How to Widen a Doorway in a Bearing Wall Safely

Why this matters

The bathroom door is usually the one a walker or a wheelchair cannot get through, and it is often in a wall that holds up the floor or roof above. Widen it as if it were a partition and the first sign is a ceiling crack over the new header a month later, then a bedroom door upstairs that will not latch, then a floor that dips at the doorway. The opening itself is an afternoon of carpentry. Everything that makes it safe happens before the first stud is cut and below the floor after it.

Whether you can gain the width without opening the wall (offset hinges, removing the stop) is a sibling's subject: see related, How to Measure Clear Width and Gain It Without Widening. Do that check first; widening is the answer left standing after the cheap ones fail.

Step 1: Open an inspection hole before you decide anything

Before you quote, cut a hand-sized hole on the hinge side of the opening, near the floor and near the ceiling, to see what is in the wall.

• De-energize first. Turn off the circuits feeding the switch and any receptacle on that wall, lock the breaker, and prove the box dead on a known live source before and after (live-dead-live, per NFPA 70E Article 120 (120.5 in the 2021 edition, renumbered in 2024), with work practices at 29 CFR 1910.333(b)(2)). A switch beside a door is often on a different circuit than the outlet below it, so test each one.
• Disturbance hazard. In a house built before 1978, assume the paint is lead until a test says otherwise. Cutting or demolishing more than about six square feet of painted interior surface in pre-1978 housing brings the work under the EPA Renovation, Repair and Painting rule (40 CFR 745 Subpart E) at the federal layer, with several states running their own stricter programs: a certified renovator, containment and cleaning verification. Joint compound and plaster from roughly the same era can contain asbestos; if the wall is plaster or the compound is suspect, have it sampled before it is cut. Drywall and plaster dust carry respirable silica as well, so cut with a shrouded saw and vacuum extraction, and wear a respirator only under a written program per 29 CFR 1910.134.

A drain stack, gas line or supply duct in the bay beside the door adds a trade to the quote. Finding it after the wall is open is how a two-day job becomes a two-week one with the only bathroom out of service.

Step 2: Prove whether the wall bears

Do not assume either way. Read the structure above and below the wall:

1. Look above. Joists or rafters running perpendicular to the wall and lapping or splicing over it bear on it. Joists running parallel usually mean a partition, unless a beam or girder truss lands on it.
2. Look below. A bearing wall usually sits over a beam, girder, foundation wall or line of posts.
3. Look for a point load. A doubled or tripled stud, a buried post or a beam pocket above means something concentrated comes down there, and it is the most common reason this job needs an engineer.

The fork. If the joists run over the wall, it bears, and you proceed with Steps 3 to 6. If you find a point load, a girder truss, a beam end, or the wall is on the lower floor of a two-story house carrying another bearing wall directly above, stop and bring in a structural engineer. Walk in with photos above and below, joist direction, size and spacing, the existing and proposed widths, and where anything concentrated lands. You walk out with a sized header and a stamped detail.

Step 3: Size the header from the code's tables, or from the engineer

A header is the beam over the opening. It carries the load that used to come down the studs you are removing and moves it sideways to the jack studs (the shortened studs under each end of the header) and then down to the floor.

For conventional wood framing in a one- or two-family house, the header comes from IRC Section R602.7 and its span tables, as adopted by your jurisdiction (Tables R602.7(1) and R602.7(2) in the 2018 and 2021 editions; check the numbering in the edition your building department uses). Write down four inputs before you open the book:

• What the header supports: roof and ceiling only, or one floor plus roof, or two floors.
• Building width: the dimension perpendicular to the ridge, which sets how much floor or roof tributary load lands on this wall.
• Ground snow load for your area, from the jurisdiction.
• The span: the new rough opening width, not the finished door width.

The table returns a header size (for example, a doubled or tripled member of a given depth) and the number of jack studs required at each end. The jack count matters as much as the header: a single jack crushed under a heavy header is a common cause of the slow sag that shows up months later.

Engineered lumber (laminated veneer lumber and similar) is sized from the manufacturer's published span tables, not the IRC's sawn-lumber tables. If your span or load falls outside every table you have, that is the engineer, not a judgment call.

Step 4: Pull the permit before you shore

Cutting a bearing wall is a structural alteration, which needs a building permit in most jurisdictions (IRC R105 as adopted; local exemptions for minor work almost never reach structure), with the header size on the application. The switch move rides on an electrical permit or the same one, depending on the department. The inspector will usually want to see the header and jacks before the wall closes, so schedule that visit and tell the customer the wall stays open until it happens.

Step 5: Shore, then cut

Temporary shoring carries the load while the studs are out. Build it before you remove a single stud.

• Where: a temporary stud wall with a top and bottom plate, set about two to three feet back from the bearing wall, on whichever side the joists above bear. If joists land on the wall from both sides, shore both sides.
• How tight: snug the studs under the top plate with shims or a tap. Do not jack the ceiling up. Lifting even a fraction of an inch cracks the plaster and drywall you are trying to protect and can lift the floor above off its own supports.
• What it bears on: the floor below the shoring wall has to carry the load too. On a basement slab that is easy; on a suspended floor, put the shoring over or near a joist line or add a temporary post below.

Hazard while it stands: shoring gets knocked by someone carrying a long board more often than it fails on its own. Flag it and tell everyone in the house not to move it.

Then cut. Remove drywall to the new rough opening plus a stud bay each side, cut and remove the studs within the new opening, install new king studs (full height, beside the jacks), jacks, the header and cripples (the short studs between header and top plate). Nail the header through the kings and the jacks to the header per the fastening schedule in the code (IRC Table R602.3(1) as adopted). Only when every jack is bearing fully on the sole plate and the header is fastened do you remove the shoring.

Resume step, with its check. Before you pull the shoring, sight along the header and the ceiling for deflection, confirm no gap between jack tops and header, and confirm the load path below: the jacks now concentrate the wall's load at two points, and those points need something under them. If a jack lands between floor joists with nothing below, add solid blocking down to the beam or wall below before the shoring comes out. Then remove the shoring studs one at a time, watching the ceiling line.

Step 6: Move the switch and the outlet

Widening almost always puts a switch box inside the new opening or the new king stud. You have three ways to move it, in order of preference:

1. The existing cable has slack. Nonmetallic cable is secured within 12 inches of a box (NEC 334.30), so slack is rarely more than that, but sometimes it reaches the next bay.
2. Run a new cable from the last accessible box. Pull a fresh run from the previous device or from the attic. This leaves no new splice in the wall.
3. Extend with a splice in an accessible junction box. Every splice must be in a box that stays accessible after the work (NEC 300.15 and 314.29, as adopted). A box buried behind the new drywall is a code violation and a future fire nobody can find.

Check box fill (NEC 314.16) on the new box, keep the switch on the latch side of the new door, and set its height to what the person can reach, not to the house's old 48 inches; see related, Reach Ranges and Control Heights. Extending a branch circuit can trigger arc-fault protection in the editions of NEC 210.12 most jurisdictions now enforce, so check before you quote it.

Resume step: before you restore the breaker, confirm every splice is made up and boxed, every device is mounted and covered, and no conductor was nicked by the saw. Restore with the cover plates on and stand to the side of the panel, then test the switch and outlet with a tester rather than assuming.

Worked example: a 28-inch bathroom door to a 36-inch one

A homeowner who now uses a walker, and expects a wheelchair within the year, cannot get through her bathroom door. Measured clear width with the door open 90 degrees, from the face of the door to the stop on the latch side: 25.5 inches. Removing the stop and fitting offset hinges was checked first and gets her to about 27.5 inches. Her occupational therapist wants at least 32 inches for the chair she will be fitted with, the figure the 2010 ADA Standards use at 404.2.3 (a reference, not a requirement, in a private home).

A 36-inch door gives roughly 32 to 33 inches of clear width depending on the door thickness and stop, so 36 is the door. That puts the rough opening at about 38 inches against the existing 30.

Inspection hole: one switch box on the latch side at 48 inches, fed from the ceiling; no plumbing or gas in either bay. The 1962 house tests positive for lead in the door casing paint, so the demolition is done by a certified renovator under containment.

Bearing check: in the attic, ceiling joists run perpendicular to the hall wall and lap over it. It bears. No point load in sight, single story, so the code tables apply.

Header: roof and ceiling only, building width 28 feet, the jurisdiction's ground snow load, span about 38 inches. The table in this jurisdiction's adopted edition returns a doubled header of a given depth and one jack stud each end. The application lists exactly that.

Shoring: the joists lap over the wall and bear from both sides, so two temporary walls go up: 30 inches back on the hall side, 24 inches back on the bathroom side against the vanity.

Below: the crawlspace shows the wall over a girder. The new jacks land on the plate over the girder, so no blocking is needed. Had the latch-side jack landed in a joist bay off the girder line, it would have needed blocking first.

Switch: the old box sat 4 inches inside the new opening. The cable had 9 inches of slack, enough to reach a new box in the next bay on the latch side; it is set at 40 inches at the therapist's direction.

Patch: the inspector saw the header and jacks open; drywall and casing went on the next day. The door hung, the new clear width measured 32.5 inches, and the 5 inches gained over the hinge-and-stop approach (32.5 minus 27.5) is what the wall was opened for.

How to verify the work

Record the clear width on the job, measured the same way as before. Pencil-mark the drywall joint over the header and check it on a follow-up a week later for a crack line, and ask whether doors in the room above still latch as they did. A header that is moving shows up there first.

References

• IRC Section R602.7 (headers) and Table R602.3(1) (fastening), as adopted by your jurisdiction; check the edition for table numbering.
• NEC Articles 300, 314 and 334, and Section 210.12, as adopted by your jurisdiction.
• EPA Renovation, Repair and Painting Rule, 40 CFR 745 Subpart E; OSHA respiratory protection, 29 CFR 1910.134.
• 2010 ADA Standards for Accessible Design, 404.2.3 (clear width), used as a dimensional reference only in a private home.
• See related: How to Measure Clear Width and Gain It Without Widening; Reach Ranges and Control Heights; What the ADA Does and Does Not Cover in a Private Home.