Installing vinyl fence posts - how wide a hole should I dig?

Question

The post is 77" long and will be 36" in the ground. Some tell me 8" and some tell me 12".

The posts are 4x4. Plan to use concrete on ourside and peagravel on inside.

Am using power post hole digger.

Answer 1

36" is a deep hole. So going that deep I personally would choose the narrow or what ever is easier while digging. 36"s with a hand post hole digger might make the top of the hole pretty large when spreading the handles. Maybe rent a motorized unit but it requires two people to handle it. This would go a whole lot faster.

Answer 2

To be on the safe side you should dig the holes 12" square. This will give you 3" of concrete coverage around the post's. More concrete is better than less concrete!

Answer 3

8" should be plenty wide. That's about the width of a standard post-hole digger.
Still lots of room for concrete and / or gravel to go in too.

Answer 4

Assuming you will be using a std. posthole digger and the posts are 4X4 in. the the std. 8in digger will do the job. Will you be backfilling with dirt? or backfilling with concrete? either way be sure and use a level to insure a straight post.

Answer 5

Three times the width of the post.