LSB

We had to have something like 8 reports to get Class Q, one was a structural survey to say that the barn was structurally sound enough to be converted to a dwelling. This survey said that some level of underpinning would be required due to the changed in Building Regulations. This was a bit like buying a house where you can have a basic survey or the full bells and whistles one. This first one was just to get planning which was issued with a number of conditions. We then had to have the full bells and whistles with cream on top survey to get building regs approval to actually build. This has taken about 2 years since planning was approved, largely because of Covid I will add. It was this 2nd survey that specified all the details about foundation depth. Ironically, the same company (different dept) also did our contamination survey, a condition of planning, and dug about 8 trial holes to check soil quality and for any gases, which had to be measured (on site) weekly for 3 months. It is from these trial holes that the SE got the details of the soil, they never even attended site, but looked at geological maps of where clay is. In fact in digging we have found much less than they said, only about 3m square in one corner and BR are happy for shallower trenches. We still have to underpin though a bit at a time. We are DIY self-builders so we are doing the conversion is about 5 phases and the first underpinning trials will be next week.

I copied into Word, didn't change it in here.

We are doing a class Q as Susie said and our SE said we need to underpin 75% of the existing walls, some as deep as 2.4m due to a patch of clay. The depth decision is down to the building control man. Currently we are digging the trenches for the 'not wall' i.e. there was never anything their and BC are coming Wed for 1st inspection and concrete (all being good) Thur. Our LPA said NO, NO, NO to knock down and rebuild, even though there will be a house there. The big paid with underpinning is that you can only do 1m at a time and our back wall is 25m long, so we have to do metre 1 & 4 & 7 & 10 etc., then 2 & 5 & 9 etc so that the existing wall doesn't fall down. We have current foundations of about 200 as well and the walls are totally solid and have been standing for 60 years, and we are only building single storey so it seems totally over the top. So, in answer to your question, yes you can underpin barn walls, but it is a total 'pain in the ar**' The difference for us is that we already owned the barn and land as part of our farm. Good luck and shout if you need any more help.

This is a subject close to my heart as I've very good at this, over the last 40 years I could have achieved much more if I didn't do this.

we ordered sand for a previous project which became a big cat toilet 😞 we also had it dropped on a big plastic sheet which broke down within a month in daylight and broke into tiny pieces. The rest of this sand is destined for underneath the lining of the pond as it's not usable for building, I think this was about 2 ton.

the build will be rendered / clad so same batch is not so important, this is just the external cavity wall, internal block walls and plastering for the future calculation. I fully intend to get the sand 'loose' delivered, but I still need to ask for an amount. At the beginning it's not so important. I'm trying to create a shopping list to send to the 3 BM's to compare their prices, even though some things, such as sand won't be ordered from them.

I'm creating a shopping list for quotes and am struggling to get the calculation for how much sand / cement we need. The whole external wall will be 226 sqm, but how to I convert that to how much sand / cement I need to order (in stages) for this. The readymix pour concrete was easy, all the suppliers have handy calculators where you put in your measurements and the little men in the computer give me an answer. Can someone here let me have the same for this. TIA

I wonder how much they went into receivership for and if it was the tax man what done it. Guess this will all come out next week. We spent 2 days at Swindon earlier this year and spoke to all the ICF suppliers, except Nudura who didn't seem to have a salesman around most of the time. We have just been so lucky. I'm sorry for all you guys who have been stung.

I've had this report for some time, we have been delayed in starting the build so it was paid some time ago.

was there any pre-app for the site, you could search on the LPA site and see what's around in the area and see who they used.

It's got nothing to do with not trusting the SE, it's just that we've found some things on the SE drawings that we were never told about or asked about, such as the wind posts and pad stones in the corners for example. I'm not saying that they are not necessary, but it would have been good if they had explained to us what things were. I've found out more from this site than from the highly paid professionals. Using your medical analogy it's like the doctor handing you a prescription, but not telling you what it's for. The SE knew we are very hands on renovating the barn, it's not like we are just handing the whole lot over to some big building company. The SE we employed is a large company and I'm sure there are lots of highly qualified staff, but apart from the initial structural survey to get planning they've never been here or asked us anything. We are trying to create our final home and it's already very dear to us and I just want to understand and be involved in everything. I don't need to know what these calculations mean, I understand enough to get the right foundations / beam and so on, I just want to know.

unfortunately he wasn't prepared to change it I'm interested, but it's not essential for me, except it I don't understand how do I know if I'm being bull-shitted by "professionals" trying to sell me things.

yep, all the calculations there are various typed tables and the actual drawings are using CAD, but even there the stuff around about beams etc is all hand written It's also on graph paper so there are times when the lines are the paper are difficult to distinguish from the calcs. When I asked him about it he just patronised me and said that it doesn't matter because professionals will understand it. To be fair the BCO hasn't had any issues.

this is the whole of this bit oops Fa should be Fa = b - 9.5 kn

I'm having another look at my SE report and most of it I just about understand. But, can someone translate what this line means, there are lots like these throughout for each different area. This specific one is Beam B3 Below follows the details about SLS & ULS & span, all of which I understand EW = 46.1 Kn Fa = b = 23.0 Kn m = 27.6 Knm infinity (can't find the symbol here) = 9.6mm ZyyREQ = ..... IyyREQ = ....... This document is hand-written so I'm hoping I can understand his terrible writing. TIA

I must have another look at the SE drawings, although all the text is handwritten and quite tricky to decipher in places. The BCO is happy with them so guess it must be there somewhere.

it's 120m from the road to the barn and from there to the far corner, going round the build is another 38m LPA also talk are archealogical concerns if we dig up the driveway, so bit of a risk to do even temporarily. The barn is up a hill from the road across a field so can be seen clearly, at least until the trees grow, but that will be 10 years so can't wait that long

moving on from my other post about foundations, I'm looking at the cavity walls above DPM looking at these as an example https://www.travisperkins.co.uk/100mm-blocks/hh-celcon-standard-aerated-concrete-block-grey-3-6n-440mm-x-100mm-x-215mm/p/700055 Celcon say that these can be used in both internal and external walls, but is that just sales talk as I've been told previously that we need 7.3n for external and 3.6n is only useable inside. Also, can you put external wooden cladding on these and render. Thoughts please ??? PS, only getting quote from TP for now, but using this link as example. HID likes these as they weigh about the same as a chunky kit kat 🙂

yes, 14 cubic meters

The dumper gets around okay, so I guess we could think about using that, when we had the extension built 20 yrs ago to this house the concrete had a chute which went about 5m, but the trench is 24m from the hard standing.

Planning explicitly says that we can't form any sort of driveway or track.

the problem isn't access it's the ground, as in a field which I'm concerned will be too soft for a concrete lorry The field went right up to the barn and some will become our garden. 1.5 ton digger slides around so hate to think what mess concrete lorry will get in. Also supplier said that with boom we need space for 2 lorries 🙂

I haven't explained myself, we don't want a cavity in the foundation. We are filling the 1m trench up to 950mm with concrete, then we are planning on 1 foundation block, the issue we have is the different BM's offer different foundation blocks. We weren't keen on using 2 blocks because the cavity between them under the DPM has to be filled with concrete which mean another readymix delivery, with the expensive pump due to the distance from hard standing. Or are you suggesting something else and I haven't understood (quite possible)

Right, thoughts please. This came to light when trying to get quotes. Total wall length of the whole build is 81 linear metres around the outside. We had decided on using Durox foundation blocks (215 * 315 * 350 - 11kg) laid 350 wide for 150 insulation compared with Celcon foundation blocks (215*300*450 - 22kg) with 100 insulation based solely on the weight. HID doesn't feel that he can manage the 22kg due to weight. Trouble is one BM does Durox and the others only do Celcon. Concrete - due to the location of good ground it looks like we need a boom pump, but they are very expensive. Therefore, I did a little table and taking costing into account the cheapest option is 950mm concrete and 1 foundation block, which will get us up to 1175 giving enough leeway to be 150 over GL for DPM. I then started looking at using blocks in foundation, but that is the same price by the time you put concrete in the middle of the cavity. Does anyone have any experience of Durox v Celcon foundation blocks.

And after lots of stress and calculations today we received the letter saying that we could start Instead of yet another Plan, Check, Schedule we had Confirmation of Reasonable Compliance. Now the real work begins and I can get updated quotes, but at least we can start making a real mess by digging trenches when it's been wet for weeks. Next step is to double check everything before we order anything.