Groundhog says Spring is coming, need dock plans

[Pat Barry]

The dock at our lake cabin is old, rotting, and very heavy. Its also not long enough. I'd like to make it 24 to 30 ft long and have an L shaped final section with a bench. I've looked at the aluminum dock systems and they are a bit pricey for me. I'd like to build my own, probably with treated wood structure and cedar decking but I don't want to go with 8 foot long sections. That's what I have now and they are sooo heavy to pull in and out of the lake. I'd like to come up with a dock structure that could have an axle and a couple wheels attached so it could be rolled in and out with much less effort. I'm thinking of a treated structure with removable / modular decking. I think this would keep the total weight down and more manageable. I have the dock posts and hardware and would still use it to get everything level and stable. The L shaped section could be a separate part. Has anyone here built something like that and have an idea to share?

[Greg Cuetara]

Pat can't really answer most of your questions. 23'-30' long is pretty long and if you don't want to do 8' sections then maybe 6' sections. Also I question why you are using treated lumber. I think for areas where lumber may come in contact with moisture and then dry out treated lumber is good because it will not mold, mildew, or rot but if it is in constant contact with the water then it shouldn't be as much of a problem. Also typically with docks there is quite a breeze so the lumber will dry out quickly at least that on top. My grandfather built a dock about 16' long just out of regular 2x material about 20 years ago and maybe a year or two ago we rebuilt it because it was showing it's age. We just stayed with the same and use regular 2x material and after a few seasons it is holding up pretty well. If you go with either treated or regular 2x material as an undercarriage i think you would be hard pressed to get anything like you are talking about. I think one of the reasons the wheels etc. work is that the aluminum structure can span further and is much lighter so that the wheels will work. We now have 2 - 6' sections and one 8' section and they are a beast to work in and out of the water in the spring and fall but with 2 people it goes quite quick. The other thing is that if you don't have really even ground then a regular undercarriage can be wobbly. One thing the alum. structures have going for them is that their 'legs' go down to pads and you can very easily level the dock. They do make dock hardware where you can put the pipes down but that can get very expensive very quickly and is definately worth taking a second look at the premade structures. One other idea is that if you can make an under structure to support the walkway which is removable then you would be able to take that up to put the dock in and out and it would be much easier.

Good Luck,
Greg

[Pat Barry]

Greg - thanks for the feedback. I have the posts and pads and other hardware already each leg cost approx $50 - post, pad, bracket. I have enough posts for a 24 foot long dock now (3 - 8 ft sections). I was thinking of trying to make the structure out of 2x lumber, all connected together into one long section and have the wheels mounted near the end, maybe cantilevered a bit. Then use the posts and hardware to stabilize the whole thing. I will work on a sketchup of the idea and post it here. It might take a day or two. I'm not the fastest sketcher.

[Pat Barry]

Here is a very quick sketch
Dimensions are 24 ft long, 4 ft wide. 2 - 12 foot sections with 8 ft overlap (4 ft of each section). Dock posts would go every 8 ft. I threw on a couple wheels to get the idea across. There would be more cross-bracing of course. Thoughts??
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[Pat Barry]

Here is the dock with the planking attached. Not the most creative thing ever, I know.
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[Greg Cuetara]

Pat that looks like a typical dock that you can easily roll in and out. Again my biggest concern is the weight if you use 2x lumber as a structure. Also you will have to deal with trying to get a piece of lumber to span 24'. Not sure that I would want to break that up into two or three sections and bolt them together...

Have you tried to price out some pieces of alum on your own and maybe you can buy the structural pieces of alum to span the distance and then that will also keep the weight down when you pull it in and out. Again maybe think about building 4' sections of the actual walking surface and that would just press fit down into the frame that you build so that you can pull them out and the whole thing would be lighter to roll in and out. My FIL has something very similar but it is only about 15-20' long all alum with press fitted trex decking and he can pull that out when he takes the whole thing in and out and it makes it much easier. Another idea would be to add a set of wheels to the front so that you could hook the whole thing up to your car and truck and pull it out in the fall and then you can easily back it up in the spring time.

[Pat Barry]

Sorry about the delay in response on this. The two 12 foot sections are actually connected with one 8 foot piece of 2x material, each with a 4 fooot overlap to a 12 foot piece. The first picture shows that but maybe not so good. I thought this would basically extend the beam length on each side pretty efficiently so its not relying on just bolting together sections. Alltogether it will be one contiguous dock. An L shaped addition on the end would be a separate piece. I've calculated the entire weight of the frame assembly, including the 8 foot L addition to the picture as 380 pounds so weight is a huge issue. Taking off the 8 foot L drops the weight to 300 lbs. If I went with 2x6 instead ofd 2x8 the weight would go from 380 to 285 pounds. That might be worth looking at a little closer. For a dock, 2x6 might be plenty. Anyone have any thoughts on that?

I did intend the decking to be removable sections, 2 x 4 feet in size each.

I will have to do some looking for aluminum - not sure where to get that from?? I don't see Home Depot carrying that.