saveasteading

But you are the PM and made a considered decision I assume. I have read on here of 'professionals' deliberately cutting pir well short of rafters and foaming it in place. My gut feeling is that this is wrong, perhaps emphasised by how wrong it is to insulate whole roofs with foam. What a good point. I can't recall ever seeing a spec that included expanding foam. Even the much lauded Illbruck,

Ii it any better than an air pocket? If the gap is 2mm or less, leave it. If 2 to 10mm, insert a sliver. If over 10mm , try harder. I would like to make the use of foam for anything forbidden unless agreed by the project manager in writing. It has its uses but is usually for bodges.

I don't think that matters. The aluminium does nothing for insulation levels. Tiny gaps don't matter really. They are closed air pockets. Screed getting through will harm the insulation properties....and floating pir is a disaster.. hence the top poly. The question....yes add the 50mm in pir. Eps is half the benefit, perhaps more than that if on the bottom.

It will be better but not a lot. The amount of air pumped will soon exceed any affected by the cold surfaces. I did have a job where the original architect put solar panels next to a north facing wall though.

One of Parkinson's laws is that everyone chips in on an easy subject. Whatever fixings are used here no one will die. Roll on page 3.

I used to use and dpecify concrete screws but don't now. The hole has to be exactly right to a fraction of a mm or the thread won't bite properly. So the exact bit, without hitting obstructions. I'd much rather use a quality plug and my own choice of screw. It's only a wooden shelf. Hence such a long discussion.

...and it is easy to blame only them. It's everybody's responsibility. Some will take it, others will live for the day. Some care for those downsteam, others only themselves. Does the same apply for recycling? People range in attitude from fly-tippers, through chucking it all in the bin, to thorough recycling, to not buying disposable packaging. I say we should all dispose of our water thoughtfully*, whether the law requires it or not. * which requires education and opportunity. Or might not. Eg the Paris Olympics. The Seine was more dangerous after rain.

Have a friendly chat with the contact name. Explain that vans are welcome to park in your drive and materials can be stored too. Will you be scraping back the gravel or they? Will you be needing to use the drive during the works? They have prob allowed 3 days. Prepare, do, clear. Ask if that helps and they can reduce the sum?

It isn't easy, and an excavator needs space and stability. Then the muck has to sit somewhere. Hence it needs a properly cordoned off space for the work and the vans. Even if it was a smallish hand dug pit, the workers need protection. You can always ask, but these are fairly standard cost levels. We just had something similar. They closed the whole road. The workers had abuse and sticks thrown at them. Apart from needing road reinstatement, the scope was similar and the cost. But ask if it can be reduced because.... find some reason.

I might take a chance. I cannot advise you to. You must get an SE look at it, even informally walking round with you. The tree is long past being relevant I think. Any recent holes in the ground nearby to see what the ground is? But a local SE will know anyway.

Then you are blocking the ditch. A bad thing. Am I misunderstanding?

Sips is trendy. Sips is limiting re geometry. Use what the local builders are happy with, whether timber frame or masonry. Or buy in a timber frame as a kit. TF is not expensive if kept simple.

Once you have had the word used, you need to advise insurers for ever, so it's a good thing the term is not used here. As the structure is OK, it probably isn't. You have a small chance of a big problem. Ultra local moisture effects are unlikely......the slab is protected by walls and footings. A large chance of a small problem. Tell us more about the hollow sound. Is it when walking, or tapping? Could there be a top screed that is loose after pipes were cut in?

It is meant to cling to surfaces to allow bacteria to do their stuff. As you say, we don't know the circumstances. But the cover levels are +/- a metre, so it all seems strange. Agree re using French drains rather than crates for sewage, but maybe this is for storm retention.....can't tell.

Subsidence seems the likeliest thing. Ground shrinkage would be more general than just that corner. It might only be the slab, not foundations. If it is clay shrinkage then it shoild tecover over the winter Are there any cracks in walls, inside or out?

All the worthy terms get stolen and abused by the developers. My main hate is " value engineering". It used to mean elegant, efficient construction. Then the QS industry turned it into missing things out and cutting corners. So I don't use the term any longer. My own prejudjce on "eco" is of experimental houses, spending other people's money on nth degree of detail and anything trendy. Wind turbines, ground source, off-site, green roofs, solar regardless of circumstances.

This discussion also took place a few days ago. My summary was: If you know exactly what you are doing, the building is conventional, and you accept risk. Building Notice, and you can start more quickly. Otherwise, Full Plans.

I like that. It should save cost, and take up much less space. There used to be a standard EU design but perhaps that is superseded now, or simply ignored. Plus Klargester is part of Kingspan and I wouldn’t give them £1 of my money. Agreed. I intend to look up all the Kingspan brands, also St Gobain (who have sold off celotex), and avoiding them.

The design is a mess. Sorry. Can you show more of the drawing? Digesters have waste in one end and out the other, not as shown. Non return valve?? Are the crates to hold flood water then it drains away, or as a soakaway?

That said..... I've just finished designing our own. The drainage field size is crazily large in my opinion. The regulations only allow a 20% reduction as compared to a septic tank outflow. In reality the bco may accept a soakaway. With a bit of gravel on the bottom that would work nicely....say I but it isn't my decision. FYI A Structural Engineer generally studied and got a degree in Civil Engineering. Or Civil and Structural. Thereafter there is too much to know and it is best to choose one then later take the Professional Exams. So your SE may well be a little behind on treatment tanks.....understandably as the regs are a mess. It is tempting though to go with the flow as an "SE" though, as a differentiator from groundworkers who call themselves civil engineers. As above..choose an air bubble make. I am specifying Marsh. You need a sampling chamber too. Document H, page 45 and others, if you are up for it.

The digester must have its own soakaway or drainage field. This is so that any nasty stuff that makes it through will cling to the hardcore or gravel surface and the digestion be completed. Otherwise the mucky stuff percolates down and may contaminate the aquifer or other waters.

As discussed elsewhere I've recently been knocking up such a wall. What I found was that the osb is very fragile at the perimeter, where a squint screw or a little twist will break it. But on the central stud they fix snugly, as they do on noggins and any other non perimeter surface. Then it is stiff and think the perimeter ones work well enough in shear. Glad it's all ok. It's the danger of misinterpreting a photo. There are a few options to keep the house standing. Will you keep us informed?

A worrying thought. That stud wall would need 2 more studs to be at 600cc. An extra £6. And it should have noggins. I don't think a designer or the developer decided that. Was this subbed to a little builder who put 4 studs in the wall and 2 in the van? How often do I see someone on Facebook selling a pile of stud? Why do they have it? Where did it come from?

Can you look in manholes in either direction to measure the pipe depths?