ADU Builder in Glendora, CA: Permits, Pre-Approved Plans and Costs

Pre-approved ADU plans through the Glendora Planning Division

The Glendora Community Development Department lists pre-approved ADU plans on the city ADU and SB 9 page. As of the March 2026 handout the city lists at least two plans: Plan ID BPC24-0004, a 400 square foot ADU from Mei Li Homes LLC, and Plan ID BPC24-0010, a 495 square foot prefab ADU from Abodu Inc. in multiple finish and fascia options. L Square reviews the lot for setbacks, slope, and utility route before recommending any plan. Contact the Glendora Community Development Department, 116 E. Foothill Boulevard, Glendora, CA 91741 to confirm the current plan list and any fees that apply when you reference a Plan ID on your application.

Glendora permit process and 60 day state clock

Glendora ADU applications go to the Community Development Department, Planning Division. California Government Code Section 66317(a)(2)(A) requires a completeness decision within 15 business days, and Section 66317(a)(3) gives the city 60 days to approve or deny a complete application when an existing single family home is on the lot. If the city does not act within 60 days, the application is deemed approved under state law, less any applicant requested delay. Glendora does not require a public hearing for a ministerial ADU that meets the state standards and the local development rules in Glendora Municipal Code Section 21.04.040. L Square prepares the submittal package, schedules the intake, and tracks the 15 business day and 60 day clocks so the project does not slip into the next planning cycle.

Size, height, and setback rules in Glendora

Glendora Municipal Code Section 21.04.040 and the March 2026 ADU handout cap a detached ADU at 1,200 square feet of floor area on a lot with an existing or proposed primary dwelling. The state floor in Government Code Section 66321(b)(2)(A) and (B) is 850 square feet for a studio or one bedroom detached ADU and 1,000 square feet for a multi bedroom detached ADU, and Glendora cannot undercut that floor. Maximum height is 25 feet, not to exceed 2 stories, and minimum side and rear setbacks are 4 feet in single family zones and 3 feet in Rural Hillside Residential. Front setback follows the zoning district. An ADU within 6 feet of the main residence is considered attached for height and FAR purposes. Government Code Section 66323(a)(2) creates a separate ministerial path for an 800 square foot detached ADU with 4 foot side and rear setbacks, and Section 66314(d)(7) lets the city clear existing structures and same location rebuilds from the 4 foot setback ceiling.

Parking, JADU, and legalization for older Glendora ADUs

The March 2026 handout states the City of Glendora does not require off street parking for ADUs or JADUs under state law, but off street parking is strongly encouraged because of the city's overnight street parking rules. Government Code Section 66314(d)(10) caps required parking at one space per bedroom or per unit, Section 66314(d)(11) bars the city from requiring replacement parking when a garage, carport, or covered parking structure is converted to an ADU, and Section 66314(b)(2) lets a local agency fully exempt ADUs from parking. Section 66322(a) lists six situations where parking may not be imposed, including ADUs within one half mile walking distance of public transit. A Junior ADU is capped at 500 square feet, must be inside the primary home, and requires owner occupancy in either the primary home or the JADU, with a recorded deed restriction before the permit issues. For older unpermitted units, the Glendora Planning Division handles the state legalization path and the recorded covenant paperwork at intake; L Square verifies the unit against current code and the recorded covenant before any close in.

Impact fees, preemption, and California state law ceiling

Under California Government Code Section 66311.5(c)(1), Glendora, special districts, and water corporations shall not impose any impact fee on an ADU that has 750 square feet of interior livable space or less. Any impact fees charged for an ADU larger than 750 square feet are charged proportionately in relation to the square footage of the primary dwelling. Section 66311.5(b) treats an ADU as not a new residential use for water and sewer connection fees, unless the ADU was built with a new single family home. Section 66325(a) states the ADU approval article supersedes any conflicting local ordinance, and Section 66325(b) does not authorize stricter standards than state law, only less restrictive ones. When the city overlay adds a rule that conflicts with state law on size, parking, setbacks, or approval timelines, state law controls. L Square confirms the local schedule with the Glendora Planning Division before the submittal package is final.

Cost ranges and what is included at L Square

L Square model prices for ADUs that meet the 1,200 square foot state ceiling start at $180,000 for the smallest prefab layout, with $240,000, $295,000, and $354,000 covering the larger 2 bedroom plans published on lscontractor.com/adu-cost-orange-county/. Those prices are the same for Los Angeles County cities including Glendora, and they cover design, engineering, permits, and build for the published plan footprint. Site specific costs such as slope work, utility trenching, retaining walls, and code upgrades for Very High Fire Hazard Severity Zones are quoted after the lot review. Confirm the final number with the Glendora Planning Division for impact fees, school fees, and water meter fees. L Square holds California Contractors State License Board number 1095476 and writes every proposal in writing before any work starts.

Official Glendora ADU sources

• The Glendora ADU and SB 9 landing page references Glendora Municipal Code Section 21.04.040 for complete ADU, JADU, and guest house standards, lists the Community Development Department, Planning Division at 116 E. Foothill Boulevard, Glendora, CA 91741, with a direct planning line and the planning division email on the cover page, and lists at least two pre-approved ADU plans: Plan ID BPC24-0004, a 400 square foot ADU from Mei Li Homes LLC, and Plan ID BPC24-0010, a 495 square foot prefab ADU from Abodu Inc. in multiple finish and fascia options. Official source
• California Government Code Section 66317(a)(3) gives the city 60 days to approve or deny a complete ADU application when an existing single family home is on the lot, and Section 66317(a)(2)(A) requires a completeness decision within 15 business days. Official source
• California Government Code Section 66314 limits a detached ADU on a lot with an existing or proposed primary dwelling to 1,200 square feet of floor area, and Section 66314(d)(7) lets the city clear existing structures and same location rebuilds from the 4 foot setback ceiling. Official source
• California Government Code Section 66311.5(c)(1) bars a local agency, special district, or water corporation from imposing any impact fee on an ADU with 750 square feet of interior livable space or less, and impact fees above that floor are charged proportionately in relation to the primary dwelling square footage. Official source
• California Government Code Section 66325(a) states the ADU approval article supersedes a conflicting local ordinance, and Section 66325(b) does not authorize stricter standards than state law, only less restrictive ones. Official source