> For the complete documentation index, see [llms.txt](https://docs.archlogbook.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.archlogbook.co/02-urban-site-planning-building-design-concepts/slope-gradients.md).

# Slope Gradients

**Slope gradient represents how steep a ramp is.**\
**It is represented by a ratio of rise to run.**

Or its height and length respectively.

The smaller the unit of run vs 1 unit of rise, the steeper the slope is.

Thus a 1:8.3 slope is steeper than a 1:15 one.

## **Common gradients:**

**(slope gradient listed are the maximum allowed and are non-exhaustive)**

1 : 2 - Steepest slope for earth without need for ERSS\*

1 : 8.3  - Steepest vehicular access slope

1 : 10 - Equipment ramp

1 : 12 - Wheelchair ramp

1 : 15 - Fire Engine deployment, heavy vehicles straight ramp

1 : 20 - Curved ramps for heavy/articulated vehicles (20/40ft trailers)

1 : 25 - Handicap Ramp without need for handrails

1 : 30 - Drainage gradient for public roads

1 : 100 - Screed to fall for roof drainage

1: 200 - Screed to fall for workshops drainage