Dow Engineering PLLC
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  • Structural Engineering
  • Site Visits
  • Wall Removal Beams
  • Additions Remodels
  • ADUs and DADUs
  • New Custom Homes
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  • Need a PE Stamp
Civil
  • Civil Engineering
  • Stormwater and LID
  • Erosion Control
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  • Utility Design
Dow Engineering PLLC
Home
Book Appointment
Contact Us
F.A.Q.
Forensic
  • Forensic Engineering
  • Code Violation Notices
  • Litigation Support
  • Structural Expert Witness
Structural
  • Structural Engineering
  • Site Visits
  • Wall Removal Beams
  • Additions Remodels
  • ADUs and DADUs
  • New Custom Homes
  • Foundations
  • Need a PE Stamp
Civil
  • Civil Engineering
  • Stormwater and LID
  • Erosion Control
  • Home Site Plans
  • Drainage and Grading
  • Utility Design
More
  • Home
  • Book Appointment
  • Contact Us
  • F.A.Q.
  • Forensic
    • Forensic Engineering
    • Code Violation Notices
    • Litigation Support
    • Structural Expert Witness
  • Structural
    • Structural Engineering
    • Site Visits
    • Wall Removal Beams
    • Additions Remodels
    • ADUs and DADUs
    • New Custom Homes
    • Foundations
    • Need a PE Stamp
  • Civil
    • Civil Engineering
    • Stormwater and LID
    • Erosion Control
    • Home Site Plans
    • Drainage and Grading
    • Utility Design

  • Home
  • Book Appointment
  • Contact Us
  • F.A.Q.
  • Forensic
    • Forensic Engineering
    • Code Violation Notices
    • Litigation Support
    • Structural Expert Witness
  • Structural
    • Structural Engineering
    • Site Visits
    • Wall Removal Beams
    • Additions Remodels
    • ADUs and DADUs
    • New Custom Homes
    • Foundations
    • Need a PE Stamp
  • Civil
    • Civil Engineering
    • Stormwater and LID
    • Erosion Control
    • Home Site Plans
    • Drainage and Grading
    • Utility Design

Structural Engineering for Additions and Remodels

Adding on is often the best way to get more room without moving: a primary suite, a bigger kitchen, a second story on a rambler. Every addition ties new work to a house built under an older code. That is the part we design. Licensed Washington PEs, stamped drawings and calcs for permit. Need drawings and the permit run? Build Sherpas handles plans and permits.

Call Us

What we design

Bump-outs and ground-level additions, second stories, garage additions and conversions, and big remodels with moved walls, vaulted ceilings and new roof lines.

What makes additions tricky

The existing house, new shear walls and hold-downs, new footings beside old ones, and roof tie-ins with snow load on the combined roof.

Fixed price for defined work

Send plans or photos. Defined additions get a clear fixed price. Code, red-tag and open-ended work starts with a short hourly agreement.

SIPs over an existing roof

Existing cabin roof opened up - no insulation in the cavities.
SIPs going on over an uninsulated cabin roof.
Crew setting insulated roof panels.

Planning an addition or remodel? Call.

Call (253) 319-3220 or use Contact Us. Send plans or photos. Defined projects get a clear fixed price; code and open-ended work starts with a short hourly agreement.

Call Us
  • Need a PE Stamp
  • Structural Engr Sumner
  • Pre-Purchase Assessment
  • Bearing Wall Removal
  • Stamped Plans for Permit
  • ADU Structural Engineer
  • Foundation Engineering
  • Home Addition Engineer

Dow Engineering PLLC

16202 64th St E Ste 117, Sumner, WA 98390

(253) 319-3220 · office@dowengineeringpllc.com

Copyright © 2026 Dow Engineering PLLC - All Rights Reserved.

Our family: Build Sherpas, WA Blower Door, MI Elements. Same office in Sumner.

Part of the Dow Engineering family, Sumner, WA

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