Copper pours

A copper pour covers the surface area of a board with copper while maintaining a certain buffer from other copper features, such as routes and pads. A ‘bridge’ can connect between a copper feature and a pour.

Defining pours

Pours are defined in their own section in the board’s JSON under shapes

  "shapes": {
        "layers": [
        "type": "layer"

The above will place a pour over the entire top and bottom layer of the board. It’s possible to pour a specific shape, and that’s done just like any other shape definition.


Since PCBmodE does not have a netlist, those bridges need to be added manually, and careful attention needs to be paid to prevent shorts – there’s no DRC!


Even if you’re pouring over a single layer, the layers definition only accepts a list, so you’d use ["bottom"], not "bottom".

Defining buffers

The global settings for the buffer size between the pour and a feature is defined in the board’s JSON file, as follows:

"distances": {
  "from-pour-to": {
    "drill": 0.4,
    "outline": 0.25,
    "pad": 0.4,
    "route": 0.25

If this block, or any of its definitions, is missing, defaults will be used.

These global settings can be overridden for every shape and route. For routes, it’s done using the pcbmode:buffer-to-pour definition, as described in Routing. For shapes it’s done using the buffer-to-pour definition, as described in Shapes.