Core TradesQuestion 159 of 700
Under current California Energy Code prescriptive requirements, wood-framed ceiling/attic insulation in most climate zones must reach a MINIMUM of about:
a.R-13
b.R-19
c.R-30
d.R-38 or higher
Explanation
Prescriptive ceiling insulation in most California climate zones is R-38 or greater, because the roof/attic is a major heat-loss and heat-gain surface. R-13 and R-19 are typical wall values, and R-30 is below the prescriptive ceiling requirement for most zones.
Law Reference: 2025 CA Energy Code §150.1Practice all 700 questions free — no signup required.
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