Florida Fence Posts

Doubts in S. Florida · 2016-04-06T16:44:02+00:00

Building a 6' tall horizontal fence with 4x4 PT posts and a combination of horizontal 1x6 and 1x4 PT members (with 3/4" gap between boards). Florida building code calls for 4' spacing of posts and 24" depth with concrete footers. I would like to skip the concrete and use pea gravel to avoid future rotting. I also don't want the extra expense of transporting and pouring concrete (even if I pour it dry and let groundwater cure it). I already placed the order for 8' fence posts (buried 24" in gravel), but am wondering if I should buy 10' posts and bury 4' in gravel. I have an auger with extensions, so hole depth isn't an issue. Soil is very sandy in Florida and area where posts go is elevated, but bordering a rainwater drainage ditch. The ditch only fills after very heavy rains and will drain from sandy soil in about 1 day. My 2 questions are: 1. For a 6' fence, 10' 4x4 or 8' 4x4? Pea gravel packed. 2. For 4x4 posts, should I use a 6" auger bit or 4" auger bit? Thanks