Mr Punter

Glulam will be deeper. Price up in both.

Looks good for haunching up kerbs etc. Tossers.

They look good. I guess that at about £5 each, they won't feature for most plumbers or builders, but may work for high end projects and self build. I think tracpipe gas pipe is a bit like this, but it has a plastic outer sheath.

+1 for a couple of dMEV fans. You could also have humidity trickle vents or through wall vents for fresh air. Get rid of the tumble dryer and use a decent dehumidifier with plumbed in condense. Put a drying rack or rail in the same room / cupboard as the dehumidifier.

Yes. Don't have plasterboard as a strip either side and waistbands in the middle. Make the plasterboard L-shaped or e-shaped if you can and you won't get cracks on the joints.

This old garden wall had ivy growing in / on it. It did not do it much good!

With some of the Rationel frames you can couple them in a stack. Have a look at their install literature or ask their tech dept.

Fit a shower pump into the cylinder cupboard. Single impeller if your cold supply is mains pressure, twin impeller if it is a cold water tank. The negative head ones have a small air chamber that pressurises when the flow stops so the pump will be ready primed.

You seem keen to get a report from a SE. Most will deal with this competently. Let us know what they say.

With these sorts of issues I can understand why this system has not been adopted by the housebuilders.

Smell is very difficult to establish and prove. Actual moisture and mould can be measured and photographed. Have you had anyone else in to verify the smell, like a mate or your partner? If it is really obviously bad you should go back to the housebuilder and register it as an official issue, stating that x people have also noticed it.

Well the SCC looks like it saved a lot of work. Was it expensive? Is the next pour to a different level?

The stainless steel ones seem pretty good. I had one fitted and it stopped the rats and has not caused blockages. Some of them have a mechanism that allows them to be fitted fairly deep in an inspection chamber.

We put standing seam on a roof and the customer had solar added. The were fixed by brackets that clamped onto the standing seams. The roof actually had a slight fall to north but it still worked fine. The standing seam was Kalzip type.

Agree with @Spinny if the rule was not around until 2023 your steel was already in. Point this out to BC. You can't comply with rules that did not exist at the time.