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Wood-frame structural calculations

Wood-frame calcs for California homes and ADUs.

Work through gravity, wind, seismic, shear wall, diaphragm and footing checks in 11 steps, then print a calculation report for the Engineer of Record to review and stamp.

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Mitchell ADU · Shear wallsSample project · Live engine

Step 08 · Lateral

Shear wall schedule

SDPWS 2021 · Longitudinal
Line / Wall Lengthft-inSW type Hold-down Strap UtilizationD/C
A.1 / 18'-2"SW1HDUE3CS16OK0.73
A.1 / 25'-0"SW1HDUE3CS16OK0.73
C.1 / 311'-0"SW1HDUE3CS16OK0.87

Line A.1, Wall 1 (8.17 ft) → SW1, HDUE3, CS16

Sample project · AI inputs simulated · Engineer review requiredInspect the calculations

Code & scope

What the calculations cover today

CoveredNot covered yet
ASCE 7-22 — Wind and seismic loadsSteel design
SDPWS 2021 — Wood shear walls and diaphragmsConcrete design
NDS 2024 — Beams and stud wallsMulti-span beams
2025 CBC — California Building Code provisionsDWG output
Footings — Pad and spread footings

Workflow

The same 11 steps on every project

  1. 01CoverProject data, code editions and design criteria.
  2. 02Vertical LoadsDead, live and snow loads by assembly.
  3. 03BeamsBeam and header sizing to NDS 2024.
  4. 04WindASCE 7-22 wind pressures for the main system.
  5. 05Seismic CsSeismic response coefficient and base shear.
  6. 06Floor WeightSeismic weight of each level.
  7. 07Shear LineWind and seismic forces distributed to shear lines.
  8. 08Shear WallsSDPWS 2021 wall type, hold-downs and straps.
  9. 09DiaphragmDiaphragm shear and nailing.
  10. 10FootingsFooting size from bearing pressure.
  11. 11Stud WallStud axial and bending check to NDS 2024.

Report preview

Read the output before you sign in

View sample calculation report Letter-size calculation package generated from the sample project. Engineer seal area is left blank.View sample proposal Scope, exclusions and fee tables built from the same project data.

FAQ

Questions engineers ask first

Which codes are used?

ASCE 7-22 for wind and seismic loads, SDPWS 2021 for shear walls and diaphragms, NDS 2024 for beams and stud walls, and the 2025 CBC. Steel and concrete design are not covered yet.

Who stamps the calcs?

The Engineer of Record reviews and stamps; the software never inserts a seal. The seal area on the report is always left blank.

Can I edit every input?

Yes. Every input can be overridden, and each value carries a source label so a checker can see where it came from.

Where do hazard values come from?

USGS ASCE 7-22 web service or the uploaded ASCE Hazard Report. The source is shown next to each value.

Is my data private?

Project data stays in your signed-in account and is not shown on public pages. The live demo uses a sample project, so you can evaluate the tool without entering client data.