Thread: Treated Pine for retaining walls

Most of my retaining walls are 200x50 T/P sleepers. But the highest I've gone with them is 500mm. I have just used the same stuff for the posts, set in concrete. 800mm is getting on to the high side (I think the highest you can go without engineered design is 900mm) but I guess you'll be OK if it's only a small section that high. I'd just make sure the posts are well into the ground and have plenty of concrete around them. For the short walls here, I've only gone in 300mm, but I reckon for an 800 high wall, I'd be trying for at least 600, if not 800 and a 400 sq. footing.

BTW don't expect this stuff to stay nice and straight. It warps like you wouldn't believe after a few days in the sun. It doesn't bother me, because I like the rustic look. But if you want it to stay straight, then you'd be better looking at hardwood.

mmm... I'm looking for that straight finish, but then again i don't want to spend too much on it.... a bit of warping is ok in my books.

The 800mm high wall is the highest and wont be taking much weight at all, was planning on going double into the ground for this one so 800 in the ground.

Is there much of a difference between TP and Ironwood?

I'll go and click some photos of a work in progress.

Can't help with the ironwood, never used it.

The walls under the established gardens have been in place for about 2 years. The rest I started on late last year. They were all nice and straight when I put them in.

I bought these in packs of 24 * 2.4m lengths for about $11 each.

That is exactley the type of thing i'll be doing.... they are really only going to be 3-4 lengths high, depending, as I step then down the slope.... essentially 3 levels, the first being 800odd high, the second should only be 400odd high and the third will only be 200odd high....

I am thinking of capping the wall aswell with sleepers aswell to neaten it up a bit.

Appreciate the photos and your help!!! I'm sure things will be done by tomorrow afternoon, aslong as this weather holds off

Yes I plan to put a cap on the wall up near the house to finish it off. But I'll probably use some 120x38 or similar for that. I've got a railing to put in as well which will be of the same stuff. It runs along the top of the wall in pic 4 where you can see the 90x90 post. That's to stop the missus falling backwards off it when she's hanging out the washing!

The first set of walls we put in, I only put posts at the joins - so every 2.4. This is OK in that situation because it's not really seen down where it is. For the walls that are seen, I've put in posts every 1.2m. I'd recommend you do that because a) it makes the wall stronger and b) seems to help with the warping.

I use 100mm hex head galvanised screws to join them. Some people use bolts, which are probably better going into pine, but the screws are so quick.

When the whole job is finished, I think I will hit it all with the Karcher and put a couple of coats of decking oil on.

I'm praying for fine weather tomorrow too because I've borrowed my neighbour's bob cat and I want to get that area where the blue tarp is finished off and ready for paving.

Remember to store them in the shed on a flat floor before use

Yeah, not in a stack outside like I did

No worries, they'll be sitting in the garage on the ground... but I plan to take the ute and get them in the morning and have them all in the ground by the afternoon!! That is, I plan to... bloody weather around here lately will determine that tomorrow.... either working in the yard, or beers at a mates place....

Hmmm, those photos you see up there represent several weekend's work and it's probably not even half finished. But then it takes about half an hour to dig one post hole in the concrete that passes for dirt under my place...

Good luck with it.

Oh and one other tip, wherever I've made a cut, I've painted it with a sealer. You can get green stuff designed for the purpose, I just used that black Ormonoid waterproof paint. I don't know if it's really necessary, some people say it is, but it can't hurt.

yeh, the earth that i'm working with is fairly hard, but soft enough... helps having a few mates around, and a couple of post hole diggers and bags of rapid set

All things well, tomorrow afternoon seems do-able... but realistically Sunday...

Thanks again for the help, cheers

Silent you shoud have shares in Koppers Logs with that much treated pine round mate!

Just call me Mr Kopper

It's good stuff for me to work with. I'm set up for it and it's easy to do on your own. Nice and quick compared to blocks and way cheaper.

I've used about 30 sleepers so far. Still got a bit to do yet.

At $11 Each, very cheap & effective.... I prefer the sleeper wall over block wall if its in the garden.... Looks much nicer IMO