“Architect vs Interior Designer in Seattle: What’s the Difference?

*By David Meade, AIA, NCARB | Piper Cole Architects*

> TL;DR: Architects are state-licensed professionals who can design structural systems, submit permit drawings, and manage construction. Interior designers in Washington State are not licensed by law — meaning they cannot stamp or submit permit drawings for structural work. For cosmetic updates, an interior designer may be all you need. For anything structural, an addition, or new construction, a licensed architect is either legally required or practically essential to keep your project on track.

What Architects and Interior Designers Actually Do (And Where the Overlap Creates Confusion)

The confusion is understandable. Both professions make spaces look and function better. But their scopes are fundamentally different.

Architects design the building itself — floor plans, structural systems, exterior envelopes, code compliance, and the coordination between engineering disciplines. As a licensed AIA member and NCARB-certified architect, I work on everything from the foundation up: sizing structural beams, resolving zoning setbacks, coordinating with civil and structural engineers, and producing permit-ready drawing sets.

Interior designers work inside the envelope that architects define. They select finishes, specify furniture and cabinetry, arrange spaces for flow and aesthetics, and manage procurement. A skilled interior designer brings real value, especially on high-end residential projects.

The overlap — space planning, fixture selection, lighting design — is where homeowners get confused. In our Kirkland and Bellevue projects, we frequently collaborate with interior designers. Each profession handles what it is trained and authorized to do.

Washington State Licensing: Why Architects Are Regulated and Interior Designers Are Not

Washington State takes architect licensing seriously. Under RCW 18.08, it is unlawful to practice architecture, use the title “architect,” or submit architectural drawings without a Washington State license. Every licensed WA architect carries a board-authorized seal with their name, license number, and the designation “Registered Architect, State of Washington.” Firms must also hold a Certificate of Authorization (COA) from WA DOL.

Interior designers operate under an entirely different regime. Washington State does not require a license to practice interior design or use the title “interior designer.” Anyone may call themselves an interior designer and take on projects. Washington does have a voluntary “Registered Interior Designer” (RID) credential — but it is title-protection only, not a practice license. It does not confer any authority to stamp permit drawings.

This is not a criticism of interior designers — it is simply the legal reality homeowners need to understand before they hire.

When Washington Law Requires a Licensed Architect — And When It Doesn’t

Under RCW 18.08.410 and WAC 308-12-340, drawings submitted for a building permit must be stamped by a licensed architect or professional engineer unless an exemption applies.

Key exemptions include:

  • Residential buildings of four dwelling units or fewer (single-family homes, duplexes), regardless of square footage
  • Farm buildings
  • Any structure under 4,000 sq ft total

What this means for Eastside homeowners: a single-family remodel or addition technically falls under the residential exemption. But if structural engineering is involved, a structural engineer’s stamp is required. And for complex additions, custom new construction, or any commercial or mixed-use scope, a licensed architect is functionally required regardless of the exemption.

In practice, Kirkland and Bellevue building departments expect permit drawings that meet code. Drawings that do not will fail plan review, triggering resubmittal cycles that add weeks and real cost to your project.

Project Type Decision Guide: Who You Need for Each Scope

Project Scope Who You Need
Cosmetic refresh (paint, fixtures, furniture) Interior designer only
Non-structural remodel (cabinets, flooring, no walls moved) Interior designer; architect optional
Structural remodel (removing/relocating walls, new openings) Licensed architect + structural engineer
Addition (any size) Licensed architect strongly recommended; structural engineer required
Custom new construction Licensed architect required
ADU / DADU Licensed architect recommended; depends on complexity

We cover the addition decision in depth on our home addition architect page for Redmond and the Eastside. For whole-house projects, see our whole-house remodel overview.

Can an Interior Designer Pull Permits or Submit Drawings in Kirkland and Bellevue?

The short answer is: not for structural work, and not with a stamped set.

Kirkland uses the MyBuildingPermit.com portal, shared by Bellevue, Redmond, Sammamish, and other Eastside cities. Permit applications for structural remodels typically take 4–6 weeks for plan review in Kirkland when documentation is complete. Additions run 8–12 weeks.

An interior designer without architectural training can submit drawings for a non-structural cosmetic remodel. The moment a wall moves, a beam is added, or square footage changes — the drawings need to be code-compliant, structurally coordinated, and reviewed carefully by someone who understands what plan checkers are looking for.

When homeowners hire an unlicensed designer for structural scope, the most common result is a failed first plan review submission, a resubmittal cycle that adds 4–8 weeks, and sometimes drawings that have to be substantially redone. We have stepped in to rescue several Kirkland and Bellevue projects in exactly this situation.

Working With Both: How Architects and Interior Designers Collaborate

On larger remodels and custom homes, having both an architect and interior designer is not redundant — it is the right setup when roles are clearly defined.

The typical handoff works like this:

  1. Schematic design through permit — the architect leads. Floor plans, structural scope, exterior design, permit drawings, and engineering coordination are all in our lane.
  2. Interior design phase — once the architectural drawings are complete and permitted, the interior designer takes the lead on finish specifications, cabinetry details, furniture, lighting plans, and procurement.
  3. Construction administration — the architect monitors code compliance and structural execution; the interior designer coordinates finish installation and owner selections.

The critical mistake we see is homeowners engaging an interior designer first for a project that has significant architectural scope. Starting in the wrong order costs time and money.

Before your first meeting with any design professional, read through our guide on questions to ask an architect in Seattle and how to prepare for your first architect consultation.

What It Costs to Hire an Architect vs. Interior Designer in the Seattle Eastside (2026)

Architect fees (Seattle Eastside):

  • Remodels and additions: 10%–20% of total construction cost
  • Custom new home: 8%–15% of construction cost
  • Plans-only engagement: $5,000–$15,000 typical range
  • Fees increased approximately 7% from 2024 to 2025–2026

Interior designer fees:

  • Hourly: $50–$200/hour depending on experience and scope
  • Some charge per sq ft or as a percentage of furnishings/project budget

Construction cost context: Home additions on the Seattle Eastside run $600–$800 per sq ft in 2026. At those project sizes, architect fees represent a small percentage of total investment — and the cost of a failed permit submittal or missed structural issue far exceeds the fee difference between an architect and an unlicensed designer.

For a full comparison of how architect-led projects are structured, see our post on design-build vs. architect in Seattle.

Why Choosing the Wrong Professional Can Cost You More in the Long Run

We see this pattern in our Kirkland practice: a homeowner hires an interior designer for what they believe is a “simple” addition. The designer is talented at interiors but not versed in Kirkland’s zoning setbacks, structural load paths, or what the building department’s plan reviewers expect in a drawing set.

The result is drawings that fail plan review — sometimes multiple rounds. The homeowner now pays for the original drawings, the redesign, and the delay while their contractor sits idle. In a worst-case scenario, construction begins under a permit that does not reflect the actual scope, creating liability and potential stop-work orders.

The upfront cost of a licensed architect is real. The downstream cost of not having one on the right project is higher.

Frequently Asked Questions

Q: Do I need an architect or an interior designer for a kitchen remodel in Kirkland?

A: It depends on scope. If the kitchen remodel is cosmetic — new cabinets, appliances, finishes, no walls moved — an interior designer or kitchen designer can handle it. If you are removing a wall, relocating plumbing stacks, or adding structural openings, you need a licensed architect and likely a structural engineer.

Q: Can an interior designer submit permit drawings in Washington State?

A: For non-structural cosmetic remodels on single-family homes, yes — the residential exemption under RCW 18.08.410 allows it. For any structural work, drawings must be stamped by a licensed architect or professional engineer. Interior designers in Washington hold no license that grants stamping authority.

Q: Is an architect legally required for a home addition in Bellevue?

A: Single-family residential additions fall under the RCW 18.08.410 exemption, so they are not legally required in the same way as commercial projects. However, additions involve structural engineering, zoning compliance, and permit drawings that must pass Bellevue’s plan review. In practice, hiring a licensed architect is the most reliable way to get through plan review without costly resubmittals.

Q: How much does an architect cost for a home addition in the Seattle Eastside?

A: Expect 10%–20% of total construction cost. Given that Eastside additions typically run $600–$800 per sq ft, architect fees on a 400 sq ft addition might range from $13,000–$25,000 depending on scope and level of service.

Q: Can I hire both an architect and an interior designer for the same project?

A: Yes — and for larger remodels and custom homes, this is often the best outcome. The architect leads through permit; the interior designer leads on finish specifications and procurement. The key is defining scopes clearly up front so there is no duplication or gap in coverage.

Ready to Clarify Your Project Scope? Let’s Talk.

If you are not sure whether your project needs an architect, an interior designer, or both — that is exactly the kind of question we help Eastside homeowners sort out before they commit. Piper Cole Architects serves Kirkland, Bellevue, Redmond, Sammamish, and the surrounding Seattle Eastside.

Schedule a free consultation to discuss your project scope →

No pressure. Just a direct conversation about what your project actually requires.

*Sources consulted:*

  • Washington State DOL — Architect Licensing: dol.wa.gov/professional-licenses/architects
  • RCW 18.08 (Architects): app.leg.wa.gov/RCW/default.aspx?cite=18.08
  • WAC 308-12-340 — Stamping exemptions
  • Kirkland Permit Review Times: kirklandwa.gov/Government/Departments/Development-Services-Center/Permit-Review-Times
  • HomeGuide — Architect Cost 2026: homeguide.com/costs/architect-cost
DM
David Meade, AIA, NCARB
Principal Architect, Piper Cole Architects · Kirkland, WA

David Meade is a licensed architect (AIA, NCARB) with 20+ years of residential design experience across the Seattle Eastside. He has designed custom homes, additions, and ADUs in Kirkland, Bellevue, Redmond, and Seattle. Learn more about David →

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