What Is Title 24?

Somewhere in your plan set is a document with an intimidating name: the Title 24 energy compliance report. Here's what it is, why it exists, and why it's less scary than it sounds.

The plain-English version. Title 24 is California's building energy code. Before a permit is issued, your project must prove on paper that it will be energy-efficient — insulation, windows, heating and cooling, water heating, lighting, and (for new construction) solar all get evaluated together. An energy consultant runs your design through certified software, and the output is the report in your plan set.

The energy budget idea. The code doesn't dictate every choice; it sets an overall energy budget for a building of your size and climate zone. Strong performance in one area can offset weaker performance in another — great insulation can buy back bigger windows; an efficient heat pump can carry an average wall. This flexibility is why the report is modeled, not checklisted, and why your designer can usually protect the features you care about.

What it means for your ADU, concretely: insulation levels well above old-house standards; dual-pane low-e windows; almost always heat-pump equipment for space and water heating (Module 7's advice was secretly Title 24's advice); LED lighting; and solar for new construction (lesson 7.9). Notice: nothing exotic. Modern construction hits these marks routinely.

The quiet upside. Homeowners meet Title 24 as bureaucracy and live with it as comfort: ADUs built to current code are noticeably quiet, thermally stable, and cheap to run — tenant utility bills of $40–$80/month where an old house runs $250. For rentals, that's a marketing line; for family, it's daily quality of life.

Cost and process recap: $500–$1,500 for the report (Module 6.5), a few days' turnaround, handled between your designer and the consultant. Your involvement: approximately zero — unless you want that wall of west glass, in which case the energy model is where that negotiation happens.