Column reinforcement in Revit is three groups of bars, not one. The vertical bars carry axial load and bending and run the full height of the column. The ties stop those bars from buckling outwards and take the shear. The starter bars rise out of the storey below so the column above has something to lap onto.
Those three groups raise the three questions people ask most: where do the ties tighten up, at what level are the bars lapped, and how deep do the column bars reach into the footing. This article answers the detailing first, then shows where Revit records that detailing as a parameter.
The fifteen steps below were captured on Revit 2027.2 with the English interface, working on a four-storey model that already carries reinforcement. If the columns are not modelled yet, read structural columns in Revit first; for the whole documentation workflow, see the Revit Structure course.
Column rebar detailing rules to settle before opening Revit
Ties are not spaced evenly over the full height. At both ends of the column, where it meets the beams and the slab, moment and shear are largest, so the ties must tighten up. Over the middle of the column they can open out again. That tightened length is the joint region.
The sample model does exactly that. The tags read 17 Ø6 a100 for the close tie zone of the column, 7 Ø6 a200 for the wide zone, 5 Ø6 a100 for the length inside the joint and 12 Ø6 a100 for the beam stirrups. The column is C1.1 at 220×300 and the beam DX2.1 at 220×400.
For lap positions the rule is one sentence long: lap where the forces are small, stay out of the joint, and stagger the bars instead of lapping them all at one section. The actual figures — which level, how many bar diameters of overlap — belong to the design and to the standard in force, and there is no single number good for every project. Revit does not invent that figure; it keeps the drawing and the schedule tied to the one you choose.
Rebar cover follows TCVN 5574:2018
TCVN 5574:2018, clause 10.3.1.2 and Table 19, gives the minimum by service condition, not by element name. The table reads 20 mm inside a covered space at normal humidity, 25 mm at raised humidity, 30 mm outdoors and 40 mm in soil. Three adjustments follow: precast elements take 5 mm less, secondary bars take 5 mm less, and the cover is never smaller than the bar diameter.
A column indoors and a basement column in contact with soil therefore do not share a value. It is also why an isolated foundation and a strip foundation always carry thicker cover than a column.
Preparing the file and the views for column reinforcement
A column differs from a slab because it stands up. Checking its reinforcement needs two kinds of view working together: an elevation section running the full height, to show the laps and the close tie zones, and a cross section at every point where the detailing changes.
The cross section in the sample model reads straight onto the site drawing: 220 × 300, tags 1 and 4 both reading 3x Ø16, tag 2 reading Ø6. Six vertical bars in all. The three settings to fix before any of this are covered in rebar settings in Revit.
This article is part of the Institute's Revit Structure series.
Column reinforcement in Revit: vertical bars and ties
Step 1 — Open the elevation section of the column
Reinforcement only appears in a view that cuts its host. Open the elevation section first, because it is the only view that shows the full height of the column.
Step 2 — Read back the cover on the column
Select the column and scroll Properties down to the Structural group.
| Parameter | Value read on the model |
|---|---|
| Column type | P=Cot KC 220x400, Structural Columns |
| Rebar Cover - Bottom Face and Other Faces | Rebar Cover 1 <25 mm> |
| System Length and Volume | 3900.0 mm and 0.322 m³ |
| Mark and Column Location Mark | C2.2 and B-2 |
This column is set with Base Level 2F at Base Offset −350.0 and Top Level 3F at Top Offset −50.0. That pair of constraints decides how long the vertical bars become when you choose Expand to Host.
Step 3 — Select the column as the host
Click the column in plan or in section. Properties must change to Structural Columns (1). If nothing selects, see the troubleshooting table below.
Step 4 — Launch Rebar from the Concrete tab
With the column still selected, go to the Concrete tab and click Rebar. The ribbon switches to the contextual tab Modify | Place Rebar.
The four middle panels decide where the bar lands and which way it faces: Family, Placement Methods, Placement Plane and Placement Orientation.
Step 5 — Place the vertical bars with Expand to Host
Pick the straight bar shape in the Shape Browser, choose Expand to Host on Placement Methods, then Parallel to Cover on Placement Orientation. The bar stretches over the full height of the column.
| Parameter | Value read on the model |
|---|---|
| Type and shape | Rebar Bar Ø16, Shape M_00, a straight bar |
| Style | Standard, a plain bar rather than a tie |
| Start of Bar, End of Bar | both None, no hooks |
| Partition | CỘT C1, the partition that groups bars in the schedule |
Step 6 — Use Fixed Number as the layout rule
Vertical bars differ from ties: the count is a design decision, not a consequence of a spacing. Their layout rule is therefore Fixed Number with Quantity typed in, and the Spacing cell left empty. The set in the image is Fixed Number with Quantity 3, one row of three Ø16 bars.
Step 7 — Pick the tie shape and the Stirrup / Tie style
Ties are a different matter. Pick the closed tie shape in the Shape Browser, choose Perpendicular to Cover on Placement Orientation, then place the bar on the cross section of the column.
| Parameter | Value read on the model |
|---|---|
| Style | Stirrup / Tie, quite unlike the Standard of a vertical bar |
| Stirrup/Tie Attachment | Interior Face of Cover, the tie hugs the inner cover face |
| Shape | BS_M_T1, a closed rectangular tie |
Stirrup/Tie Attachment is the parameter people skip. It decides whether the tie wraps the inner or the outer cover face, which is the same as deciding the real size of the tie.
Step 8 — Declare the 135 degree seismic hooks
Both Hook At Start and Hook At End on the tie set in the sample model read Stirrup Seismic - 135, the seismic tie hook bent through 135 degrees, with both ends set to Hook.
A hook is a named object, not a number you type. Choose the right hook type and the schedule adds the hook length to the bar length correctly.
Tie spacing at the joint and starter bars between storeys
Step 9 — Split the column height into tie zones
A column is not one tie set but several in sequence. The tidiest way is to place them one zone at a time, each zone its own set.
Column lift C2.1 between level 2F at +3.90 and level 3F at +7.50 is 3600 high and carries four tie zones. From the bottom: 17 Ø6 a100 over 1600, 5 Ø6 a100 over two 400 lengths inside the joint, 6 Ø6 a200 over 1200 in the middle, then 17 Ø6 a100 over the top 1600.
Step 10 — Set the spacing with Maximum Spacing
For ties, Maximum Spacing is the right rule: the engineer states a spacing that must not be exceeded and Revit fits as many ties as the real length needs. The set in the image uses a spacing of 100.0 mm, and Revit computes Quantity 17. Change the storey height and the tie count follows on its own.
Typing a count into Quantity, on the other hand, does nothing, because that cell is greyed out while the layout rule is Maximum Spacing.
Step 11 — Place the starter bars and choose the lap position
Starter bars are the vertical bars of the storey below carried up through the slab so the column above can lap onto them. In Revit they are simply another set of vertical bars hosted by the lower column, placed with By Two Points and stretched up to the lap level.
A three-dimensional view is the only place where the whole chain of laps is visible at once. The image shows a column running from footing M2 up through C1.2, C2.2 and C3.2, all three at 220×400. One glance tells you which bar has been cut short at the beam face.
Step 12 — Lap bars with Splice or Insert Coupler
Select a bar and the ribbon shows the contextual tab Modify | Structural Rebar.
The Splice panel holds two buttons: Splice laps two bars, Insert Coupler drops in a mechanical coupler. The Host panel holds Propagate Rebar, which copies a finished set onto identical columns — the single biggest time saver in a multi-storey building.
That image was captured in a three-dimensional view, and there the tab has no Presentation panel while Propagate Rebar, Remove Bar, Splice and Bending Detail are all greyed out. Open a plan or a section and the panels and buttons come back.
Isolated foundation and strip foundation reinforcement in Revit
Step 13 — Model the footing, then place the bottom mat
Footings do not live on the Concrete tab but on the Structure tab, in the Foundation panel, with three buttons: Isolated, Wall and Slab.
Autodesk's own tooltips divide the work clearly.
| Button | What the tooltip says it does |
|---|---|
| Isolated | Adds footings or pile caps; they attach automatically to the bottom of columns |
| Wall | Creates foundations hosted by walls, constrained to the wall they support |
| Slab | Adds a foundation slab, which needs no supporting element |
A pad footing or a pile cap uses Isolated, and the Isolated Foundations page from Autodesk lists the multi-pile cap types too. A strip footing under a bearing wall uses Wall, while a strip under a row of columns is modelled as a ground beam and reinforced like a beam, following beam reinforcement in Revit.
Step 14 — Check the starter bars in the cap in three dimensions
The bottom mat of the cap is the main load-carrying layer, while the column starter bars have to anchor deep enough into it. A three-dimensional view shows both at once.
Footing M1 in the sample model is a two-pile cap. The cap cage and the starter bars of column C1.1 appear together, so the anchorage depth and any clash between the two cages can be judged on the spot.
Step 15 — Read the column rebar schedule
The schedule in the sample model groups by partition: group CỘT C1 totals 119 bars, 361.20 metres and 322.53 kilograms, while group CỘT C2 totals 120 bars, 866.24 metres and 812.97 kilograms. Its columns are the bar mark, the diameter, the shape, the length of one bar, the count per element, the number of elements, the total length and the total weight. Building that schedule is covered in rebar schedules in Revit.
When it does not work
| Symptom | Cause and fix |
|---|---|
| Clicking the column never selects it | The Select Elements by Face toggle at the right of the status bar is off. Switch it on |
| All seven Reinforcement buttons are greyed out | You are on a sheet. Open a plan or a section |
| Propagate Rebar and Splice are greyed out | You are in a three-dimensional view. Open a plan or a section and select the bar again |
| Typing a tie count into Quantity does nothing | The layout rule is Maximum Spacing, so Quantity is greyed. Change the spacing, or switch to Fixed Number |
| Bars are placed but the section stays empty | The section does not cut the column, or View Unobscured is not ticked for that view |
| The tie comes out larger or smaller than expected | Check Stirrup/Tie Attachment: the inner and the outer cover face give two different sizes |
What people often get wrong
| Common belief | What is actually true |
|---|---|
| Column ties are spaced evenly over the full height | Both ends must be tighter. The sample model reads a100 at the ends and a200 in the middle |
| Column bars may be lapped anywhere as long as the lap is long enough | The lap must avoid the joint and the bars must be staggered, following the design |
| Vertical bars and ties are declared the same way in Revit | They differ in Style: vertical bars are Standard, ties are Stirrup / Tie |
| One command models every kind of footing | The Structure tab has three: Isolated for pads and pile caps, Wall for footings under walls, Slab for foundation slabs |
Frequently asked questions
How many vertical bars does a 220x300 column need?
The count comes from the analysis; there is no universal answer. Column C1.1 in the sample model of this article uses six Ø16 bars, in two rows of three along the 300 side.
What tie spacing should the joint region use?
The figure has to come from the design and the standard in force. The sample model uses a100 over both end zones and a200 in the middle, with Ø6 ties.
How are starter bars modelled in Revit?
As an ordinary set of vertical bars hosted by the column below, placed with By Two Points and stretched up to the lap level.
Why can the Quantity cell of a tie set not be edited?
Because the layout rule is Maximum Spacing, so Revit derives the count from the spacing. Switch to Fixed Number to type the count.
Which button models a strip footing?
A strip under a bearing wall uses the Wall button in the Foundation panel. A strip under a row of columns is modelled as a ground beam and reinforced like a beam.
Related articles
- Rebar settings in Revit — bar diameters, cover and bend radius
- Beam reinforcement in Revit — main bars, stirrups and anchorage
- Slab reinforcement in Revit — two layers, top bars and trimmers
- Rebar schedules in Revit — bar schedules, lengths and weights
- Structural columns in Revit — modelling the column before reinforcing it