How much for labour for an 8-9m retaining wall?

[CumbrianRed]

Hi, I've been really struggling to get help with a concrete block retaining wall. It's on a slight slope in our garden and we're wanting to level it for a garden office.

It would be 8-9m long and 90cm high. It would need a concrete base and a bit if block foundation. The ground is soil then about 10 inches down clay. The ground is clear. It will probably need to be twin skin.

We've been trying to get someone to just do the wall. We had a guy come and say it would take about a day for two of them to come do the wall, but he didn't have time. Then we've had quotes from two other guys that it will take two of them about a week.

Why is there a 5 times difference in how long people think it will take? We're struggling to understand the huge jump in price.

How long should a twin skin 8-9m block wall take to base and lay?

Thanks for your help!

 

[CumbrianRed]

To clarify, we have 95-100% of the materials on site already.

 

[lostinthelight]

Any special reason for cavity, flat is normally better for retaining wall

 

[CumbrianRed]

Any special reason for cavity, flat is normally better for retaining wall

No, I'd just been told that by one of the guys. Why us flat normally better?

 

[lostinthelight]

No, I'd just been told that by one of the guys. Why us flat normally better?

Stronger but if your guys are the “experts” who’ve seen the job??

 

[freddiemercurystwin]

Rule of thumb for mass retaining walls is the thickness should be about 1/3 of the height, so at the base it ought to be a block on it's side + one vertical.

Lots of threads on retaining wall construction on the forum and how to minimise blown render etc.

 

[Dereekoo]

Rule of thumb for mass retaining walls is the thickness should be about 1/3 of the height, so at the base it ought to be a block on it's side + one vertical.

Lots of threads on retaining wall construction on the forum and how to minimise blown render etc.

Unfortunately some times the hammer hits your thumb and that hurts

 

[foxhole]

Build on legs?

 

[freddiemercurystwin]

Really it all sounds a bit vague, you need an actual design that they can follow, then you'll get like for like quotes. I would think a day or so for setting out and excavating the trench, is there digger access? Cast the foundation the next day, then a day or so to build the wall, then another day or so for rendering and capping if applicable. Note the job may need to be split into chunks, you shouldn't really build your wall until your foundation has cured a bit. Also be wary of your planning permission, if you're building on made up ground, the 'ground level' used is the existing one before you excavate.

 

[CumbrianRed]

Thanks for the helpful comments. @Freddie that sounds very sensible, where could I find a reliable design from? I don't want to have to employ an architect to create it as things are very tight.

 

[Dereekoo]

Try looking at NHBC garden wall

 

[Dereekoo]

And then Gooogle this to see what may be required for a proper design. "The Design of Brickwork Retaining Walls"