MEP Plans in El Dorado Hills, CA

El Dorado Hills project facts we design around

County	El Dorado County (unincorporated)
Title 24 climate zone	Climate Zone 12, confirmed by ZIP for every project
Electric utility (most addresses)	Pacific Gas and Electric (PG&E)
Permits issued by	El Dorado County Planning and Building Department – Building Division
ADU permits issued, 2021–2025	51
ADU approval timeline	Approve or deny within 60 days of a complete application (state law)

ADU building activity in El Dorado Hills

El Dorado County issued 51 ADU building permits from 2021 through 2025 for addresses in El Dorado Hills, based on the county's reports to the state. Permits went from 6 in 2021 to 17 in 2025.

2021	2022	2023	2024	2025
6	7	8	13	17

Source: California Department of Housing and Community Development, Annual Progress Report data (ADU building permits by year).

Title 24 in Climate Zone 12

• Windows: U-factor 0.27 or lower and solar heat gain coefficient (SHGC) 0.23 or lower, with total window area up to 20% of floor area (west-facing up to 5%).
• Whole-house fan required (at least 1.5 cfm per square foot of floor area); units of 500 sq ft or less are exempt.
• Cool roof required: steep-sloped roofs need aged solar reflectance 0.2 or higher and thermal emittance 0.75 or higher.
• Solar PV sized by the CEC formula kW = (floor area x 0.613) / 1000 + 1.4; no PV is required if that is under 1.8 kWdc, which for a single ADU works out to about 653 sq ft or smaller.

Climate Zone 12 requirements in full →

HVAC design for El Dorado Hills

The California Energy Commission's design-day data for El Dorado Hills gives the outdoor conditions a Manual J load calculation uses: a summer design temperature of 98°F and a winter design temperature of 24°F.

Summer design (1%)	98°F dry bulb / 69°F wet bulb
Winter design (median of extremes)	24°F
Daily temperature range	36°F
Elevation	673 ft

Both seasons matter here. The heat pump is usually sized for the 98°F cooling condition and then checked to confirm it still covers the heating load at 24°F.

Electrical service from Pacific Gas and Electric (PG&E)

If the load calculation shows you need a service upgrade, a second meter or a relocated service, Pacific Gas and Electric (PG&E) handles that through its Your Projects portal, separately from the building permit.

ADU electrical service with Pacific Gas and Electric (PG&E) →

Plumbing and sewer

The plumbing plan shows the route, slope and cleanouts of the connection to the existing sewer lateral or septic system.

Pricing is flat statewide: ADU plans from $995, full ADU MEP package from $2,295, Title 24 add-on $240. See what's in a complete ADU MEP set.