'97 UBC Fig. 18-I-1 Setback Dimensions

[rlflower]

As an engineer on the development end of things, my clients would like an answer to this question.

The term "H" in the aforementioned figure represents the overall height of the slope. "H/3" represents the required distance to daylight.

The question is how to define the term "H". If it is to be defined as the entire height of the slope - from the bottom of the creek bed to the top of the ridge - then the solution for "H/3" obviously becomes un-workable. However, if it is to be defined as the height between two points at which the slope levels off, then two questions arise: 1.) how level do these areas have to be, and 2.) how far should these "level" areas extend in order to be considered effective in determining the overall height?

Can you help me define this term? All comments appreciated.

-Richard L. Flower, P. E.

 

[PECPESC]

Is H/3 not the distance from the top of slope to the beginning of the foundation? Unless otherwise allowed by geotech?

 

[dirtsqueezer]

I believe 'H' in this case refers to the height of the slope itself. The building is what you want to protect, but I believe the actual slope is the main focus of that diagram. It sounds like you might want to recommend an actual geotech. If the river has potential to cut the base of the slope, you may have a situation that isn't covered by the 97 UBC.

Best of luck.

 

[ERV]

Just for the record. "H" is the vertical height of the slope. "H/3" is 1/3 the height of "H", which is the horizontal distance of the BOTTOM of the foundation to daylight, but need be no more than 40'. "H/2" is 1/2 the height of "H", which is the horizontal set back from the toe of the slope to the building, but need be no more than 15'.