Mr Punter

Hi @D Walter and welcome. You are obviously a fair way into the build now. How did you hear about the ICF system? Is this your first self build? Did you use Surrey Home to do the build or just supply the ICF? It is a bit odd that I have never heard of the system before and it seems to be a one man band operating from a serviced office. Interesting to hear about the blow-out. I had similar with another ICF brand on a basement. I think my men had left out a tie. Fortunately it was on the outside and we were able to shore it between the wall and the excavation and we only lost about a metre of concrete and the bulge in the wall was hidden once back-filled.. It happens frequently but it is a bit nerve-wracking.

When / if you sell, you may need to pay the insurance premium for the buyer.

I think if the concrete had been better detailed and executed it would have looked OK, but that is very difficult and expensive to achieve. A feature wall or corridor internally may have worked better. The ceilings looked like those at @pocster's place! The finish from the shuttering was poor. I am not sure if the formwork contractor had used the system before but I was not impressed with them. I have seen some excellent concrete work. They could have had timber plank pattern or exposed aggregate. A fail.

It is up to the supplier to know what size window they are able to supply. It should function correctly. If it went in with a twist it needs reinstalling.

Yes SIG are excellent and deal with many different systems and will take full design responsibility. You can deal with accredited contractors and get a proper design by and install at reduced risk (although at a price - but at least it will work).

I think you need a proper drawing of this detail. TBH you need a proper professional design and spec for the whole roof. Don't try and design it yourself.

OK does the current approval have a condition saying something like "..the development be carried out in accordance with the approved plans.."? If so, you can do an application for variation of this condition and the fee is £34 for a householder. Just submit the revised plans with the application, showing the new roof covering and a covering letter explaining that this is the only change and the reasons it should be approved.

Those industrial pan scourers should be OK. https://www.ebay.co.uk/itm/Large-Stainless-Steel-Scourer-Tough-Wire-Cleaning-Pads-Washing-Up-Scrubbers-10pk/302825614647

Did you have a planning condition on materials samples (to be submitted and approved etc)? If the only thing changed is the roof tiles - not the solar panel type / colour profile etc - can you not resubmit the new proposed tile?

That cat from Saudi?

I would leave it a couple of weeks, provided there is no way they can chew their way out. If you still hear them it may be time for some bait.

Yes, mortar. They recommend non-shrink but really any will probably be OK. Make it fairly sloppy and gun it in with a pointing gun.

Is the cavity vermin proof all round?

I am not sure I quite get you but if it is not level you will need to pack it up completely level. If you pack under the DPC you will later be able to gun in some mortar between the packers. Do this from both sides to fill any voids. If it is out of line you will either need to do a redesign on the frame or you may be able to overhang the soleplate by a small amount.

You could have 15mm plasterboard, 25mm service cavity, vcl, 140mm timber frame filled with 130mm pir (90 + 40), 10mm sheathing, 50mm cavity and either render board system (15mm) or brickwork (100mm). With the render board system you may be able to reduce the 50mm cavity to 25mm, so for render board you will have 230-255mm and with brick it is 340mm. I think this gives a u-value of about .19 but sometimes it depends who does the calcs and what flavour pir. I think you can claim the service cavity as a low e gap.

Small children getting their heads between the wires is the risk.

Most of the plastic 450 chambers have inlets at 90 deg to the main channel. The outlet has to be from the main channel but you can put a 45 deg bend on it and still rod OK. You can also put a 45 on the inlets, so lots of flexibility.

I have RK doors x 8 on a development. Cost a fortune but look OK.

The new IC will be fine in terms of inlet numbers and angles. It is important to check invert levels but the connections from the utils and kitchen will be above the main sewer pipe and the connection from the new IC to the sewer will either be at the same level or on top if it is a saddle onto a larger pipe.

Without seeing the rest of the front elevation it is difficult to suggest. A timber finish can often bridge between traditional and modern. The big vertical handle seems to be what planners consider "contemporary" but they can be a bit clueless. Also consider if you are having a letterplate and if so where. Do you want an external lever handle? Do you need natural light? Is there to be a bell push / entryphone? As a general point it is very good to have a canopy to protect from rain.

https://www.jameshardie.co.uk/product/accessories-and-tools-cladding/ the ventilation stuff

I have used the perforated metal stuff from James Hardie. They do a bottom profile which gives a kick to the first row of cladding or slate and a l shaped top profile.

We have sliding door wardrobes and the end doors have soft close which fits to the top of the door. I can see that @nod is a dab hand with the metal stud!

Petrol masonry saw?

I think @Dreadnaught is about right with his thoughts. The main things affecting £/m2 sale prices and desirability are 1. Location 2. Kerb appeal You cannot do anything about the location if you already have the plot but the front elevation is what people will see on Rightmove so make sure it looks right. For the space you have downstairs: open plan kitchen living dining (with divider if pos), downstairs WC / utility (a utility with a WC), study / desk area. upstairs: 3 beds, 1 bathroom (bath with shower screen), en suite shower (large shower). Wall space for storage in each room. Plan the layout very carefully so you don't have wasted space. Floor coverings: Hard flooring downstairs - same throughout looks sleek. Carpets to stairs and bedrooms. Luxury vinyl tile to bathrooms. Gas CH. Don't bother with UFCH unless you have tiled ground floor. Combi boiler. No home automation.