. Some of the designers I work with do excellent work, but many provide plans without specification sheets, with scant section views, and with inconsistent dimensions. The general contractor and the framing contractor usually wind up spending hours together making these half-baked plans work. I recommend the good designers whenever possible. But if my clients opt for someone else, I won't hesitate to tack on extra money at the bid stage for working with crummy plans. Once I have a basic understanding of how the frame will go together, I examine other critical details, including windows, interior trim, exterior finish, and structural requirements. As I gather the information I need, I write it directly on the layout pages of a set of job-site plans. And because the job site wreaks havoc on plans, I mark up an additional set of plans to keep at the office for future reference. Armed with a freshly marked set of plans, with no questions left unanswered, I'm ready to snap some lines.

RULE 2: A slab or subfloor is almost never perfectly square, so the first thing I do is establish a set of square reference lines (see ). Using a couple of 100-foot tapes and a calculator, stretch two dry lines along the edges of a corner of the deck, set back twice the width of the future wall plates. I look for an outside corner where the two longest walls meet so the diagonal will be at least 30 feet. If the perimeter of the deck is too chopped up, I square the lines off a long interior wall.

Plug the length dimensions into a Construction Master and calculate the diagonal, then adjust the lines until the measured diagonal matches. Now find out how far out of whack the deck is by measuring from the edge of the deck to the dry lines. If needed, move the lines so the bottom wall plate will hang out over the edge of the deck a little, being careful to keep the lines square in relation to each other. When the lines are where you want them, measure toward the edge of the deck the width of the wall plates and make a set of marks, then snap the lines. You can now use this set of square base lines to pull all of the other dimensions. Exterior dimensions. After my base line is set up, I snap out the exterior walls. The important thing here is to make the exterior dimensions match those on the plans as closely as possible. This is especially important on a house with roof trusses, because the truss manufacturer is building from plans received a month or so ago, not from what's built on site. For a house with a truss roof, I keep the exterior walls within 1/4 inch of the plan. There's a little more wiggle room with a stick-built roof, which can be cut to fit whatever dimensions the exterior walls get framed. Once I have the outside dimensions under control, I move on to the inside walls.

RULE 3: Lay Out With Trim in Mind Don't overlook interior trim during framing. Before I start my layout, I find out what size trim will be installed. If it's not yet defined, I push the general contractor and client to choose the trim.

Hallways are typically planned small or get squeezed tight to make room elsewhere. The first place I look is the end of a hallway, where I'm almost sure to find the largest possible doorway being crammed into the narrowest possible space, leaving room for only the skinniest whisper of trim. Casing ends up being shoved tight to the drywall with no reveal, or worse, must be ripped down to fit. Knowing my casing size in advance, however, I can snap out the hallway to work for my trim. For example, to lay out enough room for a 2-foot 6-inch door with, say, a 2-1/4-inch door casing, the minimum hallway width required is 38 inches before drywall (Figure 2).

Figure 2.When framing a doorway in a narrow hallway, make sure there's enough room for casing. When using wider casing, the author adds an extra king stud where necessary. This leaves room for a king stud and trimmer on either side of a 35-inch header, resulting in a 32-inch R.O. with 2 inches for the jamb and some shim space. Once drywall is on, a 1/2-inch reveal remains between each edge of the casing and the wall. For 3-1/2-inch casing, I'll make the hallway 41 inches wide to leave a nice reveal. When "detailing" (see ""), I mark an additional stud alongside the king stud for extra nailing for the trim. Another tight spot is a bedroom door in a hallway that opens right against a perpendicular wall inside the room. To gain wall space in the bedroom, the designer typically crams the doorway tight to the adjacent wall. From the hallway side, there may be plenty of room for casing, but it's often a squeeze on the other side. In this case, measure from the inside corner the width of the casing, then add the drywall and the reveal. To keep the door tight to the wall but still leave a minimum reveal with 2-1/4-inch casing, plan for a single king stud. Bathrooms are typically small and filled with lots of stuff. Often, a bathroom wall must fit both an entry door and a vanity (). To accommodate these, mark the vanity edge at 21 inches for the cabinet plus 1 inch for the counter nosing and 1/2 inch for drywall - a total of 22-1/2 inches. To leave room for 2-1/2-inch casing and a pleasing 1-1/4-inch reveal, mark the face of the king stud at least 24 inches from the wall. Check to see if the door will fit (don't make the door less than 2 feet 6 inches). If it looks like the casing will get hacked, widen the room. Kitchens. Most kitchen base cabinets are 25 inches wide including the counter nosing. When a door has been placed tight to a cabinet, I allow a minimum of 27 inches from the intersecting rough-framed wall to the face of the king stud. This gives just enough room to fit in the casing.

RULE 4: Know Your Windows and DoorsThere's nothing quite so unsettling as realizing that the pile of windows that just arrived on the job site won't fit the framed openings. Before starting any job, make sure to confirm the window manufacturer's specs.

Window R.O.. Most of the windows I install are aluminum or vinyl. Like wood and clad windows, they differ in size from manufacturer to manufacturer, typically ranging from 1/2 inch under to 1/2 inch over the window dimensions called out on the plans. A call-out for a "3040" window (meaning 3'0" x 4'0") might require a 35-1/2x47-1/2-inch R.O. or a 36-1/2x48-1/2-inch R.O., or something in between. A call to the manufacturer is the best way to be sure. In some cases, the call-out matches the R.O. exactly. But if there's any difference, I'll mark the correct opening size on the plan ahead of time to use when detailing. Even if the plans include a spec sheet for wood window sizes, check them out beforehand. Don't count on them to be accurate. The burden of finding out the windows' proper R.O. falls to the framing contractor. If you don't check ahead of time and the openings turn out wrong, you'll be fixing them on your dime. Plenty of windows these days include half-round arches, elliptical arches, and transoms. Some are stacked on top of each other or mulled together. When the elevation shows such specialty windows, I always make a call to the supplier and get the low down on how to detail the rough openings. Egress. Even though all plans must be issued through a local building department for plan check, it's cheap insurance to double-check that all the bedroom window openings meet egress code. Remember, too, that any window that comes within 18 inches of the floor requires tempered glass. I always bring this to the client's attention, in case they want to raise the window sill height and save a few bucks. When detailing the window locations on the framing plate, stay aware of local code requirements for a window's proximity to a gas meter. More often than not, the actual gas meter location will be different than what's indicated on the plans, or not noted at all. Window changes. Nothing ruins a day like hearing the clients say, three weeks into a job, "We want wood windows instead of aluminum ones." The rest of the day gets spent yanking out headers and sills on a sheathed two-story wall. I try to nip this in the bud by insisting that the windows be a firm decision before layout stage - "no take-backs." Most clients don't realize windows aren't usually interchangeable by size, type, or manufacturer. To detail a standard window header, I add 3 inches to the R.O width. This accounts for the two trimmer studs. If the window or door opening is greater than 6 feet, the standard rule of thumb calls for double trimmers. Engineering may require an increase in header size, or a change to 4-by trimmer studs, so I always review the calc sheet attached to the plans (a requirement in California, where I work). Recessed windows. I also check the elevations for recessed windows, common in stucco exteriors. Sometimes the floor plans show a standard opening, while the elevation shows a recessed detail. Recessed windows need extra framing, and the headers can easily run an additional 6 inches in length (). To detail door headers, I add 5 inches to the door call-out. For example a 3-foot 0-inch door requires a 41-inch header. This accounts for two trimmers, the door jamb, and shim room. Pocket-door rough openings need two more inches in height than standard 6-foot 8-inch doors. On the West Coast, it's common to use solid 4x12 material as header stock for standard doors, and 4x10s for pocket doors. The R.O. width of a pocket door is figured by doubling the door width and adding 5 inches. For example, a 2-foot 8-inch pocket door has a 69-inch-long header (32 inches + 32 inches + 5 inches). Most of the closet door openings I frame are for bypass sliding doors. The R.O. is 1 inch smaller than a standard opening of that size, allowing the two doors to overlap. For example, while I'll frame a standard opening for a pair of 2-foot 6-inch doors using a header length of 65 inches, I'll cut the header to 64 inches for a bypass door.