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Retaining wall cost question

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Hi,

We are building on a sloping block and need to put in a retaining wall behind the house. So far, I have been quoted about $25,000 for approx. 50m of treated timber wall (terraced - 2 walls of about 25m each), no more than 1.4m high, with steel posts.

They can't continue building until the retaining wall is in, but I have no idea if this figure is high, low, or, about right! Can anyone advise?!

Thanks.
Warth
Hi,

We are building on a sloping block and need to put in a retaining wall behind the house. So far, I have been quoted about $25,000 for approx. 50m of treated timber wall (terraced - 2 walls of about 25m each), no more than 1.4m high, with steel posts.

They can't continue building until the retaining wall is in, but I have no idea if this figure is high, low, or, about right! Can anyone advise?!

Thanks.


I got quoted the other $275.00 per sqm. Basically a 25m long wall 1m high, would cost about $6,875.00, I think the trouble you are in is that if the wall is more 1.1m high, so you need an engineering design. Thats what my council says anyway.
We have built through the builder retaining walls now to well over $25,000. The two side ones were for the house build - the rear one because it would be too hard to do later. All three walls had to be engineer designed. We were advised that we could have got it done a lot cheaper elsewhere but when we went looking for quotes couldn't and also we wanted to be sure that the builder would be satisfied to build on it. The hidden costs will be building new fences because of the height of our new back yard.
anything over 1.2 needs engineering

a council wont supply permit, a building surveyor supplies permit inc. inspection/s

1.4 with h and c beam at the mentioned price sounds reasonable but it is always situation dependent
davinci does council permit height requirement depend on the coucnil? i always thought the cut off was 900 high. not more. that extra little bit could make a big difference.
it might be council dependant, i am only going of the council districts i have worked in
hmm I'll have to have another look at our council details. would love to do a retainer just over the 1m mark but thought we were limited to 900 without having to get shire approval. Might be because we originally had considered a 1200 on on the boundary and the council weren't happy about it.
does seem expensive for timber I would be looking at other types as in time timber will not hold over 1.2 need council approval my husband is a bricklayer
DH said it was definately 900 where we are. great news for you if its 1200 though.
It seems to vary a little, it 1000mm and above here that needs engineering.
sorry, to clarify a wall 1.2 mtrs in height or above needs to be permitted etc
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