Where is the best place to get 6 by 6 posts for my dock and what to I need to ask for?

I don't know about the best place, but Home Depot has them.

Boatman,

I just bought a 6x6 treated post at Home Depot. It was a 10 footer and it was 29 bucks. Make no mistake they are pretty pricey!! I would think Lowes would have them also.

I understand that treated posts come in different grades- ground contact, marine, etc. I want to get posts that will last under water and wasn't sure if just regualr posts from Lowes? HD would be OK. Anybody know??

I get most of my lumber from Menards. Their treated lumber prices can't be beat.
They carry 2 grades of 6 x 6 treated. One is only available in 8' and is primarily used for landscaping. It is lower cost, comparably, and carries a very limited warranty.
The other grade is the type you seek. It will have a sticker stapled to the end. It should show (something like) .6 pcf retention. We used this for our (freshwater) dock as submerged supports.
I don't recall the rundown, but when I was preparing to build the dock, all the research I gathered online pointed to .6 as an acceptable level of preservative retention for treated lumber submerged in freshwater.
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(edit) we also re-treated the cut ends

I'm glad we don't have those stores in California. In Home Depot here in California they often have greeters, do they at Menards?

There is a strong possibility that I would fall on the floor laughing if someone greeted me with "Welcome to Menards, can I help you find something?"


PS this may end up being a test of the "notify" button.

One time I got kicked in Menards.

I fell on the floor, but I wasn't laughing.

There's gotta be more to that story.

BTW, about 3 months I bought five 8 ft long 2x10's from Home Depot. They went on a picnic table. They were obviously unseasoned. Two of them have curled like a bow.

I'll be looking for something to make my dock out of soon. Are you just using the posts to secure a floating dock to the shore? I'm going to need something WAY longer than 10' because I want my dock to extend out into deeper water and I think I should sink the post in quite a few feet. How many feet should I sink the posts, I live in Michigan (anyone know?). On land we put posts in below the frost line or they heave up.

I have a Morton barn and they make posts by nailing staggered 2x6's together. They say this is much stronger and if you were to cut through the post you would see the wood treated thoughout whereas a regular post will be lacking in treatment in the center. Just another idea.

How big is your dock going to be? Is the 6 x 6 size recommended? Will a 4 x 6 work?

Well, I went to HD to look for some pressure treated 6 x 6's or 6 x 4's and they only carry .6 pcf. I was told that I should use .8 pcf, marine grade for fresh water. I haven't checked Lowes yet but I too would like to know where I can get marine grade pressure treated wood?