LSB

arch just says 'base' level and doesn't show them on the drawing focusing on the insulation. thanks for the prompt reply

I need help 🙂 We are building block / block with render / cladding but are struggling with weep vents and cavity insulation positioning. Our SE drawings just say 150 full cavities, simple enough, but then I've looked at loads of books, websites, diagrams, spoken to arch & BC and they all vary on where the weep vents go and where the insulation starts and if we even need weep vents. Our founds are 1000 deep with 850 poured concrete. Then below the DPM there will be 1 block on its side, so 110 high (incl mortar) and 1 block std layout, 225 high (incl mortar) totalling 335 incl mortar. So, this equates to 150 below FGL with 185 above FGL to allow for the min of 150. This equates to mortar (10), side block (100), mortar (10) plus 30 of the lowest cavity blocks below FGL leaving the 185 above ground up to the DPM. This is all pretty straightforward except; Does the insulation go right to the bottom of the cavity with 30 'underground' and 185 below DPM or does it start at the DPM (or somewhere else completely). If this is the case then do we need to put a thin mix of concrete in this cavity. I asked the architect who said it up to us or BC. Surely this will have the potential to get damp and rise up, BC not replied yet. Obviously the DPM doesn't go across the cavity so there would be nothing to stop moisture going up and up. The weep hole, the arch said at 'base' level, so I asked where that is and they said FGL, but surely if there is a puddle or heavy rain / wind combination it would enter the cavity in through the vent rather than exit. The render / cladding won't be going to ground level so weep vents will be fine at FGL, but if they are higher then won't that allow damp to sit below the vent and if insul is at the bottom just make that damp. Insulation is mineral wool, which raises the question if this starts at DPM and, supposedly, doesn't need fixing then why won't it just fall down to the bottom of the cavity. I am getting so much conflicting information that I am hoping that this place will have a more definitive answer for me. TIA Jill

we got the architect to do the drawings, he failed at 2 apps so we parted ways as he was refusing some things the planners wanted saying they weren't necessary (ground survey). I just got an SE, got them done along with tree, bat, small furry animal surveys, resubmitted and passed. I did make sure I had permission to use the drawings. Since then I've gone back to the arch to get the BC plans. But now we are doing everything ourselves.

What is your soil type, don't forget roots are generally as big as the trees and if you have clay then you will have problems with roots. We had some trees on our boundary, these were killed by the power company by over enthusiastic pruning to get them away from the power lines. About 4 years later we cut them down as they looked awful. A few years later we submitted planning, they used Google Earth (not just the most recent) and asked where the trees were as they affect the soil, even long after the trees were gone. There were probably about 8" in diameter.

In all my research I've found this online book about the architecture of building houses. This lady does architecture student books covering a number of subjects and I found out about her when looking for details on the latest building regs. See below, as well as residential she covers Basements, Passivhous, commercial and some others and I really like her diagrams. But, her name is Emma Walshaw, and she's done a number of online books call 'Understanding Architectural Details'. I've bought the Residential construction one. https://www.firstinarchitecture.co.uk/ Above this she has also answered some questions for me. Not cheap, but having bought lots of books this one has provided me with more info about the theory of building requirements than anything else.

how many square meters, looks huge compared to ours

it's inside the blocks, drawings buried currently, but I'll show picture later, SE also said footings of 2.4m but BC say 1m is plenty as it's not the horrible type of clay, but sandy clay and we are already 3m below the field next door, which is clay. SE does agree that BC have the last word. SE also used Google earth to look from years ago when the trees were there, they were removed about 5 years ago.

Am I allowed to ? I wasn't sure But, her name is Emma Walshaw, and she's done a number of online books call 'Understanding Architectural Details'. I've bought the Residential construction one. https://www.firstinarchitecture.co.uk/

If you wanted to buy something then you would have heard.

I've not actually investigated yet, but it is specified by SE, looks thicker though from his drawings, probably about 50mm

how annoying, hope it's not too difficult to sort out, or too expensive.

I've recently come across an architectural training book, online only, designed for students, but it's been the best thing I've found. Quite expensive to get the download, but lots of diagrams and simple explanations, not how to just what things mean in a way that I can understand. The author has also happily answered some questions for me in return for me giving her a statement for her website.

This side is sand, to the extent where we had to be careful of collapse as it was so loose, but done now, a few minor slippages and 2 cubic m more concrete than planned due to the width in places. No trees this side, this is the North side of the barn, the south side is at the edge of our land at the base of a bank. There were trees all along the top of the bank, but they were killed years ago by the top reduction done by UKPN because of a power cable, but still roots in the ground so we have to have a root guard in the foundation wall. The bank is clay, but not sure what type yet or how far on to our land it goes. The BC man said he didn't think it would be any issue at all when he had a quick look because we are about 3m lower than the field. The 2nd pour is going to be the North West side and is sand again, BC said 450 deep and just send photos. This is the whole reason we choose private BC as I think they are more flexible, from what I hear. That won't be for a while though. Next is to build the wall where we poured today and dig out more from the floors whilst we can still get in.

Building Control - he say YES In fact, he said that the trench doesn't need to be as deep as 1m in our soil and for the next section he only wants photos as long as the soil is the same and it only needs to be 450 +

Just got back in from finding lightweight tarps, weed guards and some old DPM, enough to cover the trenches ready for after the pour. We have a very large, very heavy duty tarp for the tractor, but I didn't want to use that as I suspect it would just collapse. I shall post some photos after the deed is done. The BC said he would be here 1st thing, no idea what that is to him The pour is scheduled between 12 & 1. BC is off to one off to Heveningham Hall after us and will come back later to see the concrete in situ. Then, it's wait a few days, until next week, and the laying of blocks can begin, slight issue with that is they haven't actually been delivered yet, should be tomorrow. Maybe I should have the local vicar doing a 'laying on' of hands to bless the build, she probably would be quite happy. It's taken a long time, but thanks for help, until the next question 🙂 On the temp note of large builds, I worked on a factory build 2 years, we had to sink 30m piles (make up ground) with 3m foundations and that had a no. of temp gauges

Oops, I moved from North Somerset to Suffolk a while ago, but haven't updated the location on here 🙂 No frost forecast, as of yesterday all day rain was forecast, but that's gone away thankfully, just because it's horrid being out in the rain

We are supposed to be having our concrete poured tomorrow. The weather forecast is for dry weather at about 7 degrees, but with the wind chill they say 3 degrees. As you shouldn't have concrete under 5 degrees ideally is this likely to cause an issue. The weather is not proposed to get much warmer for the next week or two, much colder than expected this time of year. We have wind coming to us straight over the sea from Norway, although we are a mile or so inland there is nothing to stop it. Thoughts please TIA

Well, it's really happening. HID left work last Friday, spent the weekend fixing the horses fencing, but it didn't matter as he can now work on the build. I've created a very detailed project plan for his for 3 days and intend to keep this going as he works much better this way. This will approximate timings which will no doubt go out the window. We did have an issue last week, he had dug a trench, we had torrential rain and one side fell in, some of our soil is very sandy so fine to build on, but need almost digging, inspecting and filling in one day. He has today dug the main parts of the first trenches and BC are coming Thurs am to look with concrete coming Thur lunchtime and then BC coming back later to look at this as he's got a local inspection as one of the local mansions for a few hours. Still lots to do for this, one end needs to be shuttered to allow for the underpinning, we need to fence the area for safely before someone (probably me) falls in. We need to put level markers for the depth and check if any of the sides need supporting. Luckily the weather is supposed to be good this week. Not a very big update, but so excited to be doing something except pouring over reports and plans.

You're right, they only need to take £100 + on card for us to get the cover, more would be better, but that's sufficient. We have a local auction house that won't take credit cards because of how much it cost them and in the case of some of their antique or farm vehicle sales I think they must lose out. Not that people would probably have any real cover on that stuff from a card, just allows individuals to spread the cost.

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.