Doing the Groundwork Yourself?

[PJW]

So, as our build comes closer, who has done there own groundwork? pre foundation work including trenches to receive services from the road. 

Our ground floor is 140m2. 

We are building on an old orchard so I need to fell a few apple trees and possibly a walnut.

Because we have trees we have yet to find out if we need to big down to 2m instead of the 1.2m standard. Soil survey will tell us this, so is getting a digger myself before to do this? Should I buy one or hire one?

As you may tell by the question, I want to do what I can myself, 1. for the experience 2. to save money. 

Any advise?

[Kelvin]

I’d probably buy rather than hire. 
 

Digging straight lines at a certain depth and width to match the dimensions on good level ground isn’t hard. Where it gets hard is when unknown problems rear up and how best to deal with them. Our 1.4 acre plot is on a slope so there’s only a small area you can easily build on. It needed a degree of cutting and filling and a bit of thinking about that all took skill and experience to do. I was chatting to my BCO and he marvels at the skill of the groundswork team on difficult ground and tight sites like ours. 

[PJW]

thanks Kelvin, our plot is relatively flat.. will need a small bit of levelling, however it's certainly not a slope. Good to know it's not difficult once we know the dimensions. Did you have any problems when doing yours?
Just out of interest, what did you do with all the soil, stone, rocks you dug up... did you manage to repurpose any of it? or simply just had to pay to get to rid of it?

[Kelvin]

Just to be clear. I never did ours. I had an excellent groundswork guy. The only digging i’ve done are the trenches for various services around the place. 
 

Top soil you want stripped and piled up with something over it. All the vegetation off it too obviously. Because we did cut and fill to level ground we re-used most of the material but that needs rolling in layers. You then dig back down to solid ground for your trenches. Stones and boulders we piled up to use in the dry wall. We didn’t need muck away for the excavated stuff we didn’t use (mostly from the retaining wall) as the farmer took that. One thing we did do that made an enormous difference is put down loads of MOT all around the house (4m min for us) plus a big offloading area. I’m glad we did this as without it we couldn’t have offloaded much very easily! It also means our site is mud free and dries very quickly when it does pee down. This means the slab and garage slab are both clean. 
 

 

Edited May 24, 2023 by Kelvin

[saveasteading]

On our project we used a groundworker at first. They were good workers and machine operators and had whatever the highland is for blarney. Some things that passed bco and our family team were not actually good, and they also got greedy. And they knew best!

 

The second half was all done by my son in law in the digger, and my daughter plus friends and family.

They had been reluctant to fire the groundworkers but realised what a good decision it was when they did it themselves. 

So half the slab (grade, fill, stone, concrete blinding, pir). Specialist did ufh and the screed.

Then all the drainage with me(*) on site first week, after which they were utterly confident. From " we can't possibly do it" to " I am so glad we did it ourselves".

 

They hired a 5T digger on and off, and an occasional dumper. I still think that was the right move, anyway there seemed none to buy cheap.

 

Can anyone diy? No. Apart from the sheer hard work and being good with the machine, it is often in rain and mud.

Can you do the levels and other controls? Most can't and they don't know they can't.

 

The trench went to 1.6 deep. More than that would have needed a bigger machine. The site was sand so never soft or muddy...beware mud.

 

Saving over 170m2....simplifying the design saved £12k or more. Diy saved another £20k or so.

 

NB things go wrong, even when planned. Mud is your greatest enemy. You would need to study the subject before starting and throughout. There is a lot to learn.

 

Muck away? Avoid it as the cost is high.

Strip topsoil and vegetation to one heap and it will compost to half the volume, then spread it on completion.

Earth....surely you can change some topography.  Don't forget how much comes out with drainage.

Worth many £k. In any case it is well worth shifting the earth (spoil is the jargon) away from the working area immediately.

 

*for clarity: surveying and construction is what I have done for decades. Always with groundworkers but heavily supervised. I wouldn't want to be a groundworker but would if there was nothing better to do.

 

If you feel confident then you will probably be fine. Don't rush it.

[Dave Jones]

there will be a local man with a digger, 3-400 a day with machine. They will be 5x faster and neater than trying to do it yourself. They will also have contacts for muckaways etc

[ProDave]

There are quite a few of us on here that bought our own digger and used it for most of the build.  I did my own foundations up to the concrete then the builders turned up and took over from concrete pour onwards.  They started off by saying I would never survey it, mark it out and dig the trenches in the right place on my own, but then admitted I had done a very accurate job, there was just one corner out by about 100mm and that was because I could not get the digger square on for that corner.  It took us 10 minutes with a shovel to square off that corner to get it right.

 

I used it for all the site preparation first, services, moving soil around and it's final task before I sold it was the basic landscaping of the garden.

[saveasteading]

1 hour ago, ProDave said:

bought our own digger 

Did you have any breakdown or maintenance issues? That would be my concern, especially having seen our (business) groundworker suffer when his bargain purchases broke down. The worst was losing a track, and he wrote it off and gave it away to any collector.

[ProDave]

10 minutes ago, saveasteading said:

Did you have any breakdown or maintenance issues? That would be my concern, especially having seen our (business) groundworker suffer when his bargain purchases broke down. The worst was losing a track, and he wrote it off and gave it away to any collector.

No I was lucky, but it would not have been a machine to go contracting in.  Fuel filters kept blocking, I bought a job lot and replaced them regularly, probably something nasty in the tank.  And I broke the king pin that the boom pivoted on. That could have been messy but it hung on one side until I could get a new pin and drove the old pin out with the new one, so it never all collapsed.  the tracks were steel but well work, everything was old and well worn, but it worked and at the end I sold it for exactly what I paid for it.

[Jenki]

1 hour ago, saveasteading said:

Did you have any breakdown or maintenance issues?

Oh yes...

I've got an old 550 backhoe, and its done me proud, but the back swivel motor is pouring oil, so I have a catch bucket, filter and re use.

The steering pistons regularly come loose and fall out of the pinion, did today when I was unloading an artic🙈. Then not 3 hours ago a hose on the backhoe burst while I was trying to level 20t of crush and run.

Would I buy again? Yes. But will be glad not to have to bleed the injectors when I forget to check the fuel level( long length of wood in the tank).

 

[saveasteading]

Have spoken to the team. They used a 3T excavator costing £250/ week.or £750 for 4 weeks. It comes on its own trailer so collection is by customer with towball.

 

There were a lot of these hire periods so it added up.

The grab function turned out to be very important as it can lift boulders etc.

 

Another theoretical time they might buy new or nearly new and sell at the end.

 

But for heavy jobs a big jcb with operator can do stuff in an hour rather than days if at all. So there has been that on top.

 

 

Dumper cost £90/week but that is no longer achievable for some reason, and £250/ week is demanded (plus expensive delivery).

[Chanmenie]

I agree with @Dave Jones.

I was going to borrow a digger and do my own, but found a local guy who had all the equipment, I marked out the site and levels.

Using an 8 ton digger with myself holding the lazer level he dug perfect trenches,

they were straight as an arrow and within 10mm of required depth all round.

It didn’t take him very long and he took 200 ton of muck away at a very reasonable cost.

I then arranged for a local company to pour the 300mm strip footings then did the blockwork up to DPC myself.

So with a mixture of DIY and Trades I got very accurate trenches and level, square 

foundations for a much reduced outlay

Edited May 25, 2023 by Chanmenie

[Canski]

I just had a bill for removing a grab load of tree stumps. I knew it might be a bit more than the usual £220 for mixed soil and rubble but £320 was a bit of a shock. 

[twice round the block]

I had an old international digger with 3 into1 front bucket on my first build in the 80's, this time I've got a small Volvo 360° with 3 buckets but I've purchased a ripper which is great for removing tree stumps x26 and redundant footings and concrete piles.

I've hired in diggers over the year's for various projects, so I consider myself a skilled operator.

It's handy to own your own so you can use it when you get a dry spell. I never use it when the ground is wet because in a short period of time you can turn the site into a quagmire and end up making more work for yourself.

 

If your confident in operating one, buy one but be careful you can cause some expensive mistakes. Never trust a CAT Scan for pipes and cables, a tooth on the bucket will find them for you.

Wear a seat belt when pulling out as it is easy to get the machine on its side and also when tracking backyards when you find yourself in a hole you dug out earlier. 

In the right hands it's a precision machine, in the wrong hands it's an extra 6 cubic meters of concrete in the footings.

Insure it, they get stolen daily.

You can't get your VAT back on one.

Buy from a dealer if you don't know what your looking for.

Resale weekly site has most of the dealers advertising on there.

[jfb]

I bought an old Jcb 3cx which proved reliable luckily and is useful for many things I have going on. Not the best for precision trenching though. Had access to small diggers for some things. 
but….. you can get a lot done quickly with the right equipment and a good operator and I had an old boy who used to do groundwork’s help out and it was invaluable. If you don’t have a use for the machine post build and have a clear plan of what you want to do I would be tempted to hire someone in if you can find someone good.

[MikeSharp01]

On 24/05/2023 at 17:46, saveasteading said:

Did you have any breakdown or maintenance issues? That would be my concern, especially having seen our (business) groundworker suffer when his bargain purchases broke down. The worst was losing a track, and he wrote it off and gave it away to any collector.

We have our own digger, for a few more weeks. We got is second hand and replaced the motors at the start as one was leaking, and although we have had to re-build one of them since, fit new hoses in places, replace the aux hydraulic connectors - which were jammed, change the oils & filters a couple of times and fit new seals on one of the rams otherwise it has been very cost effective. I hope to sell for about what we paid for it in the summer so although inflation has nibbled away it it will go one for a long time yet.

[LSB]

We have done everything ourselves, except drawings from architect, SE and for BC.

I even submitted my own planning app after 2 refusals and got it approved.

 

If you look at my blog you will see what we've been through so far.

 

It's a very very slow build, just got the first wall to DPM level.

 

BS officer (private) was very happy with our trenches and said the others can just be photos.

We do have SE drawings which specify the depth, in our case it varies between 1m on sandy soil and 2.4m on clay / roots.

The trees were cut down, most of them dead already a few years ago, for various reasons hence the trench depth.

 

That said when BC came out for our 1st trench (1m) he said there was no need to go that deep on our soil and 450 would have been plenty, we are single story.

We have digger, dumper and every other tool known to man, well it seems that way, 7 sheds.

 

The main reason we decided to do it was because we had 4 groundwork companies out to quote and not one of them even bothered because of the depth where the clay / roots are and underpinning needed (barn conversion).

Too many easy jobs out there.

 

We are now tackling the build in 4 sections starting on the easy one to gain experience.

 

So, perfectly possible with the right tools, learning (books & internet), build hub and taking it steady.

I would also recommend private BC because they are working for us, not the council.  Still the same checks, but more flexible.

The SE did say that the trench depth can be approved by BC so we are going to do step trenches and just dig down until on 'good' ground and not just dig to 2.4 around half the walls.

 

Our build is 240m2 on one floor with 87m of wall that needs trenches or underpinning.

where the existing walls are they are single skin so we are building a 2nd skin that needs it's own foundations.

 

[saveasteading]

13 minutes ago, LSB said:

hence the trench depth.

Yes I agree that 2.4m is prob very conservative. But don't accept what a groundworker says. Even for bco make sure they understand clay and heave.

I think nhbc says 900 min and that seems sensible. 

 

I hope the new foundation for 2nd skin is at the same level as the original.

[LSB]

16 hours ago, saveasteading said:

Yes I agree that 2.4m is prob very conservative. But don't accept what a groundworker says. Even for bco make sure they understand clay and heave.

I think nhbc says 900 min and that seems sensible. 

 

I hope the new foundation for 2nd skin is at the same level as the original.

The different ground levels is something that we are working on, but the existing barn had 4 different internal levels, but on digging this out, not usable, it's very odd with 3 - 5 different layers of concrete all on top of each other.  They do all seem to go down to the same level at least.

We can only assume that whoever built it (long gone) had a cheap supply of concrete because of how much there is.  No rebar, no insulation, no DPM except for one area.  These days it would be about 50k worth in my estimation.  And, it's not attached to the 200mm wall foundations, just laid inside so not a raft.