Máximo de casas decimais: 4; Ao mais próximo; empates afastando-se de zero
Nota
50%
Roof pitch
6in 12
Ratio (rise : run)
1 : 2
Rise per unit of run
0.5
Rafter length factor
1.118034
Slope length
13.4164cm
This slope rises 0.5 for every 1 of run: 26.57° from horizontal, a 50 % grade, or a 6/12 roof pitch. Its sloped length is 13.4164 cm.
Slope profile, to scale
Como é calculado S
Slope
m=runrise=126=0.5
Ângulo
θ=arctanm=arctan0.5=26.565051∘
Grade and pitch
grade=100m=50%,pitch=12m=6 in 12
Rafter factor
1+m2=1+0.52=1.118034
Multiply a horizontal run by this to get the sloped length.
Slope length
rise2+run2=12×1.118034=13.416408cm
Sobre Inclinação do telhado: ângulo, porcentagem e desnível
Every way of stating a slope comes from one ratio, m = rise ÷ run. The angle from horizontal is arctan m, the percent grade is 100m, the roof pitch is 12m (units of rise per 12 of run), and the rafter factor √(1 + m²) turns a horizontal run into the sloped length. Enter a rise and run, or any one of the other forms, and the rest follow.
The default rise of 6 over a run of 12 is a 6/12 roof: 26.57°, a 50% grade and a rafter factor of 1.1180, so 12 cm of run needs 13.4164 cm of rafter. Ramps and roads use the same numbers: the steepest ramp the 2010 ADA Standards allow, 1:12, is an 8.33% grade, or 4.76°.
Percent grade is not an angle: a 100% grade is 45°, and a vertical face has no finite grade or pitch, so angles must lie between −90° and 90°. A negative rise describes a downhill slope.
Fonte de verificação: Python 3.8 math: degrees(atan(4/12)), sqrt(1 + 1/9)
Perguntas
How do you convert percent grade to degrees?
Take the arctangent of the grade divided by 100: θ = arctan(grade/100). An 8% road grade is arctan 0.08 = 4.57°, and a 100% grade is 45°, not 90°. The reverse is grade = 100 × tan θ, so a 30° slope is a 57.7% grade.
What angle is a 6/12 roof pitch?
26.57°. A pitch of x/12 means x units of rise for every 12 of run, so the angle is arctan(x/12): 4/12 is 18.43°, 6/12 is 26.57°, 8/12 is 33.69° and 12/12 is 45°. The rafter factor for 6/12 is √1.25 = 1.118, so 12 ft of horizontal run needs 13.42 ft of rafter before any overhang.
What is the maximum slope for a wheelchair ramp?
1:12 under the 2010 ADA Standards for Accessible Design (§405.2): one unit of rise for every 12 of run, an 8.33% grade or 4.76°. Each ramp run may rise at most 30 in (§405.6), so a 30 in rise needs a run of at least 30 ft. Other countries set their own limits in their building codes.
How do you calculate rise over run?
Divide the vertical rise by the horizontal run, both in the same unit: m = rise/run. A roof that rises 6 in over 12 in of run has m = 0.5. Measure the run horizontally, not along the surface: the sloped length here is 13.42 in, and dividing by it gives 0.447, the sine of the angle rather than the slope.
Qual é a precisão de “Inclinação do telhado: ângulo, porcentagem e desnível”?
A precisão depende dos dados inseridos e das hipóteses do método. O cálculo decimal usa 50 algarismos significativos, mas estimativas, métodos numéricos e dados de origem podem ter menor precisão; o arredondamento exibido não elimina essas limitações. Exemplos resolvidos verificados com fontes independentes: 8. Por exemplo, “Rise 6, run 12 (a 6/12 roof)” é verificado com Python 3.8 math: degrees(atan(0.5)), sqrt(1.25), sqrt(6**2 + 12**2).
De onde vem o método?
OpenStax College Algebra 2e, §4.1 — slope as rise over run; US Access Board, ADA Standards §405.2 — ramp slope 1:12 (8.33 %).
Sobre esta calculadora
m=runrise,θ=arctanm,grade=100m%pitch=12m in 12,factor=1+m2
Esta calculadora inclui 8 exemplos resolvidos com respostas de fontes independentes. Eles fazem parte do conjunto de testes e você também pode executá-los aqui.