How far should a deck post be in the ground?

Hereof, how deep do post holes need to be for a deck?

Footings typically must extend below the frost line to prevent shifting during freeze-thaw cycles. Dig footing holes about 6 inches deeper than required. Fill the bottom of the hole with 6 inches of gravel and compact the gravel with a 2x4 or wood post.

Beside above, why deck posts should not be set in concrete? A deck post should always be placed on top of footing, not inside concrete because it can break. When concrete is poured around a deck post in this way, the post will rot due to moisture buildup by the soil.

Likewise, should deck posts be in the ground?

There are several ways to set deck posts; we recommend attaching the posts to concrete footers above the ground. This helps to prevent wooden posts from rotting. Set footers a minimum of 6” below the frost line for your area to prevent movement during freezing temperatures.

Can you use 4x4 posts for a deck?

In the past, many decks were built with 4x4 support posts (also called structural posts). But these can bow seriously, even if a deck is only 3 feet off the ground. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them.