Wood frame pond

[Whitr9870]

Hey guys. Not new to ponds, but new to raised wood ponds. Im in the middle of making the frame for the pond. Frame is 3x2 timber, which will be lined inside with plywood. What im wondering is the plywood is 9mm thick, would this be ok for the base, would it take the weight.
Internal size of pond is 6ft long, 2.5ft wide and 2ft deep.
Pics attached

 

[Lisak1]

Welcome! We have a few members with raised wood ponds. @Sparky may chime in here.

 

[Jhn]

I would add one more 2x in each space on the bottom, so there would only be 9” between each one to support the plywood bottom.

 

[qclabrat]

Welcome, seems like raised ponds are quite the fashion on the other side
We have a number of UK ponders here and hope someone chimes in soon.

 

[Panzer13]

Hey guys. Not new to ponds, but new to raised wood ponds. Im in the middle of making the frame for the pond. Frame is 3x2 timber, which will be lined inside with plywood. What im wondering is the plywood is 9mm thick, would this be ok for the base, would it take the weight.
Internal size of pond is 6ft long, 2.5ft wide and 2ft deep.
Pics attached

Welcome to the forum.
I have a raised wood framed pond. I calculate that is about 225 gallons, which weighs 1876 pounds. I am afraid your 9mm plywood wood not hold the weight. I would put twice the supports underneath the plywood and double the thick ess of the plywood to 18mm.
Question is any of that lumber rated for ground contact? If no then you will need to put something on the bottom that is. If you don't lumber will forever it meets the ground.
I built my pond out of pressur treated lumber. I put steal straps length wise every 18 inches. Also put cross supports across the top in places.

 

[Sparky]

Hey guys. Not new to ponds, but new to raised wood ponds. Im in the middle of making the frame for the pond. Frame is 3x2 timber, which will be lined inside with plywood. What im wondering is the plywood is 9mm thick, would this be ok for the base, would it take the weight.
Internal size of pond is 6ft long, 2.5ft wide and 2ft deep.
Pics attached

Since your framing is complete I believe you are going to need to seal that wood as it does not appear to be pressure treated. Minimum 1/2” green treated ply on the inner skin. Also critical, is your frame screwed and glued? The strapping panzer mentioned will be a must if not. Keep us updated. Take a look at my pond. There’s some construction phase pics. Hey, welcome!

 

[ShawnInfirmity]

I agree with @Panzer13 and @Sparky about using treated plywood for your base or anything that will come into contact with the ground. For my above ground pond my base was made out of 3/4 inch treated plywood and I built the sides out of treated landscape timbers and finished the inside off with 1/2 inch (untreated) plywood sheets.

 

[Jhn]

Treated lumber of any type from big box stores isn’t rated for ground contact. Sitting on cement is fine, but in the dirt it will rot just as fast as untreated lumber.

You can’t get ground contact lumber anymore at all in anything 2” and wholesalers won’t sell the ground contact rated material in heavier lumber to regular homeowners.

 

[mrsclem]

We have 2 ponds built partial above and below ground. Both built from 2x12 pressure treated lumber. Have not had any problems with the wood rotting but using a smaller size lumber, I would be concerned. Maybe treat it with a waterproofing first.

 

[Whitr9870]

Right guys thanks for all your replys and tips. Just so you know all would will be treated after its done and before any liner goes in. I have doubled the ply on the base so it is now 18mm. I have purchased new 20mm and done all the sides with that. I have added extra support beams in the base also. So hopefully that should be enough?
The whole thing will be sitting on concrete base raised about an inch or 2 off the floor aswell

 

[Whitr9870]

Btw this is only meant to last a year, 2 tops untill i get the go ahead to do my in ground one which will be in the range of 10x8 x4-5 foot deep.

 

[mrsclem]

Sounds like a good plan!

 

[ShawnInfirmity]

@Whitr9870 Are you going to do the in-ground pond in the same spot or might you be able to keep both eventually? I know I wouldn't mind having more than one pond... LOL

 

[Panzer13]

Right guys thanks for all your replys and tips. Just so you know all would will be treated after its done and before any liner goes in. I have doubled the ply on the base so it is now 18mm. I have purchased new 20mm and done all the sides with that. I have added extra support beams in the base also. So hopefully that should be enough?
The whole thing will be sitting on concrete base raised about an inch or 2 off the floor aswell

Sounds like a good plan. Keep us posted, look forward to seeing pics of the project. Cheers!

 

[Sparky]

On the right track! Keep us posted.