2019 Building Code

More efficiency, lower energy bills

Dan Kegel



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Triennial Cycle

The 1973 energy crisis was a wake-up call that set California on a path towards energy independence.

Every three years, the state and stakeholders update the state building energy code, keeping costs in mind.

The gradually increasing efficiency of new California buildings insulates residents from rising energy prices.

Since the last update, technology has advanced…

Big changes for 2020

The 2019 code (effective 2020), parts 6 and 11, include:

  • A bit more insulation in windows, exterior walls, doors, floors, and roof
  • A bit more efficiency in A/C fans
  • Appropriately sized solar power, optional battery
  • More heat pump water heaters
  • More EV readiness

Climate Zones

** Title 24, Part 6 requirements vary by “climate zone”

Venice is Zone 6, downtown LA is Zone 8.


Better insulation

150.1[c]1 page 279 in 2019 vs page 248 in 2016
Table 150.1-A page 287 in 2019 vs. page 254 in 2016

  • Windows & Doors (notes)
    • Windows <= U-0.30 (was 0.32) (or 0.24, 150.1[c]8)
    • Window SHGC <= 0.23 (was 0.25)
    • Doors <= U-0.20 (new requirement)
  • Walls** <= U-0.48 (was U-0.51) (Venice: 0.65) (notes)
  • Attics (but not in LA or Venice) (notes)
  • Insulation must undergo QII, HERS (notes)

Heat Pump Water Heaters

Heat pump water heaters can be 3.5x more efficient, and can provide some electricity storage.
Utilities are starting to offer incentives to switch.

  • A 240V line to the water heater is now required (150.1[n]1, page 267)
  • Electric heat pump water heaters are now allowed (150.1[c]8, page 282)

Water heater carrots & sticks

150.1[c]8 (page 282) encourages very efficient
(e.g. NEEA Tier 3 or tankless) water heaters.

Using an old-fashioned water heater may require:

  • more efficient windows (U-0.24)
  • Compact Hot Water Distribution (no T’s, short runs)
  • Drain Water Heat Recovery (shower heat prewarms)
  • or an (unobtainable?) 60-gallon WH < 75,000 BTU

See also Stakeholder notes, draft changes

Solar roofs

New section 150.1[c]14 (page 284)

The formula for how much solar new houses need is:

kW PV = (CFA x A)/1000 + (# units x B)

where A and B are given by Table 150.1-C on page 286

e.g. a 5400 sq ft Venice duplex needs 5.7 kW of solar

A battery can reduce solar requirement (page 285)

Batteries charged from solar can get federal tax credit

Solar awnings can save space and keep house cooler

Bottom line for Part 6 changes

Cost: $9,500 (much lower if solar is leased)

30 year savings: $19,000

Increased comfort, lower energy bills

See FAQ at energy.ca.gov/title24

Here come the EVs

Dan Neil (WSJ) says EVs are cheaper and better than normal cars, and he’s not looking back.

Tennants will want to plug their car in. Let them.

EV prices declining, expected to be cheaper by 2023

Plug or hardwired charger?

Single-family houses only need a 240v outlet

Multifamily houses should plan for hardwired chargers

Title 24, Part 11: EV Readiness

Section parking spots ready for EV chargers

See also CARB cost analysis

Note: LA may require 20% or more soon

EV Readiness, cont’d

Section Total panel capacity required

EMS = Energy Management System or “smart charger”

See PG&E’s Approved EV Charge Network vendors

For further reading