Buying an El Granada home can involve two different investigations: documenting the property as it exists and establishing what a future project could receive approval to do. The same address may have a County planning case, a building permit and separate district service records. Those entries do not share a single completion milestone. A real detached ADU at 315 San Carlos Avenue, a different issued project on El Granada Boulevard and a constrained planning site farther along San Carlos make the distinctions concrete. Use each file for the question it actually answers.
Match the site before interpreting its records
El Granada’s unincorporated property route is through San Mateo County rather than the City of Half Moon Bay. Start with the complete address, unit identifier and assessor’s parcel number. The County’s public search for 315 San Carlos illustrates why this matters. It returns the El Granada address but also broader property-information matches in the City of San Carlos and a roof record at 315 Sequoia Avenue. Those other results cannot be incorporated into the coastal home’s improvement history.
The correct El Granada property-information entry identifies parcel 047-132-060. Keep that identity beside the unit designation when following the ADU file, because records for the original residence and an additional unit may have different scopes. A parcel match organizes the search but does not certify every feature on the land. Preserve the exact permit number and description. If a current layout appears to differ from the available file, ask which approved revision or separate record addresses the difference instead of treating a search-result count as proof of complete authorization.
Follow an actual detached ADU to its recorded final
BLD2024-01812 identifies 315 San Carlos Avenue Apt B and describes 364 square feet of new detached ADU construction. Its stated scope includes a new concrete slab foundation and electrical, mechanical and plumbing work. The public record currently reads Finaled. Expanding Processing Status and then Inspections shows the workflow marked Finaled on July 7, 2025. That is a specific County completion milestone for this project, checked October 26, 2026.
Keep the milestone narrow. The public summary does not provide an inspection of present condition, a private rental agreement, a guarantee that equipment is unchanged or approval for a further unit. It also does not establish that every earlier feature on the parcel was part of this construction. The portal says permits and approved attachments can be viewed after login; those underlying files were not retrieved here. A purchaser needing approved drawings, individual inspection documents or another completion certificate should request the actual records through the appropriate available route.
The description records resubmittals addressing several review disciplines before completion. Those review exchanges help explain why application, review, issue and final are distinct stages. They are not evidence that the finished ADU has an unresolved defect. For a purchase file, place the documented scope beside the final milestone and the current inspection request. This lets the inspector address today’s accessible condition while the regulatory documents establish the history of the particular improvement.
A district sewer permit answers a separate question
The Granada Community Services District’s April 2025 administrative report lists sewer permit 3266 for an ADU at the same 315 San Carlos address and parcel, dated November 22, 2024. It is a separate agency milestone from the County’s July 2025 final. A sewer permit date should not be presented as the date every building inspection was complete. Likewise, a County planning approval does not itself prove that a water connection is installed or every district requirement is satisfied.
The District table also has a square-foot column showing 5,000 for that entry, while the County ADU description is 364 square feet. Do not call the larger number the unit’s living area. Retain each source’s field label and scope, then obtain the approved area information needed for the property. A table that combines parcel context with a project class can be misread when detached from its heading. Using a column simply because it is numeric can turn a service record into an inaccurate description of the dwelling.
| File | Verified public evidence | What to keep separate |
|---|---|---|
| 315 San Carlos address search | Correct El Granada parcel 047-132-060; broader search also returns other addresses. | Exclude City of San Carlos property matches and 315 Sequoia roof record. |
| GCSD sewer permit 3266 | Same parcel/address, ADU, dated November 22, 2024. | District milestone is not County building final; table area is not ADU living area. |
| County BLD2024-01812, Apt B | 364-square-foot detached ADU; Finaled; inspection workflow final July 7, 2025. | Current condition, actual underlying approved drawings and any later work. |
| 747 El Granada Boulevard Unit B, BLD2023-02279 | Issued ADU record with separate deck/stair scope and related fire-sprinkler record. | Issued does not establish final; deck area is not dwelling living area. |
| 779 San Carlos, PLN2021-00478 | Current planning status Approved; County Board adopted action November 4, 2025. | Planning conditions, coastal appeal action and building completion are separate. |
| Current new-project timing | June cap/waitlist notice plus August 25 County averaging-amendment adoption. | Commission certification, implementation and exact parcel application route still need confirmation. |
Original annotated public-record worksheet, October 26, 2026. Sources: County ADU detail, district report and planning record. No private plans, owner identities or field photographs reproduced.
Compare a finaled project with one still recorded as issued
The actual BLD2023-02279 detail at 747 El Granada Boulevard Unit B currently reads Issued. It describes an 835.66-square-foot detached ADU, a 458-square-foot second-floor deck and new stairs connecting the ADU and main dwelling. The description identifies a related fire-sprinkler record. This project has a different scope and public status from the San Carlos example. Neither the deck area nor the presence of a related record should be converted into an additional living-area or completion claim.
For such a file, ask which inspections and agency confirmations remain, and request the relationship between the approved building scope and related systems. The public status alone does not establish whether a particular element has been constructed, currently works or requires correction. A seller’s construction documents and an appropriate inspection can add that evidence. Keep unresolved steps identified by record and component rather than describe the whole property as either fully complete or entirely unapproved.
Keep the original residence’s history alongside the additional unit’s file. The San Carlos search lists earlier windows or doors, water-heater, roof-repair and kitchen scopes as Finaled. Those historical entries are useful prompts for requesting the corresponding documents, but they do not identify today’s materials or establish remaining useful life. An old roof final should not be advertised as the current roof’s verified installation date without checking later work. Likewise, the additional unit’s newer slab description does not describe the original house’s foundation. Separate the structures and components before planning inspections or describing improvements to a buyer.
Read a planning approval through its site conditions
The County’s current PLN2021-00478 record at 779 San Carlos reads Approved. The Board’s November 4, 2025 action confirms adoption of the planning decision. The case concerns a residence, garage and ADU on a 7,070-square-foot parcel, with constrained siting associated with the Montecito Riparian Corridor. That record supports a site-specific approval history, not a transferable building envelope for another lot.
The Coastal Commission staff report separately recommended a no-substantial-issue finding on an appeal. A staff recommendation and proposed motion are not the Commission’s actual vote. This research did not independently retrieve the final appeal action, building issue or construction final for that site. Request those milestones if they matter to the purchase, along with applicable conditions and recorded restrictions. Avoid using a biological discussion or a setback variance from this file to diagnose or approve a neighboring property.
Confirm today’s route for any proposed additional unit
The County’s June 2026 notice distinguishes planning applications, a waitlist and active building applications from new housing-unit building applications affected by the Urban Midcoast cap. A later August 25 Board action adopted an averaging amendment for Coastal Commission review and certification. County adoption does not by itself establish completed certification or a parcel’s available application slot. Confirm the current implementation with the County rather than promise either automatic reopening or a blanket date for every project.
Older completed work is not evidence that a new proposal receives the same timing. Also distinguish a new dwelling from a repair or alteration to an existing home before applying the notice. Complete the purchase research with the precise proposed scope, actual parcel and relevant service providers. The County map route can help identify service districts, while the actual agency file establishes project requirements. Return to the El Granada guide, San Mateo County guide and buying process to coordinate the existing-home and future-project decisions with the appropriate reviewers.
