What is Grungit?
Grungit is an addon that automatically and effortlessly adds wear and tear to your models with a single click. The result is fully controllable and can deliver anything from imperfections and light wear to heavy damage.

Why Grungit?
Unlike other methods, Grungit has very little impact on performance and it’s fully compatible with EEVEE, but surely the most important benefit is the considerable amount of precious time it saves.

The main goal of Grungit is to assist you, not to dictate a specific style that might not suit your needs, and it doesn’t impact your workflow. That makes it very versatile and can deliver all kinds of results : You can use it to add subtle surface imperfections to give your renders an additional layer of realism, or you can make a painted surface for a machine with a lot of grunge, scratches and dirt.

What are the benefits of Grungit?
High quality edge wear, grunge, and dirt with a single click of a button

Compatible with EEVEE

Simple And Fast

1-Click PBR baking

Fully Customizable

Full PBR

Topology-independent

Keeps existing materials and works with add-ons that use the Principled BSDF node.

advanced mode for more manual control

Manual hand-painting to add or remove grunge and/or dirt

Quick mode (no edge wear, useful to add imperfections and uniform wear)

Supports multiple objects and multiple materials

Animatable and adjustable in real-time

Fast render times

Auto-unwrapping

Limitations:
Unexpected behavior on very thin surfaces when the edge wear scale is too big
Some users reported that Grungit does not work with EEVEE in macOS. Unfortunately this is due to a bad OpenGL driver by Apple and there isn’t much I (or the Blender developers) could do. In order to render with EEVEE, you need to use the PBR baking feature to convert your materials first.
Baking many objects and materials is a bit slower than baking a single object and material
What do people say about Grungit?
Very easy and straightforward. A simple bake and ready to go with a few intuitive slides.

I like how quickly Grungit lets you test readability in hard-surfaces with the procedural wear, letting you tweak the effect to your liking through several kinds of workflows.

It greatly simplifies and reduces my workload when it comes to adding small detail to my models.

The material works really well and I don’t have to make my own materials or import older ones.

It helps me visualize areas of rest vs detail in damaged metal while working on the design. While this would be optimal to do in the finished retopologized mesh, I’ve used Grungit while working with Hi-Poly before baking.

Release notes:
v1.8:

Bug fixes
Grungit now uses a separate UV channel by default
Ignore materials with a name which start with “.”
Add “dirt mask” and “grunge mask” to PBRBake

v1.7:

Bug Fixes
Added an “advanced mode”, “Use Clearcoat”, “Duplicate multi-user materials”, “Ignore unused materials”, and an option to choose between only dirt, only grungit, and dirt+grungit
Remade Grungit node: easier to control, better quality, organized inside, and renders faster in EEVEE
Improved Edge wear
Normal maps are now taken in consideration when generating edge wear.
PBR inputs for the dirt node
Quality improvements
More information on the following link https://blenderartists.org/t/grungit-1-click-wear-and-tear-for-blender/1197208/69

v1.6:

Bug Fixes
Multi-object support
Occlusion is now affected by all objects
UV Pack by material
added 512×512 and 256×256 resolutions
“Quick mode”
Optix baking workaround
1-click PBR Baking

v1.5:

Supporting objects that have multiple materials,
Clearcoat support
Improved edge wear quality, it’s easier to control and works well by default
Quality adjustments
“(Re)create UV maps” now packs faces that share the same material (default behavior)

v1.4:

Iimprovements to the dirt node, mainly a “contrast” parameter
Cracks
Minor bugfixes and quality improvements

v1.3:

Greatly improved dirt layer, it looks a lot better now and it’s easier to control
Quality improvements
Fixed the randomness (in v1.3.1)