Restore or replace timber retaining wall?

[DIYDean]

Hi Team,

We have recently purchased our property and finding heaps of things that need fixing..... (joys of owning a home I suppose). I have taken down a few tons of golden cane palm trees to allow light into the house and want to start over and replace the trees with a hedge. However, I am now looking at my retaining wall (fully exposed from trees in possible 15 years) and wondering if it needs restoration or replacing before I put my hedge in. I am inexperienced so any feedback on this would be awesome. Although I would definitely like to do something to prevent additional work in the near future that would require me to restart any work on hedges etc.

My main concern is the structural integrity of the timber. While most of it appears to me to be in okay condition for it's age (assuming 20 years+), there are portions that appear to be water affected (no surprise). Furthermore, I would be super grateful for ideas the best form of restoration (wood staining, oil, etc) or replacement (timber, concrete, etc)

Thank you!Overview of retaining wall with Storm water drain throughPeeling of timber at the bottom of some planksTree root through wall and visible water dampness on edgess

[Dave-1]

Good Afternoon @DIYDean 

Firstly Id like to say welcome to the Bunnings commuinty page There are so many differnt projects in here and I still havnt come across even a quarter id say!

Your retaining wall looks to be in pretty good nick, Not sure if there is any lean to it from the first photo or if its just the angle of the photo itself.

If ther wall is vertical then Id say leave it as is. That last panel with the white pool fence on top dosnt look as well supported but still looks solid. 

Overall Id say its a nice look retaining wall

I think I see the root through the wall. Id just chop it off flush with the wall. The dampness looks like some recent rain/watering or washing the car even as its only coming through at that point and dosnt look like its been there long term. (keep an eye on it for sure but think of if its been raining recently)

I am unsure on how to repaint it or if it can be restained as its copper logs type colour for tpouching the ground. I like the look of it and apart from maybe replacing/fixing that topmost cover plate all the way along I dont think id do anything. 

With that pipe out of the wall is that to a drain on the driveay above? Maybe check to make sure its clear all the way through.

And lastly I feel your pain for you having to dig up those palm tree bases, Ive had a few over the years and they are a pain. Dont let the fonds grow back! lol is about all the advice I can offer on that one. 

Dave

[EricL]

Hi @DIYDean 

Allow me to welcome you as well to the Bunnings Workshop community. It's wonderful to have you join us, and thank you for sharing your question about your retaining wall.

Congratulations on your new home. It's great that you've received excellent advice from @Dave-1. Looking at the photos you've posted it seems like the timber is still in good condition as there are no deterioration spots or large cracks that would compromise its stability. It is the last post that concerns me, but it looks like it was moved out of place due to tree roots rather than natural settling. 

If you are worried about the holding post, I suggest digging down to its concrete base and see if the post has cracked or the concrete footing has split. If it has, it will need to be replaced so that the retaining wall is not compromised.   

In regards to staining it, I suggest using a pressure washer in combination with an Oates Long Handle Deck Scrub Brush. The pressure washer will wash off all the dirt, grime and mould built up on the surface of the wood, the scrub brush will serve as back up to remove stubborn surface mould. the surface of the retaining wall must be clean and totally dry before you stain the surface. I propose having a look at the Intergrain 4L Merbau Exterior Nature's Timber Oil.

If you wish to see more stain samples, I recommend visiting your local store and having a look at the stain sample board on show at the paint department. You'll get a better idea of what the stains look like.

If you have any other questions we can help with, please let us know.

Eric

[DIYDean]

Thanks @Dave-1 and @EricL I appreciate your comments.

I can confirm that I had two retaining wall specialist drop by to have a look and they both had similar comments to you both, i.e, the retaining wall looks good and still has a few more years. I will be digging out the tree and planting elsewhere to prevent any further possible damage.

@Dave-1 the pipe through the wall is the storm water drain and seems to be working just fine, no leaks or clogs. The palm tree stumps are a killers, especially because I may or may not have underground electric and water lines going around the area, rip.

@EricL is there a reason you would recommend oil over water-based stain? I have read that oil will trap the moisture and may accelerate degradation. Again I am no expert so may be biased by some of the articles I have read, would appreciate your side to it!

Thank you gents!

[MitchellMc]

HI @DIYDean,

My illustrious colleague @EricL has recommended a stain and oil combo that will not only re-colour the wall but nourish it too. A standalone stain does offer some weather protection but lacks in the nourishment department. You might like to check out this discussion on How best to colour AND protect treated pine retaining walls? 

I don't believe that applying oil to the timber is necessarily going to accelerate the decay process dramatically as the timber is treated to prevent this. If you have concerns and are just looking to rejuvenate the colour, by all means, use an exterior stain product.

Please let me know if you have any questions.

Mitchell

[DIYDean]

Thank you @MitchellMc.