Digging a massive hole with a micro digger?

[tombodge]

Im thinking / dreaming about building an underground bunker man cave in my garden fairly big around 25 m2 3 meters deep.

It would be 4 meters from the house and 2 meters away from all the fences. So wouldn't need planning ect.


The only thing I could get into my garden is a micro digger and micro dumper with a skip on the drive.

Would it be possible to dig this kind of hole with these sized diggers? and does anyone know ruffly how long it would take.. Assuming the ground isnt full of rocks ect.


I think the depth of the diggers reach is about 2 meters so i guess you would have to dig an excess ramp in ect.

 

[tombodge]

I guess im wondering if there's a cubed meter per hour figure you can get from somewhere. it would have a 700mm ditching bucket

 

[r896neo]

A 3m excavation could be very dangerous depending on the ground conditions. It should be shored up at about 4 ft high but by the time you get to 2m you would definately want to be careful. You could grade the top of the edges away at a 45deg slope until the inside structure is built and then back fill the top metre or so?

You need to consider loading the dumper. A minidigger needs the dumper being loaded to be level or preferably a little below so you'll need to have the dumper down in the hole too.

I honestly thing your totally bonkers. Unless you have a a mate with a grab lorry working for free you'll be bankrupt. 20 x 8 yard skips at a guess?

I reckon between muckaway and machine hire you could easily spend 3 grand on the hole alone? Plus building a structure capable of retaining the 3m will not be cheap either. Building underground is fraught with problems and always very expensive

 

[JohnD]

you are allowed 30m2 internal floor area for a fallout shelter without planning or BRs, provided the excavation depth is no more than distance to adjacent buildings (it was specifically excluded from regulation). You will need RC construction and excellent protection from damp penetration. These days use drainage tiles and a pumped sump to cope with seepage. In wet soil it may float up.

 

[noseall]

I honestly thing your totally bonkers.

I'm guessing this is the case or the OP extremely naïve or is on a wind-up.

 

[tombodge]

lo I watched this.

the whole build is on there as well in 5 separate videos.

I have no idea how much it cost todo but Im a coded welder and capable of doing it.


If it came in around 5-7k I think it would be well worth it to add a 25m2 room onto my house. Pool table bar sound system ect. No naybours to worry about.

I cant really extend my house much so it would be ideal.


My biggest problem is it would have to be done with a mini digger/ mini dumper with large skips on the driveway

 

[noseall]

£5-7k will buy you three parts of the tanking process.

A habitable sub-terranian space will come in at three or four times the cost of one built above ground.
Above ground buildings cost upwards of £1000 p/m.

 

[r896neo]

Every extra foot you go down the costs multiply exponentially so perhaps you could simply bury it halfway? Like 1.5m into the ground, 1.5m out?

I cant stress enough how potentially dangerous and difficult digging a confined hole as deep as that could be if you have no experience in excavations. The only safe way to do it without sheet piles or shoring would be battering the sides back extensively and then majorly backfilling once your done. In a field this would work well but in a garden maybe not, unless your neighbours are super friendly

You will also may hit the water table depending on the lie of the land locally. that will bring all sorts of fun and games.

Your mad but go for it as long as you plan it well and work out the costs involved before digging, it would certainly be some achievement!!

 

[tombodge]

After thinking surly it wouldn't cost quite that much I did a really ruff google price up from the stuff he used in his. Very very ruff but I came up with 38 sheets of 8x4 4mm steel £4500... 30 6m lenghts of 50x50 3mm box.. £1500... 60 m3 waterproof concreat .. £6000... digger dumper £600.. £500 hardcore/ top soil. say another 1500 for rsjs and metal mesh and your around the £15,000 mark for the basic shell. doesnt really tell me alot as you might get bulk savings on the steel ect but I recon its defo around the 20k mark +- 5k eather side of that lol not including labour problems finishes.


I dont think that bunker quite cost him £90,000 but perhaps if you got a firm in todo it for you including finishing it might?

 

[noseall]

After thinking surly it wouldn't cost quite that much I did a really ruff google price up from the stuff he used in his. Very very ruff but I came up with 38 sheets of 8x4 4mm steel £4500... 30 6m lenghts of 50x50 3mm box.. £1500... 60 m3 waterproof concreat .. £6000... digger dumper £600.. £500 hardcore/ top soil. say another 1500 for rsjs and metal mesh and your around the £15,000 mark for the basic shell. doesnt really tell me alot as you might get bulk savings on the steel ect but I recon its defo around the 20k mark +- 5k eather side of that lol not including labour problems finishes.


I dont think that bunker quite cost him £90,000 but perhaps if you got a firm in todo it for you including finishing it might?

Dream on Tom and be sure to post your 'habitable' results on here.

 

[noseall]

Very very ruff but I came up with 38 sheets of 8x4 4mm steel £4500... 30 6m lenghts of 50x50 3mm box.. £1500...

Basically, you are building a fuel tank.

 

[JohnD]

I am surprised the nutter in the video went for steel inside. I suppose he used it as the inner shuttering. It looks to me like it will suffer bad condensation and rust.

 

[noseall]

Very very ruff but I came up with 38 sheets of 8x4 4mm steel £4500... 30 6m lenghts of 50x50 3mm box.. £1500...

Don't forget to factor in a crane.

 

[garyo]

I saw a TV show where a fella buried a shipping container to do something similar. They're great value but you'd still need a bloody great hole!

 

[tombodge]

I am surprised the nutter in the video went for steel inside. I suppose he used it as the inner shuttering. It looks to me like it will suffer bad condensation and rust.

I thought the same to be honest. Although i recon it probably does a fairly good job. Its 100% waterproof and the concrete should stop a lot of water and oxygen getting to it so if it does rust it will be very slow. It does the dmp shutting all in one go. I cant help but think there would be a cheaper way todo it though