Once I have a general idea for the pre-production I move onto the concept breakdowns. Using Photoshop I highlight the unique props (1) separate from the building itself.
Then, bearing in mind I would be using masks on a second UV Set I sectioned the building by areas (2), each area being a combination of modular sections that will be packed into the second 0-1 UV set. My idea for compartmentalizing the building is that I can keep a good resolution.
Once the concept art is planned out I moved into deciding on how best to approach the texture application and modelling. Using a reference I outlined the approach I felt best worked, that being a combination of trim sheets and tiling textures with weighted normals with no need for unique bakes.
--General Breakdown and Material Planning--
With that laid out, I started filtering through references and breaking them down further before outlining the materials and trim sheets necessary.
--Trim Sheet Breakdown--
Going even further into the breakdown I start getting an idea for the trim sheet compositions.
[Pipe & Guttering Trim Sheet]
The pipe and guttering trim will be made similar to my existing pipe trim sheet from another project: https://www.artstation.com/aknightfallows/blog/wLQ4/pipe-trim-sheet-grunge-shader
My general idea for timesheets is to make two versions of each baring maybe the Stone. One version will be the original trim sheet, so for instance the wood will have the paint coating and such, the second trim sheet will be the damaged version, in the case of the wood, it will be the exposed wood. Masks painted on the asset itself will be used to blend between the versions. Dirt, rust and moisture will be blended through their own masks and material function to be controlled separately of the trim sheets.