Building Homes or Extensions/slope


The front setback on a garage is 5791 mm (19 feet), and the slope from the top of garage slab to the sidewalk is to be 5%. The top of the 102 mm (4 inches) garage slab is located 203 mm (* inches) below the top of the foundation wall, at the front of the garage. What will be the depth of the buck, and what is to be the difference in height from the front sidewalk to the top of the garage foundation wall?

A. 203 mm (8")bucks and 289 mm (11 3/8") of height change
B. 203 mm (8")bucks and 492 mm (19 3/8") of height change
C. 305 mm (12") bucks and 289 mm (11 3/8") of height change
D. 305 mm (12") bucks and 492 mm (19 3/8") of height change

would you kindly explain why the correct answer is D, and explain how that answer was determined?
Thank you

Randy, I'm sorry but I have no reference to the term "buck".

If the sidewalk is at 0.00 and the grade is to be 5 percent traveling over 19'.  I see this as the math:

19' x 12"= 228"
228" x .05 = 11.4" (marvelously close to the ll 3/8 dimension)
+4 for foundation height = 15.4"

Is there a requirement for slope on the garage slab that could account for the additional 5"?  This would require an additional foundation height for the high end of the garage.

I see little or no other explanation.  I'm sorry but even Google does not recognize "bucK".  I know about door bucks and a few others.

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Dan Griffin


I can answer almost all questions related to the total construction process. My expertise is in commercial construction, though I can field most any residential question. I have hands on experience in concrete, heavy equipment, masonry, all phases of carpentry, interior finishes, and I am fairly strong in mechanical and electrical.


I have over 20 years experience as a commercial carpenter and commercial construction superintendent. I have another 20 years experience in facility management for a major school district.

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I hold a Bachelor's degree in English and Math. I have completed many continuing education hours in the building trades. I hold a Master Carpenter card from the AGC, Associated General Contractors.

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