saveasteading

Make it so. Or use perforated duct. It doesn't need to be twin wall.

And yet the one i bought with the kiosk was white on the long leg and red on the short leg. It was too narrow for the big cable so I used a bigger black pipe without issues.

That's a very good point. But assuming all the ground is the same then the trench below the box should act as a soakaway as fast as it enters. At worst, the cable ends are well clear of such water and the box to base is not sealed so it would run out.

I mean that the cable comes down the pole into the ground, so they need a hole there. Then underground either alone or in a duct. Then at the box again it has to emerge from the ground and go through your hockey stick. In my eyes your case it is only 3 ft. Take away the hole at the pole leaves 18"? Leave hockey stick expose, another 1ft gone. So has a negligible trench so doesn't need a duct. But if you had a bit handy they could drape it over the cable if they wanted to.

A tactical withdrawal is preferable to suffering a massacre. Well done General.

No. If the box and pole were 20m apart then they would need an exposed pit at each. In your case they join so it is all pit.

Feel even better about it, as you are still overthinking. What comes next? Blockwork? As @nodsays, a bricklayer (you in this case) will use a string line and smooth that line out, and up. Relax, work out what level your first block goes at, and move on. If there is a high spot, you could regard that as your new datum and lift the building a few mm.

The point being that concrete is hard work, the workers are busy with what they do best, and not esp skilled with lasers etc. Ie do the precision at leisure. 10mm either way is absolutely fine though and better low than high. 15mm is probably typical of decent work.

For future reference, I tended to either bang pegs in the bottom and mark depth with a nail. In clay, knock nails or bars in the sides at finished level. Very formally for precision ( big structures) we would have T profiles along the side at say 2m above finished level and a 'traveller' a T that we placed on the concrete and lined up with the profiles by eye. A laser can replace this if used skilfully. Big IF. Hence the nails.

It's OK. I've seen very much worse. Lasers aren't always accurate and are only used approximately in trench footings. Successive processes get more accurate but For perspective: the published tolerances in timber buildings are plus/minus 10mm.

what you show was state of the art, but about 30 years ago. It's thin, irregular, and gappy. And there are old bridges from the room through the timbers to outside. Its a matter of balancing cost and benefit. Youll find much more previous dicsussion on here. I think, 1. keep what is there but straighten it out, and add an extra thickness... how much would it take? 20mm? PIR is best for insulation. Or replace what is there with PIR. BUT it is tricky to fit tight so maybe you'd end up pushing in the fibreglass again, or a boarded version. Then an insulating inner layer over the surface would kill the cold bridging.

I don't think so. It's great to think it through. You are now the world expert in this issue.

If it can get wet or is exposed to insects, then use treated timber. I suppose you could immerse your untreated timber in preservative, so that it goes into the end pores. But a tin of that is expensive itself.

Jam all the gaps with PIR and squeeze in foam, as above. 20mm will make a big difference, and the extra heat loss will be a few £ a year. 10mm tolerances are acceptable in house specifications... prob no blame.

An alternative. Use a screed mix, which is sharp sand and cement, low water content and probably fibres. You can barrow it for a few hours , while tamping it in place. I'd still recommend using professionals...but the pressures are much reduced. This also depends on the design as it isn't structural concrete, but fine for most domestic situations.

I've been a contractor for decades and seen hundreds of big slabs going in. I have seen enough to know that your plan worries me. I will step in to help or for interest in most processes but have always kept out of the way during this because it is skilled and brutal at the same time. Good points made above. eg the pipe is full of stone and is stupidly heavy as well as kicking around. The guy on it is usually a super-fit 30 year old. Consider buying 3 barrows and hiring 3 labourers instead of pumping.... you win control too and can compact and level as you go. You will need scaffold boards to move around on. Washdown at the end is a horrible, filthy job, especially the inside and outside of the pump pipe. I mentioned this post to my daughter (Contractor , Project Manager, Architect). Her jaw dropped and she immediately thought of the risks. One she added was how well your insulation layer is covered...… the membrane must be intact and completely sealed at all laps, otherwise the concrete forces through and the insulation floats to the top carrying your reinforcement with it. I have seen this happen. Check your laps and tape as necessary one more time. BUT seriously consider postponing this and getting a professional gang to do it.

This is a standard product and option, but more often for a screed than a structural slab. By default anyone offering a product at a show is not going to suggest other options. Tell us more about your intended project and get more detailed advice.

I'm panicking for you. That concrete will come faster than you can level it. Then it's too wet to walk on for a few hours for any precise work....until it's not, at which stage it is getting hard and difficult to improve. Cracking isn't your biggest worry. Di not allow any extra water in the mix. It will crack jaggedly at the doors but it doesn't matter.... or you lay a bit of hardboard in the surface to make it crack there. As above, fix level markers to the walls and also in the middles they can come out again. How many loads? 2 I guess. Give yourself at least an hour between them, perhaps 2. A shovel each and a bull float. Polythene over the lot once you can walk on it.

I can't comment on how professional they are or their product. Please insist on seeing their PI insurance ASAP. If you proceed then I would hope the the BCO reads the whole proposal to ensure that they have considered what is appropriate for the whole construction. I have an assumption that the company starts with sales , then moves to feasibility of their product, then proof that their product works. An independent SE or Architect may have other matters to consider and perhaps another solution. I've spoken to a few screw piles suppliers at trade exhibitions. Some are professional and understand their product and appropriate uses. Others were simply agents and were remarkably ignorant on technical matters. a wanut can grow to 18m and the trunk will be wide too and reach your wall position.. Clay ground will shrink and expand a lot. so I'm guessing piles or footings will be about 2m deep, maybe more. Or 1m if the tree is gone. The existing house may be affected too. My starting point is to demolish the existing building, remove the tree, use conventional concrete strip footings which any local builder can do. Probably cheaper too, and certainly easier and cheaper to insure your house , and to sell in the future. Screw piles and sips. The result of attending a self-build exhibition by any chance? I am NOT against either btw, just a cynic, and you have asked for opinions here.

That is your imagination or selective viewing, or repeating what the competition are saying. Perhaps you disagree with what you hear and regard it is propaganda. I've heard plenty such reports and programmes. Try BBC2 and Radio 4 for more nuance aimed at seekers of information rather than entertainment.

I think we know that answer. The number of voters, encouraged by the locals with big money. Plus, as a Scot living in the far SE I am constantly aware that the majority here have not travelled much north of Kings Cross, and have minimal interest. "Scotland" is mentioned in the ignorant London press as a minor place. eg Lord and Lady Muck have a house in Mayfair and another in Scotland. This is more a matter of ignorance and educational lack, than any malice, and I know that 'the Midlands', 'The North' etc have it nearly as bad. On a positive note. In the event of any political breakdown, Scotland will be self contained in energy or could add 1p to every kW that crosses the border. Spain has many thousands of turbines on the inland hilltop ranges. In my opinion it improves the view, which can be very beige and bland, unlike Scotland's scenery. That is the language of the deniers, which I know you are not. But man-made disasters will still be disasters, and additional to the natural ones which will keep coming whatever. 10 years ago 'global warming' was seen as a myth by many who now accept it as if they were always aware. They were, back then, fed misinformation by the powers that wanted the status quo. The change of view is due to gentle persuasion by those of us who care.

quite so. Aren't we boring writing middle of the road stuff. Those who want to read about how awful everything is / will be can find it in their own chosen source of information. The 'middle of the road' news suppliers are ridiculed by both extremes, and equally by the powers who provide their chosen version of news. Being personal for a moment. I do like the BBC news, TV and radio, and their website. That is where I go for real information. Perhaps it is cautious at times but otherwise they get sued or shut down, and certainly bullied. The unspoken stuff will be there too, nuanced perhaps, but not ignored. I do look at extreme views for information, and I do worry that the average punters ( or the ones we hear from) identify with their chosen extremes. To much 'journalism' is just cut and pasted from press releases. That's verging too close to politics perhaps, for BH, except that we major in pragmatic sustainability, but I welcome others' input as to where balanced information can be found.

If you can advise on that we can add to the advice, or ask your SE. Just a thought. It is an SE working for you I hope, not one working for a screw pile supplier? With the tree gone and the winter to recover, you may only need conventional 1m strip footings.

I might read it later, without prejudice, other than it being fairly clear from your summary that you agree with it's premise., which might just be that we don't need more wind farms. So I am prejudiced already I feel. Hence I'm guessing also that the author isn't much worried about our gas and oil being cut off. My philosophy is to aim for "nett much less" , as zero is impossible except in a disastrous return to the stone age, and because the major powers like things as they are. My garden has enough free compost to save buying 10 bags a year, and veg from june to september. I already own the petrol and battery powered equipment, so that doesn't count as a cost. I put on a jumper before turning on the heating. That is approaching nett zero isn't it?

Tree away. You may still need deepish foundations though because the tree will no longer be drinking the groundwater and the roots will rot. My pragmatic advice is to cut it down ASAP and let the ground recover. It depends on the type of tree and the type of ground.