Headers

Four openings, four headers

In Doors and windows the example house got door P1 and windows J1, J2 and J3. Each one was created with the default header of a stick-built project in the Brazil market: a box of two Ue 200 x 40 x 12 x 1.25, resting on one jack stud on each side.

In most projects that default holds. When it does not, or when the supplier works with a different assembly, the Header tool changes the header of one opening without touching the rest of the frame.

The header is not a piece you draw. It comes from the opening, and the tool only changes the choices the opening stores. That is why each change is always one Ctrl+Z step, and Back to default restores the project header.

In the example house: P1 will become an I header with two jack studs, and a project rule will put an I header on every opening from 1.00 m up, which means the three windows.

The beam that carries the wall above to the sides

The studs that fell inside the opening were cut. Their load (roof, wall above, floor) reaches the header through the cripple studs, and the header delivers it to the sides. The header section decides how much it can carry; the support decides where it delivers.

A beam, with the deflection of something that holds up a wall

NBR 16970-2, the Brazilian standard for light steel framing design, defines the header and sets its deflection limit. The resistance of the section, as for any cold-formed section, comes from NBR 14762, the Brazilian cold-formed steel standard. The CalcSteel engine applies both.

What the standard does not say

The standard does not choose the header type, the section or how many jack studs it gets. That is a design and supplier decision. The app starts with the default of the project market and checks whatever you choose.

Start from the default and change what the engine asks for

• 2 × Ue 200: 1.25 mm box, the stick-built default
• 1 jack stud: per side of the opening, to start
• L/500: maximum deflection, 2.4 mm over a 1.20 m opening
• 200 mm: the depth the header takes above the opening

1. Calculate before changing. The default holds for most openings of a single-story house. Calculate the project and change only the header that fails. Changing all of them "to be safe" bulks up the material list for no gain.
2. Failed at the support? One more jack stud. If the engine flags web crippling, the header section is fine and the bearing is short. Two jack studs per side double the bearing area. Only then think about a thicker section.
3. Failed on deflection or bending? Thickness, then depth. Going from 1.25 to 1.55 mm keeps the 200 mm depth and leaves the opening alone. A deeper section eats space above the opening; check that it still fits under the top track.
4. Check the total height. Sill + opening + header depth must stay below the top track. In a 2.80 m wall: door, 0 + 2100 + 200 = 2300; window, 1000 + 1000 + 200 = 2200. There is room left for the cripple studs.
5. Use the project rule for what repeats. If every window in the project needs the same header, one rule by minimum width solves it at once and applies to new openings too. Leave the per-opening choice for the exception.
6. Clip only with the angle designed separately. Clip support saves jack studs. The angle and the screws of the clip are designed separately, with the supplier: use it when the supplier has the part tested for the load.

1. Open the view and arm the tool

Select the front wall and click Open view on its card, in the footer. On the LSF card, click the Header button. The Header box opens next to the card. The tool works in the wall view and in 3D; in the view the header is bigger and easier to find.

2. Hover over the header

The header under the cursor lights up and a label says which opening it belongs to and which section it has. Click.

3. Change the type

In Type, click I. The header is rebuilt right away, with two Ue back to back, and the label next to the field changes from "project default" to "this opening". The Back to default link appears at the top of the box.

4. Two jack studs per side

In Jack studs, click 2. One more jack stud appears on each side, next to the first. If there is no room in the wall for the extra jack studs, the box refuses and says why.

5. Clip support

In Support, click Clip. The jack studs go away, the header extends to the king studs and is now fixed with an angle. The Jack studs field is greyed out: "no jack stud with a clip". In the example, we go back to Jack right after.

The footer follows along

The opening footer, at the bottom of the screen, sums up the header in one line after each change. It is the fastest way to check an opening without opening the box.

6. Change the section

Back on Jack support, click the Section field. The header catalog opens, with C family sections only: in a stick-built project, Ue of 90, 140 and 200 mm, from 0.8 to 2 mm, with the weight per meter. Choose Ue 200x40x12x1.55. The label changes to "this opening" and the depth stays at 200 mm, the web of the section.

7. Go back to the default and write the rule

Click Back to default: P1 goes back to a box, Ue 200 x 1.25, one jack stud. It is a single Ctrl+Z step.

Now, the project. In the Project rule block, enter Opening ≥ 1000 mm and click I. Before applying, the box already counts how many openings the rule reaches: 3, the 1200 mm windows. The 800 mm door is left out.

Click Apply rule. The block gets the active tag and the button becomes Update rule.

8. Check it on a window

Click the header of J1. Type and section show the project rule label: its header is an I, and it came from the rule, not from a choice on the opening.

9. Exit and check in 3D

Esc closes the box and disarms the tool. In 3D, the front wall shows P1 with the box and J1 with the I header. The rule travels with the project: it opens the same on another computer and applies to every new opening from 1.00 m up.

The order of precedence

Each header field (type, section, jack studs, support) is decided separately, in this order. The label next to the field says where it came from.

The Header box

The header of the opening

The project rule

Sections · from the project settings

Below the rule, the box shows the default section of the Header and of the Head track (U 92x38x0.95 in a stick-built project), with the Change in the project settings link. Changing it there changes every header that follows the default.

Outside the box

In the opening footer, the Header field sums it all up in one line, with "· project rule" when it came from the rule, and the Edit header › link opens the box with the opening already selected.

The box refusals, and what to do

The box only refuses a change that leaves the header worse than it was. The text appears in red below the field, and the header does not change.

1. "The header with this depth goes past the top track." The deeper section does not fit between the opening and the top of the wall; the box says how many millimeters are missing. Fix: more thickness with the same depth, or a lower opening.
2. "The header with this depth runs into the truss that passes over the opening." There is a truss bearing on the wall just above. Fix: a shallower section, or a lattice header that goes up to the chord.
3. "With these jack studs the opening no longer fits in the wall." The extra jack studs run into the joint or the neighboring opening. Fix: slide the opening using the clearances, or keep fewer jack studs and check in the engine.
4. "The header is a Ue section (C family)." A U track, a hat section or a strap do not work as a beam over the opening. The box catalog already filters them out; the refusal appears if the section comes from somewhere else.
5. "This opening has a lattice header." Section and make-up belong to a solid header. Fix: change the type to Box, I or Single first.
6. "No opening in the project has this width." It is not an error: the rule is saved and applies to the next ones. Check the number if you expected it to reach some.
7. Load over the opening, away from the support. When a column or a truss bears on the opening more than 2 cm from the support, the box warns: "It lands over the opening, away from the support... The header takes this load: the stud below does not." It is the header that will bend under the point load. Calculate and check.
8. Assuming a clip is checked. With a clip there is no jack stud, so there is no web crippling check, and the angle and its screws are designed separately. A header that passes with a clip does not mean the clip passes.

A simply supported beam, with three checks

Model. The header is a member of the model, pinned at both ends, like the head track, the sill and the cripple studs. The load comes in through the cripple studs and whatever else bears on the opening, and goes out through the jack studs (or the king stud, with a clip).

Section. The type becomes the section of the member: box and I are two Ue working together, Single is one. The section and the thickness come in with the catalog properties.

Checks.

The path, in one line

Wall view → LSF card → Header → click the header → Type, Section, Jack studs, Support → (or) Project rule: minimum width, type, Apply rule → Esc → calculate and read the VG.

The example so far

• 4: headers, P1 box and J1 to J3 as I
• 1: project rule, opening ≥ 1000, type I
• 2 × Ue 200: 1.25 mm section in all four
• 1: jack stud per side in each opening