garden pond out of sleepers

[gizmo]

hi i have been trying to make a wildlife pond for our garden , first i tried to have a inground pond but soon found out i could not dig down more than 10 inch due to compressed chalk , so our pond is in ground and raised up with sleepers and is 6 foot x 5 foot x 30 inch deep now at the moment my problem is shelves and the underlay / liner ,
it was said about having shelves made out of sleepers inside of the pond which i suppose is a good idea but with the underlay / liner how would you stop it from tearing etc , i got my underlay etc from swell online and it is 6mx6m approx 20 foot square , should i use a different underlay / liner for a pond made out of sleepers as i am finding it hard / impossible to put it in our pond .. so at the moment unsure what to do thanks for any advice

 

[poconojoe]

"Sleepers", to me, is too general of a term. I'm assuming you are describing some form of timbers. Please describe exactly what you intend on using.

You don't mention the type or thickness of underlayment.

Not knowing what your "sleepers" are made of, their dimensions, or the type of underlayment you are referring to, I'll take a shot...

I don't think it's necessary, but if your sleepers are large timbers, you can round off the sharp edges where they contact the underlayment and liner. Use a double layer of underlayment around that area if you feel the need.

You should be using an EPDM 45 mil. liner. Do not use a PVC liner. EPDM is a thick rubber material.
You can buy the non-woven underlayment along with the liner. Since you are concerned, I believe they make a thicker version of underlayment you may want to go with.

 

[poconojoe]

Also, looking at your picture, I hope you secured the corners well to prevent the water pressure from blowing them out. A lot of people drill down through the wood, then hammer rebar down through them deep into the ground.

 

[gizmo]

Thanks for your reply each sleeper is 6 x 4 inch. And made from wood. When I got the liner it came with free underlay but had a awful job putting it in
The timber is put together using torx screws 6 and 8 inch long. All the bottom corners. Are fixed to the ground with 1 foot plates fixed to the corner of the bottom timber. When using underlay how do you fix it inside a timber build pond
Thanks

 

[poconojoe]

If you're having trouble keeping the underlayment affixed to the vertical wall, maybe apply some type of adhesive to hold it there until you install the liner.
Maybe use PL-S30 or standard silicone caulk. Let it cure a day, then install your liner. You don't need to completely spread the adhesive, just use it where it's needed to hold it in place. Maybe the top area and in the corners.
I wouldn't use anything like staples, nails or screws which may puncture the liner.

You might want to lay your liner over that top decking material, then add another layer of decking to cap it off. Don't do that until the weight of the water has fully settled the liner. You don't want to secure the liner, then have the weight of the water stretch it.

 

[gizmo]

Thanks for the reply. With the pond there are no shelves untill approx 20 inch down from top of timber sleeper. Would it be a idea to put in shelves made from timber sleepers but how would underlay / liner go around the shelf without tearing. As the pond is 6 x 5 foot 30 inch deep I looked at a pond. Calculator and it. Said I would need 14 x 13.5 foot of liner etc. If shelves. Are put in would I need. A bigger undrrlay / liner

 

[GBBUDD]

What you'll want to do is to have the underlayment come up the sides of the sleepers. And drape over the top . Beware the standard edge has the ability to be to sharp and can cut through the underlayment and liner a quick rounding over of the corner will solve that. You can secure the liner with roofing nails or a piece of wood to hold tge liner or even just some staples untill you get another piece of wood on top of what you have now like a 2x10 and you can dress that up. One note if there's any chance of the bottom sagging under the weight or the liner getting stretched you'll want to leave some slack so the liner has extra and does not tear.

 

[poconojoe]

What you'll want to do is to have the underlayment come up the sides of the sleepers. And drape over the top . Beware the standard edge has the ability to be to sharp and can cut through the underlayment and liner a quick rounding over of the corner will solve that. You can secure the liner with roofing nails or a piece of wood to hold tge liner or even just some staples untill you get another piece of wood on top of what you have now like a 2x10 and you can dress that up. One note if there's any chance of the bottom sagging under the weight or the liner getting stretched you'll want to leave some slack so the liner has extra and does not tear.

I wouldn't permanently secure the liner until the pond has settled with the weight of water.

 

[gizmo]

Thanks for the reply. When I was looking for a liner I looked on a site called amazon it showed a liner with free underlay from swell so I bought a 6mx6m the item said it had I think 25 or 40 year life span.
When trying to put underlay in was very hard for me to do and not sure if the underlay is pvc or not.
Can you please advise on what make of underlay to use with the idea of glue to stick it with and would the underlay come in 1 piece or several. I think that this is my problem as the underlay is all in 1 and 20 x 20 foot as I have no one to help putting it in thanks