Question
Hi Marc,
I am currently a student and was approached to do some work for an elderly lady.  She wants me to raise and level the paving stones in her driveway as they have sunken overtime because of the weight of cars moving over them.  I have lifted some of the stones and there looks to be a sandy, small gravel underneath.  I have stones dust and some hardening sweeping sand.  How much should I use/ what should I do?  Any ideas?  Thanks a tonne!

-Matt

Answer
Don't use crusher fines/stone dust, as the particles are not uniform, and this is probably what caused the problem in the first place.

(http://www.brownsconcrete.com/paving_questions.htm)

Use a uniform, screened sand, like masonry sand, that will have less settlement over time.  The hardening sand goes on LAST, after the repairs are completed. The bag should have instructions, if it goes on dry or wet pavers, or if you have to power-wash thge pavers before application... Some go on differently.  It is supposed to knit the joints together.

You'll want to lift the old pavers that are sunken into rutts, add the masonry sand, compact with a hand compactor (so remove enough pavers to get the compacter IN to do the job), replace the pavers, being careful to not add an extra lip at the transition between old and new work, then add the hardening sand as the last step, per manufacturer's recommendation.

Good luck ~Marc