Carnation DADU Permits: What You Need to Submit
Carnation’s published ADU sequence begins with water and sewer availability certificates, then survey and design work. The application needs a site plan connecting the proposed cottage to the main house, parking and pedestrian access.
Sources checked November 5, 2026. Confirm the requirements for your parcel with its permitting authority.
What is Carnation’s suggested application sequence?
- Obtain water and sewer availability certificates.
- Arrange the survey and design information needed for the proposal.
- Consider the city’s recommended pre-application conference.
- Submit the building application, site plan and applicable fees.
This sequence comes from the city ADU FAQ. The pre-application conference is described as optional but highly recommended. Use it to resolve a particular issue, such as how the proposed cottage connects to services, rather than arriving with an already-fixed design.
Official guidance: City of Carnation ADU questions and application steps.
What does the site plan need to show?
| Plan element | Why it matters to your layout |
|---|---|
| Both dwellings and other structures | The cottage is reviewed in relation to the existing property. |
| Parking and vehicle access | A new entrance must work alongside the principal home. |
| Pedestrian walkway | Show the route from the street or alley to the ADU entrance. |
| Underlying-zone setbacks | Draw the building envelope before fixing the footprint. |
The city also requests floor areas, bedroom locations and elevations with dimensions. Prepare the site and building drawings as one coordinated package. A change in cottage location should appear everywhere that location is shown.
Official guidance: City of Carnation ADU questions and application steps.
Which dimensions and surface limits should be checked?
The FAQ directs applicants to CMC 15.48.070 and the ADU standards in Chapter 15.46. Confirm the current zone, floor-area calculation, lot coverage and impervious-surface requirements before treating an open part of the yard as buildable.
For the design discussion, draw existing paving and the new paths alongside the cottage. Keeping surfaces visible makes the coverage conversation more useful than checking the building alone. Clearly label proposed removals as well as additions.
Official guidance: City of Carnation ADU questions and application steps.
How do you avoid a disconnected application?
Use the same floor area, bedroom count and service approach in the utility request and building package. Keep the city’s response with the plans and identify who will answer comments from each reviewing department.
TimberworX offers a free consultation for Carnation DADU planning. Detailed survey coordination, design, research and budgeting are paid preconstruction services. Start with the property records and the questions that could change the proposal.
A few things to know
Is a pre-application conference required in the published FAQ?
The FAQ describes it as optional but highly recommended.
Can I submit only the cottage floor plan?
The published package also calls for site and elevation information showing the relationship to the existing property.
Keep planning
Carnation DADU Water and Sewer: Do You Need a New Meter?
Carnation’s ADU guidance explains availability certificates, use of the primary home’s service line and when a new water meter affects charges.
Do you need a survey for a DADU?
Understand how a DADU site plan differs from a survey and which property information supports design and permit review.
What permits do you need for a DADU?
A practical DADU permit checklist covering site plans, building review, utilities, trade permits and final inspections.