Every piled building raises the same question: where do the two-pile and four-pile caps come from, and does anyone still have the CAD pile layout from the last project? Redrawing caps for each job wastes time, and counting piles by hand on a plan is easy to get wrong.
A pile family in Revit solves both problems with two nested families: a pile family whose size and length are parameters, placed inside a cap family whose pile spacing is a parameter. Build it once, change a few numbers to get a new cap, and let the schedule count the piles. This article walks through 15 steps in Revit 2027, from the template to the pile count. For a structured course on building component libraries, the Institute runs a Revit family creation course.
What a pile family in Revit is made of
A pile foundation in the model has three parts: the pile shaft, the pile cap around the pile heads, and the length of pile embedded in the cap concrete. In Revit both the pile and the cap belong to the Structural Foundations category, but they should be two separate families: the cap contains the pile, which makes it a nested family.
The Institute's sample model uses the two-pile cap M_Pile Cap-2 Pile, type 800x1450, with these parameters: a 700 mm thick cap, 150 mm pile embedment, and 300 mm from pile centre to cap edge. This article rebuilds the same arrangement as your own family. The minimum pile spacing comes from the pile design standard your office applies; the example uses 850 mm to match the 1450 mm cap width.
The key setting is the Shared box on the pile family. With it, the project schedule sees every pile inside every cap; without it, the schedule sees caps only.
Before you build the pile cap family
You need Revit 2027 and the Metric Structural Foundation.rft template in the English folder of the family templates. You also need a structural project with a foundation plan to load into. Save both .rfa files in your office library folder, not in the project folder.
The general idea of parametric families is covered in how to create a family in Revit. This article belongs to the Institute's Revit Structure series.
Revit pile foundation, part one: the square pile
Step 1 — Open the Metric Structural Foundation template
Go to File › New › Family. The New Family - Select Template File dialog opens.
Set Look in to the English folder, pick Metric Structural Foundation.rft and click Open. The family editor opens on the Ref. Level plan with two reference planes crossing at the centre.
Step 2 — Set the model material to Precast Concrete
Click an empty spot so the Properties palette shows the family settings. The type selector reads Family: Structural Foundations.
Material for Model Behavior defaults to Other. Driven piles are precast, so choose Precast Concrete and click Apply.
Step 3 — Build the reference planes and the pile size parameter
On the Create tab click Reference Plane and draw two vertical and two horizontal planes around the centre. Type DI, place a dimension string through three planes in each direction and click its EQ symbol. Add an overall dimension in each direction.
Select an overall dimension and click Create Parameter on the Label Dimension panel.
Parameter Properties defaults to Type, which is what we want: each pile size is a type. Name it Cạnh cọc, the pile size, and click OK. Give the other overall dimension the same label in the Label box so the section stays square.
Step 4 — Model the shaft with Extrusion
Click Create › Extrusion, pick the rectangle tool on the Draw panel and drag from one plane intersection to the opposite one. Four padlocks appear next to the sketch edges; click each one closed.
In Properties set Extrusion End to -12000 so the shaft runs below Ref. Level, then click the green tick on the Mode panel. The family origin sits at the pile head, the point users snap to when placing a pile.
Step 5 — Lock the pile length in the Front elevation
Open Elevations › Front. Draw a horizontal reference plane just below the pile tip, dimension from the Ref. Level line to it, click Create Parameter, name it Chiều dài cọc, the pile length, and choose Instance. Piles of the same size vary in length with the ground, so length is an instance parameter.
Type AL, click the new plane, then the bottom edge of the pile, and close the padlock. From now on the tip follows the length.
Step 6 — Map the material to Structural Material
Select the pile solid. The Material row in Properties has a small button at its right edge; click it to open Associate Family Parameter.
Choose Structural Material and click OK. The material now follows the family's structural parameter, so a Material Takeoff in the project reads the right concrete grade.
Step 7 — Create two pile types and flex them
On the Create tab, Properties panel, click Family Types. Click New Type, name it 250x250, and enter 250 for the pile size and 12000 for the pile length. Click the Structural Material cell; its browse button opens the Material Browser, where you pick a concrete material.
Add a 300x300 type with a size of 300 and click Apply. The pile behind the dialog changes section at once. Instance parameters show default after the name.
Step 8 — Turn on Shared and save the pile
Click an empty spot, tick Shared in the Other group of Properties and click Apply.
Save the file as Cọc vuông BTCT.rfa. The family name is what the schedule prints, so make it readable.
Pile cap family in Revit: nesting the piles
Step 9 — Frame the cap and write the width formula
Start a new family from the same template and set Material for Model Behavior to Concrete. Draw reference planes for both cap edges and both pile centres. Dimension them, set each string to EQ, apply the template's Width and Length labels, and create a type parameter Khoảng cách tim cọc, the pile spacing, on the dimension between pile centres.
Model the cap with an Extrusion locked to the four edges, Extrusion End -700, then lock its bottom face in the Front view to the Foundation Thickness label. Open Family Types and add a parameter Khoảng hở mép, the edge clearance.
In the Formula column of Width type Khoảng cách tim cọc + 2 * Khoảng hở mép. Width becomes 1450 and turns grey because it can no longer be typed. Change the spacing and the cap grows with it.
Step 10 — Load the pile into the cap
Save the cap as Đài 2 cọc.rfa. Switch back to the pile family and click Load into Project on the Family Editor panel.
The Load into Projects dialog lists every open project and family. Tick only Đài 2 cọc.rfa and click OK.
Step 11 — Place two piles and lock their centres
Revit switches to the cap with Modify | Place Component running for the 250x250 pile. Before clicking, set Height Offset From Level to -550: the cap is 700 thick and the pile is embedded 150, so the pile head sits at -550.
Place two piles on the two pile-centre intersections. Properties shows Elevation at Top -550 and Elevation at Bottom -12550. Type AL, click a pile-centre plane, then the pile's centre line; Revit reports Center (Left/Right). Close the padlock, then repeat for the second pile.
Step 12 — Add a pile type parameter for both piles
In Family Types click New Parameter, name it Loại cọc, the pile type, and set Data Type to the last entry, <Family Type...>. The Select Category dialog appears; choose Structural Foundations.
Select both piles with Ctrl, scroll Properties down to Other and set Label to Loại cọc. The button at the right edge of the Chiều dài cọc row links the pile length to a new instance parameter of the cap with the same name.
Step 13 — Flex the cap in Family Types
Open the cap's Family Types, change three values and click Apply.
The piles move apart, grow in section and shorten while staying centred in the cap. Set 250x250, 850 and 12000 back and save.
Count piles in Revit with a schedule
Step 14 — Load the cap into the project and place it
Open the project's foundation plan first. In the cap family click Load into Project, ticking only the project this time. If the placement opens in another floor plan, press Esc, go back to the foundation plan and use Structure › Foundation › Isolated.
The contextual tab reads Modify | Place Isolated Foundation. Click to place the cap; each cap has its own Chiều dài cọc value, so piles under each column follow the ground without extra types.
Step 15 — Count the piles with a schedule
Go to View › Schedules › Schedule/Quantities, type Structural Foundations in the category search box and name the schedule. On Fields add Family and Type and Count. On Sorting/Grouping sort by Family and Type, tick Grand totals and clear Itemize every instance.
The sample model returns Cọc vuông BTCT: 250x250 with 2 piles and Đài 2 cọc: 800x1450 with 1 cap. The model's existing piles, type Po- Pile Square : D350, count 24, which matches 4 two-pile caps plus 4 four-pile caps.
The schedule counts by type name, so check type names against the drawing notes: sheet KC-01.2 notes 250 mm square driven piles while the pile type in the model is D350. Carry on with pile and cap concrete volumes in concrete quantities in Revit, and with cap reinforcement in column and foundation reinforcement.
Growing your Revit pile library
- Four-pile cap: add a pair of pile-centre planes in the Length direction, use the same formula for Length, place four piles and give them the same pile type label.
- Pile tip: model it with a Blend under the shaft with a negative depth; check it in 3D, because the wrong sign turns the tip upward.
- Bored piles: swap the square Extrusion for a circle with a diameter parameter; the nesting stays the same.
This nested family Revit workflow is described by Autodesk in Create a Family with Nested and Shared Components.
When the pile family does not work
| Symptom | Cause | Fix |
|---|---|---|
| The schedule lists caps but no piles | The pile family was not Shared before loading into the cap | Tick Shared, reload the pile into the cap, reload the cap into the project |
| The shaft grows upward from Ref. Level | Extrusion End is positive | Enter a negative Extrusion End, then lock the bottom to the tip plane |
| Changing pile size does not change the pile | Sketch padlocks left open | Edit the Extrusion and close all four padlocks |
| Changing spacing moves piles off their centres | Pile centres not aligned and locked | Align again, pick Center Left/Right of the pile, lock |
| Width cannot be typed | Width is driven by a formula | Change the two parameters in the formula |
| The Label list has no pile type | The parameter has the wrong Data Type | Recreate it as Family Type, category Structural Foundations |
| After loading, placement opens on an upper floor | Revit opened another plan of the project | Press Esc, open the foundation plan, use Structure › Isolated |
Five common misconceptions
| What people say | What Revit 2027 actually does |
|---|---|
| The cap has to draw the pile geometry itself | The cap holds a separate pile family, swapped by the pile type parameter |
| A nested family is always counted in schedules | Only when the pile family is Shared |
| The pile length parameter can go into a schedule | A family parameter states it cannot appear in schedules or tags; that needs a shared parameter |
| Each pile length needs its own type | Length is an instance parameter, edited on each cap |
| A downloaded pile family is good enough | Downloaded files rarely match your office's detailing, type names and materials |
In short, a pile family in Revit is worth building once for the whole office: parametric piles, a cap driven by a formula, and the Shared box so every pile count comes straight from the model.
Frequently asked questions
How do I count piles in Revit?
Create a Schedule/Quantities for Structural Foundations with Family and Type and Count, and clear Itemize every instance. Piles inside caps only appear when the pile family is Shared.
Where should the pile family origin be?
At the pile head, on Ref. Level. When the length changes only the tip moves, and the placement point stays put.
How do I change the pile size for every cap at once?
Open Type Properties of the cap type and change the pile type parameter. Every cap of that type follows.
Can this family become a three-pile or six-pile cap?
Yes: add pile-centre planes and piles, then lock them as in step 11. Keep each pile arrangement as its own cap family.