San Diego ADU Guide
Prefab vs. Custom ADUs in San Diego
Both prefab and custom ADUs can work well in San Diego. The right choice depends on your site, budget, and timeline.
Prefab ADUs: pros and cons
Prefab (or modular/panelized) ADUs are built mostly in a factory and assembled on site.
- More predictable timelines and standardized details.
- Less disruption on site once the foundation is ready.
- Limited floor plans and finish options compared to full custom.
Custom ADUs: pros and cons
Custom ADUs are designed specifically for your lot and built on site like a small house.
- Maximum flexibility in layout, rooflines, and finishes.
- Can better respond to tricky lots, slopes, or views.
- More moving parts to coordinate; timelines can be longer.
Which is better for San Diego?
Many San Diego homeowners look at prefab for speed and predictability, then compare it against a couple of custom builders to see how pricing and design flexibility stack up.
Use our builder directory to find both prefab-focused and custom ADU builders serving your neighborhood.