Onoff

Not what the OP is talking about as he's confirmed above. Again an aside to the thread but on the subject of back box earth terminals, where I've come across the odd one that's damaged I've drilled and fitted a Rivnut and ring crimp Broken screw: Rivnut tool: New earth termination vs old: Rivnut shown here on a loose back box just for clarity:

I think when zinc coated steel is cut, zinc oxide forms. This acts as a protective layer. Only really works on thin sheet edges. Same with a light scratch. Won't work on say the cut end of a galvanised RSJ. Best thing for that is a Zilt stick applied with a porta pack. Most now use so called "cold galv" out of a rattle can. Zinga is very good.

Roll a thin bit of card around the pipe and mark with a Sharpie. That'll give you a dead square cut line. Then use the hacksaw to follow the pen line, rotating the tube as you go. As in you're almost scoring it. Take it easy and the saw will follow the groove when you finally cut the tube.

I've used Illbrück expanding tape instead of Compriband. Seems good.

So the tanking appears to have worked?

I've got a 10mm² SWA running to the charger point. Then a 20mm flexible duct cable tied to the SWA with a Cat-6e in.

Any post tanking update?

You would be amazed / shocked at the shoddy installs by "double glazing" fitters. A lot of the surveyors would under measure the gap so the install flew in. No chasing out etc. Ours got put in with damn great perimeter gaps that weren't foamed or expanding taped. They simply super glued trim over the gap and siliconed. Gradually redoing mine. Where the window is in situ I use Illbrück FM330 expanding foam. Trim removed and gap visible: Finger size gaps: Note no cavity closer either: Lots of little things you can do and it all adds up.

Yep, dry fit any solvent weld assembly first and put an alignment mark on adjoining fittings with a Sharpie. Slap on the solvent weld and as quick as you can fit together and align the marks. Nothing so complex needed here.

I think you're mistaken 😂

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Random site but another option. Solvent weld one of these on the stub pipe:

To me the photos look like you already have a "double female" connector in place on each soil stub coming up. You can see there's a little internal stop that the pipe inserts as far as. In your case, more importantly it stops the connector slipping down. Each appears to then be capped with one of these. These can be simple removed by getting a flat blade screwdriver under the lip and levering up. As an aside I always use a silicone spray or smear of silicone/plumbers grease when assembling this stuff:

Mine in the picture above is old colours, red, yellow,blue,black 10mm². Red sleeved with brown, blue as is, yellow sleeved with green/yellow and black left spare. I'm coming in through the back of the EV charger as coming up into the bottom is just plain fugly imho.

I mulled something like this:

Just run separate SWA and Cat-6e to your EV charger like I am:

Well worth a a watch:

You might also consider running your SWA in oversize ducting. You can then run Cat-5/6 cables etc in smaller ducting within.

Moisture resistant plasterboard is GREEN!

Tanker.

No he didn't say that at all. No offence but you come to this with seemingly zero concept of what is to most a basic understanding of how you mix concrete and the ratios. You're being given good advice. I'd suggest you listen / take it. You risk people ignoring you. "2 x half gates will be more stable Quick sum. All approximate. 45 gallons, 200 litres. Concrete is 2200kg/m3. so 440kg. A big bag of ballast is 800kg. So with cement and water one bag will do 2 barrels, approx. If not quite, then chuck in some rubble. Presumably you will cut the tops off the drums".

I'd think about insulation under the floor, like 150mm min. If you're laying a concrete slab then why not incorporate UFH pipes now even if you never use them? You'll want the walls insulated too. Pointless not too. At that size I'd have put a trench in with soil & water pipes coming up through the slab as future proofing. Decide on your plan where you might later on want a WC / shower room.

I had a Vaillant boiler in a rental with BG's top cover package for years. It was annually serviced by them along with multiple call outs and failures along the way. Not once did any of the engineers mention there was no mag filter fitted or recommend doing so. It got to the point different BG engineers were saying different things. One would order parts then another turn up to fit them saying they were the wrong ones. Another did suggest a power flush might work. I got so fed up I outed BG and employed a family friend to fit a new boiler a lot cheaper than BG. He did attempt to power flush the old system first to cure the old boiler but to no avail. At the outset he said he'd attempt it but it was unlikely to do much. Think he charged around £300 for the flush. He did add cleaner & leave the apprentice there all day with the flush rig running saying he wanted to see "clear water" running out of it before he called yay or nay on the boiler. Sure he said modern boilers have quite a small heat exchanger that's prone to blocking which is why the system must be kept clean and have inhibitors in it. Something too about, again modern,heat exchanger materials being prone to corroding / blocking.

The small 20mm ducts are for Cat-6e cables for the EV charger, PV, gate intercom, CCTV etc. I'll use a shop vac to suck/blow draw strings through them.