Ignotix — Rafter Geometry Studio

Enter project dimensions to calculate common-rafter geometry, including line length, plumb angle, birdsmouth/HAP, tail and overhang. The drawings, templates, quantities and pricing are reference outputs generated from user-provided dimensions; member selection, connections and project-specific conditions are outside this bounded reference geometry workflow.

CNC Rafter pitch & cuts snap ¼″

RISE /run

RUN unit

MEMBER—

PITCH—

LINE LEN—

PLUMB CUT—

HAP—

FASCIA CUT—

Snap

RISE/RUN set the pitch — drag the gold handle on the pitch triangle, or type here. Member, tail/fascia cut, seat & soffit are user‑definable in the panels below.

01 Pitch & span

Unit rise (per run)

Unit run

Building span (total)

Building length (opt.)

Stock supplier

Pitch reads as rise/run (e.g. 6/12). Common run = span÷2 − ½ ridge.

01b Roof pitch

Pitch — rise per 12″ of run

—

Sets the unit rise so the common pitch equals the chosen X∶12. Steps 1–12.

02 Member

Ridge thickness (in)

Rafter stock

Spacing (in o.c.)

Saw max miter °

Saw max bevel °

Editable saw envelope only; it does not change the geometry. The cut reference flags settings outside your machine travel instead of implying the saw can make them directly.

03 Bearing & tail

Seat / plate width (in)

Overhang — horizontal (in)

Tail cut

HAP reference (in)

Birdsmouth seat and HAP are geometric outputs from the entered stock and seat dimensions. Material capacity and connection performance are not evaluated.

04 Fascia & soffit

Fascia material

Fascia depth (in)

Soffit material

Fascia thickness (in)

Soffit run (horizontal underside) = overhang − fascia thickness.

05 Pricing & waste

Waste (%)

Global markup %

Per-line in-house $ and markup % are set in the take-off table below; global markup % overrides every line. Outgoing = in-house × (1 + markup).

Rafter elevation

R—

1:1 cut templates

06 Solved member

Material take-off & pricing

In-house cost in red · outgoing (sell) in black.

Estimate / Export

Reference geometry only. Outputs are generated from user-provided dimensions and assumptions. Member sizing, material capacity, loads, connections, field conditions and construction details are not evaluated. Independently review all dimensions, cuts, quantities and project requirements before purchasing materials or building. Ignotix — Rafter Geometry Studio.