Landscaping tips and suggestions needed for backyard w/ retaining wall

[TomY]

Hi all,

I'm looking for landscaping ideas for my backyard in south-east QLD. You can see in the photo that there's a retaining wall running down the length of the yard. Additionally, the boundary fence there is also a retaining wall down to the rear neighbour's property. My understanding is that moving my retaining wall back to the boundary line is going to bring the total wall height up to an unworkable height. Ideally I'd like to somehow bring the whole space to an equal level because it feels like an unfortunate misuse of space as it is, but unsure how I might achieve that given boundary regulations.

This photo is now a good few years old and the deck isn't in top condition so I'm also considering giving it an overhaul and/or rebuild, so I'm considering holistic options that involve a differently shaped deck

[Jason]

Welcome to the Bunnings Workshop community @TomY. We're so pleased to have you join us and look forward to reading about all your projects and plans for around the house and garden. We're sure you will get plenty of helpful information, advice and inspiration from our amazing community members.

Have you seen the excellent step-by-step how-to guide How to build a retaining wall by @Adam_W? It might be a good place to start. 

It might also be helpful for you to have a look at another of Adam's helpful guides - How to plan a garden makeover. His tips like starting with a wish list of what you want to achieve with this project, contacting your council, and developing a robust plan should be useful to you.

@MitchellMc will also be more than happy to assist when he is back on the site on Friday.

Jason

[Adam_W]

Hi @TomY,
to be honest that's a very tricky situation for a DIY'er.
In most council situations retaining walls that you can self-install without planning & approval can't be higher than 400 or 600mm (I think it varies in some areas).
Retaining in a boundary is a totally different kettle of fish as anything on a boundary (wall, fence etc.) is the responsibility of both neighbours unless it is written into the titles as otherwise.
I can't recall the exact details but retaining of almost any height must be a certain distance from the boundary and I'd bet you a penny to a pound that your wall is that exact distance for your council...
If you did want to do anything with that boundary wall you would need to talk with the neighbour (who may not want to share costs in this instance) and the new, taller wall would need to be fully-engineered, council approved & built by a licensed tradie assuming council approves it.
I'd be finding other landscaping ideas...

[TomY]

@Adam_W 

Hi Adam,

Thanks for the reply. That's all pretty consistent with what I was expecting, though I'm definitely not looking at doing any retaining work myself. As you say it's a complex problem and I'm far from an experienced DIY'er so in all likelihood most solutions will require outside help.

I've had a thought about decking that reaches out over and past the retaining wall, allowing that space to be more effectively utilised. From what I can find out, since the deck would be sitting closer than 900mm from the boundary it would require both a building permit and an alternative method of fire protection to meet the standards, such as a masonry firewall. However I can't find much information about how that works when it comes to decking (does the wall need to be simply the height of the decking, the balustrade, or the house's eaves?). 

I'm curious if anyone has had experience with decking close to boundary and what complications arose and how they were solved, and generally if there are any big issues I'm not seeing with this idea.

[MitchellMc]

Hi @TomY,

Constructing a structure within a certain distance from a boundary fence might require an engineers assistance. An engineer will be very well versed on what the requirements are to be compliant. Since the posts and footings for you deck extension will be upon and in retained soil, you would most definitely need to employ their services. Your retaining wall is designed to retain soil, and a decks weight might not have been taken into account.

Not only does an engineer provide the information you are looking for they also sign off on their plans. You'll likely need a permit from the council for the deck. To get a council permit, you'll need the planned work engineered.

Please let me know if you need further information or had questions.

Mitchell