576 sq ft Two-Story DADU
with Storage Loft in Puyallup, WA
A two-story DADU with 576 sq ft of living space and a 432 sq ft storage loft above — 1,008 sq ft total under roof. The main level features a dramatic vaulted ceiling reaching 16'-7", an open kitchen/dining area, one bedroom, full bathroom, and a 144 sq ft covered patio. The upper level is split into heated storage (253 sq ft) and unheated storage (115 sq ft), accessed by pull-down stairs. Designed to work with the property's septic system, sized for 5 bedrooms total. Built by Evercrest LLC in Pierce County, WA. Sometimes called a backyard cottage, this detached ADU (DADU) is fully independent from the main home.
Main Floor Plan
Living Room (115 sq ft) — open to vaulted ceiling, height from 8' to 16'-7". Smoke/CO detectors.
Kitchen/Dining (177 sq ft) — open concept. Full kitchen with 160–400 CFM range hood. No garbage disposal (septic).
Bedroom (151 sq ft) — sliding egress window, pocket door. 8' ceiling.
Bathroom (47 sq ft) — full bath with shower. 50 CFM fan vented to exterior.
Covered Patio (144 sq ft) — outdoor living + pull-down stairs to loft.
Storage Loft Plan
Heated Storage (253 sq ft) — min height 4'-4", max 7'-10". Accessed via pull-down stairs through 2'-6" × 6'-0" opening.
Unheated Storage (115 sq ft) — separate zone with attic access. Ideal for seasonal items.
Combined 432 sq ft of loft storage — doesn't count toward living square footage.
Elevations
All four elevations show the two-story profile with a dual-pitch gable roof reaching 17'-3½".
Storage floor at 8'-10", main floor ceiling 8'-0". Hardie plank siding. V12 skylights, H3 and H9 windows.
Weather protection per IRC, continuous gutters, tempered safety glazing, egress windows per code.
Cross Section
Roof: Class A shingles, 15 lb paper, 1/2" sheathing, rafters, R-38 foam board, 1/2" drywall.
Walls: Hardie plank, WRB, R-5 c.i., 3/8" plywood, R-20 fiberglass batt, 2×6 stud, Class I vapor retarder, 1/2" drywall.
Floor: Carpet, 5/8" plywood, R-10 rigid, 10 mil vapor barrier, slab on grade.
R-10 insulated headers. Continuous air barrier foundation to roof.
Foundation Plan
4" slab on grade with #4 rebar @18" OC each way over 6 mil vapor barrier on compacted subgrade.
16 STHD14 holdown points — Seismic Category D design.
24" square × 10" deep footings with 3#4 rebar at six point load locations.
Fully insulated slab. Engineered by Guibin Lu, PE #42309.
Building Specifications
Permit
Approved: September 22, 2025
Permit #: 1059615
Authority: Pierce County
Fire Review: Dec 11, 2025
Reviewed by: Ryan Purcell
Project Team
General Contractor: Evercrest LLC
Architect: Global Precision Designs Inc.
Engineer: Guibin Lu, PE #42309
Understanding DADUs in Puyallup
A DADU (Detached Accessory Dwelling Unit), also known as a backyard cottage, is a standalone residential structure built on the same lot as an existing home. Pierce County allows DADUs on lots with adequate space and utility capacity. In areas with septic systems like this Puyallup property, septic capacity must accommodate the additional dwelling — this project's system handles 5 bedrooms at 600 gallons/day. Evercrest LLC manages everything from design through Pierce County permitting and construction.
Detached ADU (DADU) Construction in Puyallup — FAQ
Detached ADU (DADU) costs in Puyallup and Pierce County range from $200 to $350+ per sq ft. This 576 sq ft two-story DADU was valued at $465,500 including the storage loft. Evercrest LLC provides fixed-price contracts.
Yes, but septic must have enough capacity. Pierce County requires TPCHD approval. This project's septic handles 5 bedrooms at 600 gal/day. No garbage disposal allowed.
Typically 3–6 months. This project was approved Sept 22, 2025, with fire review approved Dec 11, 2025. Evercrest handles all submissions and communication.
Varies by zoning. Storage loft space below habitable ceiling height (under 7') doesn't count toward living area — that's how this project achieves 1,008 sq ft total with only 576 sq ft living space.
Yes. A loft with ceiling below 7' counts as storage, not living space. This project has heated (253 sq ft) and unheated (115 sq ft) storage accessed by pull-down stairs.
Yes — Pierce County (Puyallup, Tacoma, Bonney Lake, Lakewood), King County (Seattle, Bellevue, Renton, Kent), and Snohomish County (Everett, Lynnwood, Bothell). Full-service in all jurisdictions.
Ready to Build Your Backyard Cottage in Puyallup?
Evercrest LLC handles design, engineering, permits, and construction — one team from start to finish.
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