Retaining wall issue missed by surveyor

Mellor

https://www.boards.ie/discussion/comment/122053514#Comment_122053514

just checking, as many wouldn’t have a clue.

In that case, what are the major tasks and the cost you’d think they should be?

https://www.boards.ie/discussion/comment/122053544#Comment_122053544

$100k is a sky high estimate. But “a few grand”, that’s also miles off.

Deeec

https://www.boards.ie/discussion/comment/122053736#Comment_122053736

They're not even builders - they were still able to build the wall themselves and they done a really good job.

If anyone pays €20K let alone €100K for that wall to be built they need to consider themselves really really stupid 🤣

Smee_Again

https://www.boards.ie/discussion/comment/122053797#Comment_122053797

I bet it wasn't a retaining wall though.

sprucemoose

https://www.boards.ie/discussion/comment/122053840#Comment_122053840

or if its meant to be a retaining wall, id bet there was no actual structural design input and was a case of 'ah sure itll be grand'

which wouldnt surprise me if it were the case with the OPs wall too to be honest

Deeec

https://www.boards.ie/discussion/comment/122053840#Comment_122053840

It was a retaining wall and it was a bigger area than the OP's job. Admittingly they were not paying themselves for the their time or labour just materials. They genuinely done a good job and didnt find it too much of a hassle. They do have a good general level of construction and engineering cop on though despite not working in the industry. My fathers in his 80's and in good fettle - he still would tackle most construction jobs on the farm rather than get some chancer to do it.

I dread to think what it would have cost if they got someone else to do it - even with so called highly paid 'skilled builders' the job can even end up being poor.

Im just highlighting that some jobs that are quoted high by builders dont warrant the high price at all. Also its not the kind of work most good builders would be interested in doing - the OP will find it hard to get someone to do it.

Smee_Again

https://www.boards.ie/discussion/comment/122053853#Comment_122053853

Looks like you were right.

Calahonda52

https://www.boards.ie/discussion/comment/122053736#Comment_122053736

31 posts in and we are already in the BS arena, just like the Baltimore bridge disaster, every TD&H suddenly became Phds in bridge design, where the Phd stands for piled higher and deeper

T-Maxx

...

Dr. Greenthumb

Been a while since I worked in Ireland but based on the dimensions the OP gives I'll give it a shot. 5.4m high (18') x 23m long = 124m2.

Block on flat; 124 m2 x E60 / m2 = E7,440

Demo and disposal E5,000

Engineering E3k

Allowance for earthwork E5,000

Plaster & paint (1 side) E1,500

Contingency at 25% E5,500

Rough cost of E27,500 based on getting outside contractors with minimal risk built in as I'm assuming OP isn't doing it himself. Risks are that it undermines your back yard when you take it out and based on the proximity to your house that could be an issue. I'd imagine to prevent significant ground movement you should piecemeal it and take a build as you remove which would increase the demo cost as now it is drawn out rather than done in one go. Given that you said the retaining portion is 12', from a safety perspective it would probably require dirt removed on your side so people are not working under an unsupported 12' earth bank. If you take all that risk into it, which you will be pushing on to the contractor, the slower work, the safety measures needed, to get a contractor I don't think you'll have too much change out of 50k for a proper job.

I would look at another option, 8" top to bottom over the height of the wall isn't huge. I would speak to the council and see if you could get access to that side and build some buttresses. You could support the wall temporarily while you dig the foundations etc. and the buttresses would then stop any further movement. You'd still need some engineering input but risk and cost would be significantly reduced with way less hassle to you. Trees may need to be removed but as another poster mentioned these maybe a part of the problem in the first place.

lmk123

https://www.boards.ie/discussion/comment/122054058#Comment_122054058

Ah yes the usual BS, but did you not see that his father and brother who are not builders could do it for a fraction of the cost. I’m sure when they’d be half way through the job and the wall and backyard collapses into the council land they’d fix that for a few hundred quid.

Grassy Knoll

the prices you are being quoted are probably for a mass concrete wall, which probably would have been a better engineering solution from day 1. Seems to me six foot of ground behind a block wall was always a bit light. Also the persistent rain over time is not a help. Given where you are now, I agree a buttress solution could be an option.

Mellor

https://www.boards.ie/discussion/comment/122053929#Comment_122053929

Built an retaining wall over 25m long with a greater level difference than the OP? Without a builder or engineering. You'd need to get through a very wet winter before you can call it a success. You've no idea whether it will stand up yet.

A bit ingenious to compare materials only to the OP would needs to get a contractor in. It's not use labour, it's the design, certification, and insurance that goes with. All of which is missing in the self build scenario.

Mellor

https://www.boards.ie/discussion/comment/122054737#Comment_122054737

That's a decent estimate. Prob need to allow more than 18ft as you have to add for the subground portion on the low side. Could be builders margin on top, structural certification, etc. A big factor is the garden as you identified. Removing the unsupported bank will knock out half the paving and the planting beds. Adding those costs are starting to get up there.

sydthebeat

Also not a very intelligent place to construct a raised planter bed

orcahardking

There isn’t a raised planter bed. The flowers are at ground level, the patio is raised to the house level though.
Thanks all for the info, I’m currently in the process of finding a structural engineer to design the solution which I then need to share with the council!

Hooked

https://www.boards.ie/discussion/comment/122054737#Comment_122054737

Thanks for saving me the hassle… 100 grand. Jokers.

sydthebeat

https://www.boards.ie/discussion/comment/122055856#Comment_122055856

It's possible that, at only 8" over an 18' drop, that a simply buttress on the councils side will suffice

chooseusername

https://www.boards.ie/discussion/comment/122055633#Comment_122055633

Reading this from @orchardking

"The wall is about 12ft high on their side and 6ft on my side"

Wall is 12 ft high. Lower 6ft is retaining wall, top 6ft. is op's garden wall.

6ft. high buttresses, get Council engineer involved .

Edit,

Looks like your surface water drains down inside the retaining wall, that would not help the situation ,

wall.jpg

T-Maxx

OP are there any signs of movement or settlement in your garden? Subsidence, cracks, etc?

orcahardking

There’s a definite slope to the paving and the wall has separated from the small wall. No idea if it’s new movement or old so will have to see what engineer says.

DataDude

https://www.boards.ie/discussion/comment/122056345#Comment_122056345

If you have a report from a qualified engineer from November saying the wall was in good condition at that time, then you must have reasoanble grounds to say ‘an event’ (e.g. subsidence, tree root growth etc.) has occurred to create this issue.
Would insurance not cover this? I would have thought a boundary wall is typically in cover? The insurer could choose to pursue the engineer who provided the report for a recovery if they felt his report was incorrect.

Lumen

FWIW there's a few of those type of retaining walls been built on the new estate next to me. They're all reinforced mass concrete and then "stone" clad where required for aesthetics.

I assume they do this because it does the job and is cheapest.

There's good access as it's right by the road, so no issues with pouring directly from a truck.

Grassy Knoll

let us know,what the engineer says, I’m intrigued !!