Addition permits in City of Lakewood: fees, timeline & requirements (2026)

When does a home addition need a permit in City of Lakewood?

2021 IRC R105.1 requires permits for "construction, enlargement, alteration, repair, movement, removal, conversion, or demolition" of structures. Additions are never exempt under R105.2. Footprint additions trigger zoning compliance (setbacks, lot coverage, height); vertical additions trigger structural review for the existing foundation/wall framing. WSEC R402-R403 applies to new conditioned area. SEPA threshold typically ≥12,000 sqft total floor area (RCW 43.21C).

How City of Lakewood adopted this rule

The threshold comes from the state code (WAC 51.51), which City of Lakewood adopts by reference in the provision quoted below.

“Pursuant to RCW 19.27.031 , the following codes as amended by the Washington State Building Code Council herein adopted and further amended, shall be collectively known as the Lakewood Building Code: A. The 2021 Edition of the International Building Code (IBC), including Appendix Chapters E, G, and J, published by the International Code Council and amended by the Washington State Building Code Council in Chapter 51-50 WAC, is hereby adopted by reference and as subsequently amended by this chapter.”

Source ↗verified 2026-04-29

What City of Lakewood says in its own permit handout

From Do I Need A Building Permit? (dated May 20, 2025), published by City of Lakewood. This is the jurisdiction's own guidance on its permit process, not the ordinance text — where the two differ, the code governs.

“Examples of Projects That WILL Require a Building Permit: • All residential or commercial additions (adding square footage to existing buildings). • A structure or new impervious surface of ANY size located within the shoreline buffer or in a critical area or their buffers and setbacks. This includes decks and patios under 18 inches in height. • Residential storage buildings over 120 square feet.”

Handout ↗read 2026-09-05

Required submittals

• site plan with north arrow, property lines, setbacks, existing + proposed structures, lot coverage calculation
• floor plan existing and proposed (dimensioned, 1/4" = 1' min)
• elevations all affected sides (existing + proposed, height-to-grade)
• foundation plan + footing details (if footprint addition)
• framing plan (floor + roof + lateral)
• wall section with insulation values per WSEC
• structural calculations (when ≥500 sqft addition or out of IRC prescriptive envelope)
• WSEC compliance form (Energy Code Compliance Certificate)
• Manual J HVAC sizing calculation for new conditioned area
• window/door schedule with NFRC U-factor and SHGC values
• soils report if footing on slope or expansive soils

Inspection sequence

1. foundation/footing
2. plumbing rough-in
3. electrical rough-in
4. mechanical rough-in
5. framing
6. insulation
7. drywall
8. final

Contractor specialties needed

general

Notes & caveats

From Lakewood handout B10 (Residential Remodel): "Structure Addition – Construction of new square footage attached to an existing structure, this may include interior or exterior alterations to the existing structure. This permit type does not include Attached or Dwelling Units (ADU) or habitable, detached structures." Additionally: "For additions or alternations outside of the structure, an additional Shoreline Exemption permit shall be required if the work is within 200ft of the Ordinary High-Water Mark (OHWM). This is not applicable to interior work only."

Addition permit fee — Washington baseline, not City of Lakewood's own schedule

Worked example for a $120,000 home addition project (building permit). Your actual fee scales with project valuation.

Plan-review fee scales with valuation per UBC Table 1-A. State surcharge $6.50 per building permit. Trade permits (E/P/M) separate. We have not read City of Lakewood's adopted fee schedule, so this is not City of Lakewood's fee: it walks the standard valuation table most Washington cities adopt by reference, as a rough guide. The real numbers are in City of Lakewood's fee schedule ↗. Impact/utility fees may apply separately.