Hatch missing in the PDF: why, and how to fix it
Walls that look filled on screen come out as empty boxes. The cause is usually one of five things — in order.
A classic thing to notice minutes before issuing a sheet: concrete, insulation and floor hatches are all there on screen, and in the PDF the walls are empty boxes. It is one of the longest-running threads on the Autodesk forums. The cause is nearly always one of the following.
1. The hatch scale is too large
A hatch pattern repeats at an interval. If the scale is too large, the gap between two pattern lines is wider than the region being hatched and no line lands inside it — the hatch technically exists and visibly does not. ISO patterns are designed for millimetre drawings; on an imperial drawing the scale needs dividing by roughly 25.4.
2. The layer is off or frozen
Hatch usually lives on its own layer. If that layer is off you may not notice on screen, but it is certainly absent from the print. Frozen layers do not plot either. And there is the plot flag: a layer that is visible but marked not-to-print stays on screen and vanishes in the PDF — the sneakiest of the three.
3. Draw order
A solid hatch covers whatever it lands on; equally, a hatch can end up buried under another fill. Sending hatches to the back and linework to the front with DRAWORDER settles it.
4. Display and plot quality settings
Some print settings simplify or skip hatches outright. Check that any “show hatches” or “solid fill” option is on when you export.
5. The converter ignores patterns
If you are converting with something other than AutoCAD, this is the most common cause. Many online converters draw only the boundary of a HATCH entity and never generate the pattern, leaving an empty box. It is easy to confirm: if the wall has edges in the PDF but nothing inside, the pattern was never produced.
Quick checklist
- Is the hatch layer on, not frozen, and set to plot?
- Does the hatch scale suit the drawing unit — millimetres or inches?
- Did a solid hatch end up under another object?
- At 400% zoom in the PDF, are the pattern lines there?
- Does the same file hatch correctly through a different tool?
Try it with your own drawing
Drop a DWG or DXF and take away a true-scale vector PDF. Nothing to install.
Related reading
How to convert a DWG file to PDF properly
Turning a drawing into a PDF is easy. Doing it without losing the scale, the colours and the hatches is not. Step by step.
Opening a DWG file without AutoCAD
You have no licence but you need to read the drawing. The options, what each is good for, and where each falls short.
DWG vs DXF: what differs and which one to send
Both are drawing files, but they are not the same thing. One is binary, the other readable text — and that difference sometimes saves a project.