CodeCraft Pro — Interactive Stair Stringer, Rafter, Railing & Shop Plan Suite

Code Standard:

Load Scenario / Test Code Break:

Precision Framing Dials

Use sliders or ▲/▼ micro-steppers for exact job-site layout

ⓘ Field Guide: How Rise, Run & Bottom Drop Work Click to expand ▾

Total Rise: Measure vertically from finished lower floor to finished upper floor. Divide by 7.75" (IRC max) and round up to find the minimum riser count.

Bottom Riser Drop: Because finish treads add thickness to every step, the bottom of the stringer must be trimmed by 1x Finish Tread Thickness so the first step does not end up taller than the rest (violating the 3/8" uniformity limit).

RISE

Total Floor-to-Floor Rise 9'-0" (108.000")

108"

Micro-Adjust:

Total Riser Count (Steps) Unit Rise: 7.200" (7-3/16")

15

Step Count Adjust:

RUN

Unit Tread Depth (Nosing-to-Nosing) IRC Min: 10" | IBC Min: 11"

10-1/2"

Micro-Adjust:

Room & Spatial Constraints Max horizontal run & room width envelope

ⓘ How Room Constraints Auto-Snap Landings & Treads Expand ▾

Enter your total room length (including the mandatory 36" bottom landing clearance per IRC R311.7.6) or max stair run. Clicking Snap Stair to Room Space calculates whether a straight flight fits, adjusts unit tread depth down to the 10" minimum if needed, or automatically folds the stair into a 90° L-Turn or 180° Switchback U-Landing when the room is short.

Max Stair Run Space Available: 168" (14'-0")

Total Room Length (204")

Incl. 36" landing

Room Width (96")

Fits U/L turn

Landing Configuration

Lower Flight Risers 8 steps

Lumber, Saw Notch Method & Headroom

Notch Inside-Corner Cutting Method (IRC R502.8.1):

ⓘ Why Circular Saw Over-Cuts Fail Framing Inspection Expand ▾

A 7-1/4" circular saw blade set to cut 1-1/2" lumber exits the bottom face 1-1/4" behind the top entry line. Running the circular saw until the bottom of the blade reaches the notch corner slices 1-1/4" past the crotch on both faces, shrinking your effective throat spine by 1.25" and creating a sharp cross-grain crack starter that splits under foot load. Always stop at the pencil line and finish with a handsaw or jigsaw!

Stringer Lumber Stock

Nosing (1")

Finish Tread (1")

Stair Width (36")

Well Opening (126")

Upper Floor (11.5")

Live Closed-2D Stringer, Square Buttons & Saw Stop Blueprint ALL CODES PASS

Switch between Full Headroom Elevation, Throat Zoom, and Framing Square Brass Gauge + Circular Saw Guide

Unit Riser Cut 7-3/16" 7.200" (15 risers)

Bottom Riser Height 6-3/16" 1" drop for finish tread

Net Throat (After Saw) 5-3/8" Min req: 3.50"

Stringer Board Length 15'-2" Buy 16ft stock (3 req)

Stair Material Takeoff & Framing Square Brass Gauge Settings

Tongue Gauge: 7-3/16" | Blade Gauge: 10-1/2"

Live IRC / IBC Code Compliance Audit & Why Adjustments Fail

2R + T = 24.9" (Ideal Comfort)

Bearing Support Type:

Load Rafter Scenario / Test Code Break:

Rafter, Bird's Mouth & Tail Dials

Adjust pitch, span, structural ridge & fascia/soffit cuts

ⓘ Field Guide: HAP, Heavy Ridges (>3-1/2") & Saw Over-Cuts Click to expand ▾

Structural Ridge Deduction: Multi-ply LVL or glulam ridges often measure 3-1/2", 5-1/4", or 7" thick. Always deduct Half_Ridge / cos(θ) from the theoretical centerline rafter length.

Never Over-Cut the Bird's Mouth: Running a 7-1/4" circular saw past the seat/heel intersection slices 1-1/4" into the cantilevered throat right over the bearing wall plate—creating a split-grain hinge under snow load.

PITCH

Roof Pitch (Rise per 12" Run) Plumb: 33.69° | Seat: 56.31°

8 / 12

Pitch Adjust:

Building Outer Wall Span Half-Span Run: 144.000" (12'-0")

24'-0" (288")

Micro-Adjust Span:

Roof Length (32'-0")

Rafter O.C. Spacing

SEAT

Bird's Mouth Level Seat Cut Heel Plumb Cut: 2-3/8"

3-1/2"

Micro-Adjust Seat:

Bird's Mouth Corner Saw Cut Method (IRC R802.7.1):

Rafter Stock, Heavy Ridge, Overhang & Fascia/Soffit

Rafter Lumber Size

Wall Top Plate Width

Overhang (16")

Ridge Thick (1-1/2")

Rafter Tail / Soffit Style

Fascia Deduct (1-1/2")

Fascia Tip Cut (5-1/2")

Run-Long Extra (0")

Bird's Mouth, Square Buttons & Rafter Length Map ALL CODES PASS

Shows HAP, Heel/Seat Cut, Circular Saw Over-Cut Kerf, Tail Geometry & Framing Square Gauges

Height Above Plate (HAP) 8-3/4" Plumb depth: 11-1/8"

Heel Plumb Cut / Seat 2-5/16" Seat cut: 3-1/2" level

Perp. Notch vs D/4 Max 1-15/16" Max D/4: 2.31" (2-5/16")

Total Rafter Stock Length 15'-11" Ridge-to-plate: 14'-4"

Rafter Station Map & Roof Framing Material Takeoff

Order 16'-0" Lumber Stock

Live IRC R802.6 & R802.7.1 Bird's Mouth Code Audit

Framing Square: 8" Tongue / 12" Blade

Railing & Baluster Field Engine

Presets:

1. Rake-to-Landing Rail Transition

2D Origin (0,0) at top step nosing (IRC R311.7.8 & R312.1)

ⓘ Field Guide: Goosenecks vs. Natural Pitch Intersection Click to expand ▾

When a 34" stair rake rail meets a 36" level landing guardrail, the sloped rail must travel X = (36 - 34) / (Rise / Run) past the top riser to reach 36" naturally. Centering the newel post at 0" forces a 2" vertical gooseneck jump; shifting the newel post into the landing by Natural X eliminates the gooseneck.

Unit Rise (7-1/2")

Unit Run (10")

Rake Rail (34")

IRC R311.7.8: 34"–38"

Landing (36")

IRC R312.1.2: Min 36"

Newel Post Offset from Top Riser Positive = into landing | Negative = down onto tread

0"

Micro-Adjust Offset:

2. Baluster Spacing Engine (4" Sphere Rule)

Side/Edge marks, Center marks & Open-Tread Notched Balusters

ⓘ Field Guide: Side Marks & Open-Tread Notched Balusters Click to expand ▾

Side / Edge Marks vs. Center Marks: In the field, scribing the leading edge and trailing edge of each baluster directly from a hooked tape measure is faster and avoids center-transfer errors.

No Bottom Guard Rail (Notched into Stair Treads): On open-tread stairs without a bottom shoe rail, balusters notch or dovetail directly into the horizontal stair tread. Because the top rake rail climbs at Rise / Run across each tread, every baluster on a step has a different cut length: L_i = H_rail_base + (Position_from_Nosing × Rise / Run) + Tread_Notch_Depth.

Inside Distance Between Posts (Level Run) 7'-0" (84.000") clear rail span

84"

Micro-Adjust Run:

Baluster Width / Thickness

Max Gap (3-7/8")

Bottom Mounting Style

Tread Notch (3/4")

Tape Measure Origin

Top Rail / Shoe Style

Live Sloped Stair Baluster & Rail Transition Visualizer CODE COMPLIANT

Shows true stair pitch angle, tread-notched balusters vs. bottom rail & 4" sphere test

Natural Intersection X 2-11/16" 2.667" past top riser

Newel Fitting Delta +2" Rake @ Newel: 34"

Baluster Count & Gap 3-11/16" 16 balusters (3.676" gap)

O.C. Spacing / Fillet Cut 4-15/16" Fillet cut: 3-5/8" (-1/16")

Field Tape-Measure Layout Marks (Side Edges vs. Centers)

Rails naturally intersect 2-11/16" (2.67") past the top riser. Requires a 2" up-easing/gooseneck at the newel post.

Level Run

Direct-to-Tread Notched Baluster Pin/Cut Lengths (Per Step): Top Plumb Miter: 36.87° | Tread Notch: 3/4"

Baluster Leading & Trailing Side Edge Marks on Tape Measure:

Locked Job-Site Blueprint & Material Estimator

2D Framing Shop Plan, Square Button Setup & Consolidated Material List

Automatically compiles your active Stair Stringer, Roof Rafter, and Railing/Baluster specs into a multi-view shop drawing and lumber yard order sheet.

Architectural Framing Shop Sheet (Stairs, Rafters, Square Buttons & Code Stamp)

IRC 2021 / 2024 VERIFIED

Consolidated Lumber & Hardware Takeoff List (BOM)

Includes +10% waste recommendation

Module	Material / Framing Member	Nominal Size & Stock	Exact Qty	Cut & Installation Spec

Framing Square Gauge & Saw Stop Summary

Built-In Carpentry & Code Curriculum

Interactive Framing & Code Compliance Mini-Course

Work through the 5 interactive field modules, launch live laboratory presets directly into the calculators, and complete the 6-question Inspector Certification Quiz.

Course Progress Module 1 of 5 | Quiz: 0/6

Job-Site Code Inspector Certification Quiz

Test your mastery of IRC R311.7 stair geometry and IRC R802.7.1 bird's mouth limits