Rafter Tools+ for iPhone Main Screen Usage

Roof Eave Angle

This is the corner angle of the building. Most Roof Eave Angle corners are at 90°. For Octagon Roofs and 45° Bay Window Roofs use an Roof Eave Angle of 135°. For Hexagons Roofs use an Roof Eave Angle of 120°.
For irregular or bastard hip roofs the Roof Eave Angle can be betwen 10° and 170° You'll get an Unconstructable error message if the roof is unconstructable with the current input parameters.

Main Principal Rafter Slope Angle or Pitch

Select the input type from the input menu, Imperial/English Inch base 12 —— default, enter roof pitches from 1—24
like 8 for an 8:12 pitched roof, Metric 300mm base, enter millimeters like 200 for a 33.69007° roof pitch angle,
Decimal Inch base 10 —— enter base 10 decimal numbers like 5.7735 for a 30° roof pitch angle,
Degrees input —— use any roof angle in degrees like 33.69007°

Adjacent Rafter Slope Angle or Pitch

Select the input type from the input menu, Imperial/English Inch base 12 —— default, enter roof pitches from 1—24
like 8 for an 8:12 pitched roof, Metric 300mm base, enter millimeters like 200 for a 33.69007° roof pitch angle,
Decimal Inch base 10 —— enter base 10 decimal numbers like 5.7735 for a 30° roof pitch angle,
Degrees input —— use any roof angle in degrees like 33.69007° Use equal rafter slope angles for Octagons, Hexagons or other types of polygonal roofs.

The input mode selection

- Input Menu Mode
- Imperial/English Inch base 12 —— default.. use American standard pitches over 12.
- Metric 300mm base —— 300mm is 11.81102 inches, similar usage to the American framing squares printed in inches.
- Decimal Inch base 10 —— use this option when working with tangents or using the Chappell Master Framing Square multiply the tangent of the angle by 10
- Degrees

The output Menu Mode selection is used for the hip rafter width. The calculated lengths will also use the inch,metric and decimal inch for calculated rafter lengths and dimensions.

- Menu Selections
**in**Imperial/English Inch base 12, default.. uses American standard fractions of an inch.**mm**Metric mm base.**dec**Decimal Inch use this option when using displaying the calculated lengths in decimal inch.

The calculated results will display the Eave Angle used for the calculations. As well as the Main Roof Slope Angle, Adjacent Roof Slope Angle, Main plan Angle and Adjacent Plan Angle.

Select **"in"** for results displayed in fractions of an inch. Select **"mm"** for millimeters or **"dec"** for decimal fractions.

Select the type of input for the roof pitch/slope. The default is Imperial/English Inch base 12, enter the rise of the roof rafters like 8 for an 8/12 pitched roof.
Metric 300mm base, enter 200 for an 33.69007 roof slope angle. Enter 6.666 for an 8/12 when using base 10 or select degrees for the input type for decimal fractions for roof slope angle like 35.00°.

The calculated results will display the Hip Rafter Layout Angles and Dimension for the foot of the Hip Rafter.

The calculated results will display the Hip Rafter Layout Angles and Dimension for the peak of the Hip Rafter.

The calculated results will display the Hip Rafter Layout Angles and Dimension for Square Tail Fascia at the tail of the Hip Rafter.

Click on the **"Timber Framing Angles"** to display a list of the Timber Framing and HawkinDale Angles for the roof.

You can select different display formats for the Timber Framing angles.

"Degrees" "Base 10" "Base 12 decimal" "Base 12 fractions" "Tangent" "90° - Angle" "90° + Angle" "180° - Angle" "180° + Angle"

You can click on any of the Timber Framing Angles to display an help file with the description of the angle as well as the Hip-Valley Roof Trigonometric Angle Formulas.

On the main screen you can click on the **"Lengths"** button to display a calculator for entering the dimensions for the roof.

Main Side Rafter Run Ridge Width Rafter Material Depth Rafter Seat Cut Length Main Side Rafter Overhang RunSelect either the "Unequal" or "Equal" button for the type of overhang calculations.The "Equal" overhang calculation will calculate the offset run from the corner for the hip rafter as well as the plate height difference for the equal overhang runs.

On the main screen you can click on the **"Jacks"** button to display a calculator for entering the jack rafter spacing.

Jack Rafter Spacing Jack Rafter Material Thickness Special Jack Rafter Plate Line Run

On the main screen you can click on the **"Hip Angles"** button to display a list of the hip rafter angles for the roof. Click on any of the angles and a popup dialog box will display the framing square usage for the angle.

On the main screen you can click on the **"i"** button to display this help file.