Worldbuilding
Modular Grid & Kit Dimension Planner
Direct answer
A modular kit stays interchangeable when every panel dimension is an integer multiple of one base grid. A 4 m wall panel on a 10 cm grid contains 40 grid units. Across a 24 m target span it repeats exactly six times, with no fractional panel, unsnapped seam or accumulated remainder.
Result
- Kit alignment
- —
- Module dimensions in grid units
- —
- Whole modules across target
- —
- Whole module rows
- —
- Nearest exact horizontal span
- —m
- Nearest exact vertical span
- —m
- Unfilled horizontal remainder
- —m
- Unfilled vertical remainder
- —m
Method & assumptions
How this is worked out
Each module dimension is divided by the base grid. A dimension is grid-safe when the result is an integer within floating-point tolerance.
Whole panel counts use the target span divided by module size. Remainder shows what cannot be covered without a trim piece. The nearest exact span rounds to the closest whole module count.
Keep pivots, collision thickness, openings and decorative variants on the same base grid. A kit can use larger design modules while still snapping to a smaller common denominator.
Practical base-grid choices
| Base grid | Useful for | Watch for |
|---|---|---|
| 1 cm | Precision props and trim | Too fine for primary blockout |
| 5 cm | Detailed interiors | More snap positions to manage |
| 10 cm | General architecture | Good default for metric kits |
| 25 cm | Large industrial modules | Small openings may need sub-grid pieces |
| 50 cm | Fast greybox and macro kits | Too coarse for finish pieces |
A project may use nested grids. The important rule is that larger increments remain exact multiples of the smallest supported grid.
Questions
What grid size should a modular kit use?
Ten centimetres is a practical metric default for architectural kits. Use five centimetres for detailed interiors or 25 to 50 centimetres for large blockout pieces, while keeping every larger increment divisible by the smallest one.
Why do seams drift after many repeated pieces?
One or more dimensions are not exact multiples of the grid, or an export/import scale introduced decimals. Small errors accumulate with every repetition. Check dimensions, pivots and engine units before creating more variants.
Should doors and windows follow the module width?
Their outer frames should land on the base grid, but they do not need to occupy a full wall module. Build openings and fillers from the same common denominator so combinations still close without bespoke gaps.