We're planning on having a 1000 ft2 flagstone patio installed. We
have received estimates for both a dry install with rock/stone(?) dust
and a mortored install. What are the pros and cons of each. We live
in Northern Virginia by Washington DC. We do have a large, mature
sugar maple that will be approximately 6 feet from one corner of the
patio. Our concerns are these roots and heave. We want a very flat
surface which leads us to mortored, but are afraid of cracking in the
cement due to the roots. We believe that we can repair any root
movement in a dry install, but worry about the overall flatness over a
period of time. Thoughts?