Expert: Bruce E. Johnson - 4/15/2009

Question
I am putting in a 8 foot by 20 foot patio in from of my house and was
wondering what I would be looking at for prices on the gravel and sand needed
to install a dry set patio, I already have the pavers I am using.  Thank you very
much.

Answer
Hi Brendan,  I'm not sure what gravel or sand goes for in your area but a quick call to a local fill dirt supplier should answer that question.  I can give you the yardage.  When figuring concrete, sand, or gravel you basically multiply length x width x thickness in feet, this will give you the cubic feet.  27 cubic feet make up a yard.  So the formula I used to come up with your fill requirements is as follows:
8'x20'= 160 sq ft.,  160 sq. ft. x .33 (4" is .33 of one foot)= 52.8 cubic feet..there are 27 cubic feet in a yard so.. 52.8 / 27 = 1.96 cubic yards.

Where I live we don't normally use gravel, just 4" of compacted sand over compacted sub soil.  But if you insist on a sub base of 4" of gravel then you will need 2 yards of gravel, and top that with 2 yards of sand.  Because you will be compacting the material you will lose 25% more or less  so in your case I would order 2 cubic yards of gravel and 2 1/2 yards of sand..

I hope this information helps feel free to write again regarding this or other matters, sincerely, bruce e johnson..bejohnsonconsulting.com