Expert: Bruce E. Johnson - 3/23/2009

Question
Do you need concrete piers under a concrete patio. We are having a new front patio installed. The old walkway is removed, the front stoop is being left under the new patio(was poured with foundation, is 3x9). We are in San Antonio, Tx , so have little to no hard freezes. Recent drought and then heavy rains are causing lots of foundation problems. We want the new walkways and patio to "stay put". Contractor is using rebar to attach to front of house, wire mesh throughout. Have had too many comments from friends and websites to really KNOW whether I should get support piers under patio area of aprx. 10x20 that will be an extension of the front walkway. HELP....

Answer
Hi Mark, if it is just a patio?  Then I see no need for piers.  I like to do a thickened edge of 8" deep by 8" wide to help keep any erosion to a minimum but most patios are just 4" thick slabs with wire mesh..I hope this information helps feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com