Questionim a landscape contractor I have built many walls, but they were in clay not sand, ive always used crushed rock as my base and pea gravel behind 4 drainage. the walls i might build r approximately 80ft long by 4ft tall, 2 walls one will stagger 3ft or so behind the low wall, and they want stairs going through the middle of both walls. do i need to pour footings so deep with rebar. im afraid of them settling. I give a one year warranty. I only do jobs if they can get done right. Thanks! shaun
AnswerI would have a geotechnical engineer do a soils test in a few places along your footing unless its all the same, then one representative test should be fine. You need 3000 psi soil bearing capacity. Sand is usually ok of it is well compacted. Soils test should be several hundred dollars. If you don't have suitable soils ask them to make a recomendation for what to do. Typically you remove the unsuitable soils or make a wider footing. You may have to get an engineer involved. expect a $500 or greater fee for this. My engineers charge about $1500 to do a detail for a short wall and stanp the drawings.
Best of luck
Sean Murphy, LA, ISA, LEED AP
www.seanjmurphy.com
