Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Building a new Dock

Hey guys, I am building a new dock in existing water. I was wondering what your ideas were for placing posts in the water. I am only going to be dealing with 2-3 foot of water and I have a tractor with an auger to dig my holes. The ground is pretty hard clay after the one foot of muck and does also contain gravel. My question is , what is the best way to anchor in the posts? I thought of using quickcrete ,but I was unsure of how to do it when the holes will be in the water. I also thought about just adding gravel and tamping it down. I have done the gravel thing with 20ft telephone poles and it held them up. The very front posts are the only ones I have to worry about dealing with water as my pond level is down enough I can easily concrete the others in. It is going to be around 16 x 25 ft. Any advice would be appreciated. Thank you, John

No problem with concrete curing under water. It is much heavier than water, and will settle around the posts and compact itself. As long as the posts are secured and don't move during cure, the concrete will be as strong or stronger than air cured concrete.

For what you're doing pouring underwater will probably be fine but will be weaker than if poured above ground. Wet concrete can become overhydrated. If you've ever seen the surface of concrete chipping off, it is likely that the person finishing it sprinkled some water on top to speed the process. The upper 1/4" or so becomes weaker and therefore chips off easily.

Are you trying to pour a footer for underneath the post or simply around to post?

Fast setting mix would probably be better than regular mix.

I put a steel plate with a 2.5' pin on the bottom for my "footers". It serves the same purpose as setting the post on a concrete pad. If you're using wood posts, a pin could be welded to the top of a plate and a hole drilled in the bottom of the post then the post could be slid over it.

Yet another option is to drive a tube into the clay then pump the water and muck out and then place your concrete, again fast setting would probably be a good idea.

I am just using it to pour around the post to hold it in place. Did anyone have any thoughts on using gravel and tamping it in? Thanks guys

If it's all contained in a hole, you don't have to tamp pea gravel.

get a concrete form from home depot that will slip over the post, pour it full of concrete. they come in diff. sizes. 1 should do, saw it in half.

Hey JK...
Let's get outta this box, eh?
-
What if....
You set the pier on permanent concrete footers in the shallows that are accessible by equipment. Then, build a hinged section that attaches to the end of the last permanent section. Attach the other end of this hinged dock section (with another set of hinges) to a floating dock. It will always be at the perfect height. The drawback will be if/when you get a hard freeze. I don't know how much abuse the various floatation units will take, let alone the shear of moving ice floes.

Check out the muck pad and auger foot on this page
http://secure.tommydocks.com/index.cfm/choice/quarter_accessories/page/intro

The ones I made for my dock were a sort of hybrid between the two.

Ok, I am either going to be using a 6x8 post or telephone poles because I have them already. Those all sound like great ideas and I will let you know what I do when the time comes ( this week hopefully) anyways I have another question for you guys. I was wondering if I could use 1x6 or 1x8 oak lumber on the deck. From what I know oak is pretty strong and is already rot resistant I think ? The reason I ask is I can get about 100 of these for 150.00 dollars. I am looking to go cheap ,but still have something strong that will last. I am looking at a 16x20 to 25 foot dock. If I can use these how many inches apart should my joists be underneath which will be at least 2x6 if not 2x8. Please help soon because those materials may be gone soon. Thank you again, John

Oh by the way the boards are 8 foot in length. Thanks

I think 16" o/c would be fine for oak planks. 16" o/c for treated pine 1-1/4" works and oak is a lot stronger. I've never seen it done but I'd bet they'd last quite a while considering how long oak barn siding lasts. If they were sealed regularly I'd bet oak would outlast unsealed treated. At that price I'd use the oak.

I must admit that I have never considered oak for an exterior application. It just never came up as a consideration....maybe cuz of it's normal expense over other options. This is interesting. Does anybody have personal experience with oak in an exterior application like decking?

I would make the joist's 8 foot long and then they would tie into a 16 footer going the opposite direction across the center. I could stagger the joists on either side of the 16 footer if you thought this would make it stronger.

This is from brettski in a PM

2 x 6 joist span of 96" is fine. The 16 footer is going to be bearing alot of weight. I would seriously consider a double 2 x 10 (or even a double 2 x 12 ???) beam to span the 16'. Think about the header over a 16' garage door; usually a double 2 x 12.

Brettski

What did you mean by pallet stock?

In 1974 I built a 18' x 36' deck with untreated, freshly cut red and white oak. Bought it directly from the saw mill.

The deck is still standing today.

HOWEVER, fresh cut oak shrinks terribly. I placed the 2x8 planks tightly against each other and I still had 1/4 inch gaps. Also, any piece that was not securely nailed or screwed to something twisted and bowed terribly. We put a 2 x 8 top rail on the top and where we made a 45 degree cut in each plank to form a corner the shrinkage between the two pieces was so great that we had to take off the entire rail cap and replace it with western cedar.

It also gets harder and harder to work with each day, especially if the weather is hot and dry. This is because the moisture leaves it rapidly.

On day one nails were easy to drive, on day 17, when we finished we had to drill holes in order to drive the nails.

You may not be talking about green lumber, but if you are beware.

Bing

No, it is not green lumber. Thank you

I have used white oak for cattle catch pens and for flooring on equipment trailers. It is preferable in these uses because it takes a pounding and distributes weight better than pine boards. Seems like it lasts @ 10 yrs or so on catch pens untreated. It is VERY hard to nail and sometimes subject to split. Hard, high quality screws would be the way to go. Don't skimp on the wood treatment afterward. I have had good luck with oil based. Your spacing should be the same though as if you were using pine boards.

So, I assume then that the whole frame should be at least 2x10 with a double in the center. I could then use 2x6 joists to screw the decking to correct?

Honeyhole- Bing

Thank you for your replies. I think you guy's have made me decide to do this with the oak. I still haven't been able to get a hold of the guy ,but when I do I will let you guy's no if I get it and what he says about the wood. Brettski said something about the fact that it might be pallet stock. I have no idea what that is. Thanks guys

Pallet stock is the bottom of the barrel quality oak. It's what they use to build skids.

Ok , Thanks

I still have no answer on his phone. Will let you know what kind of wood he says it is.

White oak would be fine. I am probably going to be building mine out of the same stuff along the lines of Brettski's floating dock idea, I have a small sawmill and lots of oaks. Red oak has open pores and may not weather as well, water can get into it easier. Oak does lift a lot more splinters than treated pine, so it may not be very good if you like to take your shoes off. Any green wood will shrink so plan for your gaps, they are only going to get bigger.

Ok guys, I finally got a hold of the guy with the oak and he stated it was rough cut he thinks. He said he gets it from an auction house and that the wood is cut straight and the right lengths ,but would need sanding or something to smooth the boards for walking on barefoot. Is all oak rough like this or is this probably pallet wood?

Oh yeah, is anyone familiar with galvenized grain bin flooring.There is a guy selling it for 5.00 for 12 to 20 foot sections. He advertised that it was good for trailer and dock flooring. I just can't picture what it looks like. Thanks