Revit fill pattern generator: create custom .pat hatch files
Design tile, brick, herringbone, hexagon and crosshatch patterns, check them in a live preview drawn from the file itself, and download a .pat file that imports into Revit and AutoCAD. Then fill your model with our Revit families.
11 presets, tiles to herringboneRevit Model or DraftingMillimetres or inchesPreview drawn from the .patCopy or download the file
File settings
Model patterns are real size and scale with the model (tiles, brick, cladding). Drafting patterns keep the same size on paper at every view scale (cut hatches).
Sizes
All sizes in millimetres.
Tile size without the joint.
Drawn as one line on the joint centre, so lines are spaced at tile + joint. Use 0 for none.
Turns the whole pattern counter-clockwise. 0 for none.
Without the joint. UK brick: 215 × 65 mm.
Drawn as one line on the joint centre (module = brick + joint). UK and EU: 10 mm.
How far each course shifts, as a part of the brick length.
Turns the whole pattern counter-clockwise. 0 for none.
Drawn as one line on the joint centre. Every joint lines up in stack bond.
Turns the whole pattern counter-clockwise. 0 for none.
Length ÷ width must be a simple ratio (6:1, 4:1, 5:2...) or the pattern cannot repeat.
Drawn as one line on the joint centre.
45° gives the classic zigzag; 90° lays the planks along the axes.
Each block is a square of this size, split into planks.
Plank width = block size ÷ planks, from 2 to 8.
Turns the whole pattern counter-clockwise. 0 for none.
Counter-clockwise from horizontal. 45° at 3.175 mm is the ANSI31 hatch.
Perpendicular distance between lines. For Drafting this is the printed spacing.
The second set of lines runs at 90° to the first. 45° gives ANSI37.
Perpendicular distance between lines, the same for both sets.
Point to point, horizontally.
Point to point, vertically. Equal width and height gives a square on edge.
Each edge. The hexagon is 2 × side across the points.
Course heights from the bottom, separated by commas (up to 8).
Stone lengths in a course, separated by commas. Each course shifts the sequence so joints do not line up.
Turns the whole pattern counter-clockwise. 0 for none.
Board width, the same for every row.
Board lengths in one row, separated by commas (up to 8). A row repeats every total length.
Each row shifts by this part of the total row length.
Turns the whole pattern counter-clockwise. 0 for none.
Name
Up to 31 characters: letters, numbers, _ - and $, no spaces or commas (AutoCAD rule). Also the file name.
Shown next to the name in AutoCAD. No commas or semicolons.
Preview
Your .pat file
Load the pattern
Revit
- Go to Manage › Additional Settings › Fill Patterns.
- Under Pattern Type pick Model, the same type as the file, then click New.
- Choose Custom, click Import (Browse) and open the .pat file. Select the pattern and click OK. Leave the import scale at 1: the units are in the file.
AutoCAD
- Save the file in a folder on the support file search path (Options › Files › Support File Search Path). Keep the file name the same as the pattern name.
- Run HATCH and open the Pattern list: custom patterns are listed after the standard ones. In the Hatch and Gradient dialog, set Type to Custom.
Line patterns only: Revit and AutoCAD .pat files cannot hold solid fills or colours. Check a test area in your project before using a pattern on drawings you issue.
Detailing floors and walls in Revit? Get ready-made families for your project.
Browse Revit familiesMake a .pat file in three steps
Pick a pattern and units
Choose millimetres or inches, Model (real size) or Drafting (paper size), and a preset such as square tiles, running bond brick, herringbone or hexagon.
Set the sizes
Type the tile, brick or plank sizes, joint width and rotation. The preview redraws as you type, with one repeat outlined in orange and a scale bar.
Download and import
Download the .pat file or copy its text. In Revit use Manage › Additional Settings › Fill Patterns › New › Custom › Import; in AutoCAD put it on the support path and pick it in HATCH.
How a .pat line family works
A .pat file is plain text. Revit reads a units line at the top and a type line under each pattern header; AutoCAD treats both as comments, so one file works in both programs.
*Tile_300x300, Tiles 300 x 300 mm
;%TYPE=MODEL
0, 0,0, 0,300
90, 0,0, 0,300
Each line after the header is one line family: an endless set of parallel lines.
| Field | Meaning |
|---|---|
| angle | Direction of the lines, in degrees counter-clockwise from horizontal |
| x-origin, y-origin | A point the first line passes through, where its dash sequence starts |
| delta-x | Shift of the next line along the line direction (staggers the dashes) |
| delta-y | Spacing between the lines, measured at right angles to them |
| dash, gap, … | Optional. Positive = pen down, negative = pen up, 0 = dot. Leave out for continuous lines |
Worked example: running bond brick 215 × 65 mm with 10 mm joints is a 225 × 75 mm module. Bed joints are continuous lines every 75 mm. Perpends are vertical lines every 112.5 mm (half a brick) that draw 75 mm, skip 75 mm, and step up one course from one line to the next:
90, 0,0, 75,112.5, 75,-75
The generator writes numbers to 6 decimals and reads its own file back before you download it, so the preview shows what Revit and AutoCAD will draw.
Rules your .pat file must follow
| Rule | Applies to | Source |
|---|---|---|
| Pattern name up to 31 characters: letters, numbers, _ – $, starting with a letter or number | AutoCAD | AutoCAD Customization Guide |
| Each line up to 80 characters | AutoCAD | AutoCAD Customization Guide |
| A blank line after the last pattern, or that pattern is ignored | AutoCAD | AutoCAD Customization Guide |
| A custom pattern file has the same name as its pattern | AutoCAD | Autodesk community advice |
| ;%UNITS=MM or ;%UNITS=INCH at the top, ;%TYPE=MODEL or ;%TYPE=DRAFTING under the header | Revit | Revit Help, file format for fill patterns |
| Line spacing (delta-y) cannot be 0 | Revit | Revit API, FillGrid class |
| Start a dash sequence with a dash and end it with a space, or Revit adds tiny dashes | Revit | Revit API, FillGrid class |
| Very short dashes are stretched to a minimum length | Revit | Revit API, FillGrid class |
Revit also rejects patterns it considers too large or too dense, and Autodesk does not publish the exact limits. Users report problems with repeats over about 20 m (65 ft) and dashes under 1/32″ (0.8 mm); the generator warns you in both cases.
Fill pattern questions
Write the pattern as a .pat file (this generator does it for you), then open Manage › Additional Settings › Fill Patterns. Pick Model or Drafting to match the file, click New, choose Custom, click Import and open the .pat file. Select the pattern, keep the import scale at 1 and click OK.
A model pattern is real size: a 300 mm tile pattern stays 300 mm in the model and scales with the view, so you use it for floors, walls and cladding. A drafting pattern keeps the same printed size at every view scale, which suits cut hatches such as concrete or insulation. The file says which one it is with ;%TYPE=MODEL or ;%TYPE=DRAFTING.
Save the .pat file in a folder on the support file search path (Options › Files) and give the file the same name as the pattern inside it. Then run HATCH: custom patterns appear in the pattern list after the standard ones, or under Type: Custom in the Hatch and Gradient dialog.
Choose Herringbone, enter the plank length and width, and pick the 45° zigzag or the 90° layout. The length divided by the width must be a simple ratio such as 6:1, 4:1 or 5:2; otherwise the plank edges never line up again and the pattern cannot be written as repeating .pat lines. The tool tells you when your sizes do not work.
Revit has internal limits on how big a pattern repeat can be and how close or short its lines are. Autodesk does not publish the numbers; users report trouble with repeats over about 20 m and dashes under 0.8 mm. Use smaller or simpler sizes, a simpler plank ratio, or the Drafting type for fine hatches.
No. A .pat file only describes lines, dashes and dots. In Revit, set the colour and a solid background in the material or the filled region type; in AutoCAD use a solid hatch or a gradient instead.
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