Chino/Chino Hills commands the highest rents in the service area, which strengthens the financial case for larger ADU sizes. The 2-bedroom at 850–900 sf is more economically compelling here than anywhere else we build — a 2BR in Chino Hills earns $2,600–$3,000/month from professional tenant households, on approximately $45,000–$55,000 more construction cost than a 1BR. The view premium on hillside Chino Hills lots further strengthens the 2BR case. On standard City of Chino planned community lots, the 1BR at 650 sf remains the yield-optimized choice.
The 750 SF Threshold — Still Relevant in High-Rent Markets
Even in Chino Hills where rents are highest, the 750 sf impact fee exemption matters. City of Chino and City of Chino Hills both impose school district and other impact fees above 750 sf. In Chino Hills, those fees run $12,000–$20,000 for ADUs over 750 sf — a real cost that affects the size decision. We design to 749 sf for cost-optimized 1BR projects, and evaluate the 2BR case on larger lots where the rent premium justifies the fee exposure.
Lot-Specific Size Constraints
City of Chino planned community lots (6,000–10,000 sf, 40% coverage): Standard coverage math — similar to Temecula. Typical buildable footprint for ADU: 600–1,100 sf after accounting for main house coverage.
City of Chino Hills hillside lots: Size is constrained not just by coverage but by usable flat area. Steep slope cuts significantly into what appears on paper to be a large lot. A 12,000 sf Chino Hills lot with 30% slope gradient may have only 3,000–4,500 sf of usable flat area. Geotechnical assessment reveals actual buildable area — often less than the lot dimensions suggest.
Carbon Canyon lots: Some of the most restricted in the service area. Narrow road access, wildfire clearance requirements, and extreme slope grades constrain ADU size and placement significantly. Carbon Canyon projects require careful feasibility assessment before design investment.
The 2BR Case in Chino Hills
Chino Hills is one of two markets in our service area (along with Temecula's best neighborhoods) where a 2BR ADU at 850–900 sf consistently outperforms the 1BR on a risk-adjusted basis. The professional household tenant demographic — dual-income couples, small families targeting the school district — specifically seeks 2BR units and will pay $2,600–$3,000/month in Butterfield Ranch or The Preserve. The construction premium for a 2BR over a 1BR is approximately $45,000–$55,000 on a Chino Hills lot. The rental premium is approximately $500–$600/month, or $6,000–$7,200/year. Payback on the size upgrade: 6–9 years. Plus the 2BR appraises stronger under the income approach.
View Units — The Chino Hills Size-Premium Interaction
On hillside Chino Hills lots with valley views, a well-oriented ADU with a covered deck or patio takes the view premium from the rental market ($300–$500/month) AND justifies a larger unit to house tenants who are paying for the experience. A 850 sf 2BR with view and covered deck in Butterfield Ranch commands $3,000–$3,400/month — returns that make even higher construction costs on hillside lots financially sound over a 10-year hold.
Which city, which lot type, fire zone status, HOA constraints, and target tenant all feed into the optimal size recommendation. The free consultation covers all of this — including the 2BR vs. 1BR return comparison for your specific parcel.
Get Size Recommendation →