@Anonymous
Slope of the ramp is a ratio... It rises a height X every L distance traveled
As per standards and regulation, ramps are not only defined by their slope; but also how long do they ravel (considering that one might be on a wheel chair and might not be able to role him/her wheelchair up a 200' ramp...That is what you set in the type properties of that ramp -
- the Maximum Length of the incline
- the Maximum Slope
If you are doing a pedestrian ramp to ADA standards (That is what your Revit book or better say Eric Wing assumes in their example)...The Max Length cannot exceed 30' 0" and the max slope cannot exceed 1/12
THEREFORE before USER (ex: you) set those values; the user need to
- figure out where the ramp will start and where will it end - ie: On the properties Pallet Set the Base Level and the Top level of the Ramp (ie: total rise/height) - In your case that would be
- Base Level: Level 1
- Base Offset: -2' 6"
- Top Level : Level 1
- Top Offset: 0
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- Then user decides how long he/she desires this ramp to be...ie The Incline Length - (In your case 30') - ADA standard)
- And the SLOPE RATIO which is simply Height/Length ... (in your case you will leave it at 1/12)
It's simple trigonometry and right triangle formulas
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That book or it's author has a Youtube channel I think or website where he has videos of all his chapters...maybe it would help you better if you search for it...
Well or wait for your best friend from Autodesk