Roundtuit

Looks like a natural plant response to some sort of pest grazing damage. It's probably superficial and will scrape off when you wash them. I'm going to say Capsids, but mainly 'cos I like the word. (Capsids...)

Do you happen to have a 'before' photo of the flat roof side? It looks a bit like they've built the new roof on top of the old one, and hence the 'difficulties' at the ridge. No easy answers I suspect...

Sorry, I don't know enough about piling to add anything useful, but piles are usually designed to transfer load vertically to load-bearing strata. What you appear to have is a plot that's sliding down hill, which perhaps may potentially put lateral stress on the piles. Personally, I think your SE should be designing the foundations and then you can put the approved design out to tender.

I don't want to put a downer on your creativity, but it sounds like finding out what the roof covering is is the least of your challenges! If you haven't already, I'd perhaps seek some pre-application advice from your LPA before you cut any holes 😉

I doubt it. As pointed out above, its a retaining wall so you'll always have moisture coming through from the back. It will be ok if you're happy to give it a scrape off and repaint on a regular basis though. I used to do the concrete blocks in a light-well every year, but that was only an hours job...

Yep. An after-market addition when the client realised that the 'architect's vision' seriously spoiled a game of 'Mr Wobbly Hides His Helmet'...

Personally, I'd part company with the architect and QS with immediate effect, and you can manage without either of them. Self-building is hard, and it's reassuring to have a professional to hold your hand. If they're leading you down the garden path however, they need a wake-up call. All credit to you for pushing back!

What's it made out of? Stone, or concrete/render made to look like stone? I think I'd just pressure-wash it and repair the section that's moved a bit, and maybe change the coping stones. To use brick slips I suspect you'll have to render first to get a flat surface, and it doesn't really seem worth the hassle.

I think I'd invest in airtightness test before making a decision. It will help you identify where the leaky bits are and decide whether new windows will make enough improvement. Thinking about it, unless you're fitting mvhr, you'll have to have trickle vents, so there will maybe be limited airtightness benefit...

Why? Is the ashp set to maintain a full tank of hot water 24/7?

Even my lawn is dry enough to tile now. 95% RH can't be right can it? Have you got plastering drying out too?

Our scaffolders were fine putting the stuff up, but getting down again took forever. I ended up dropping some of it myself out of frustration (had to 'loose' a couple of bits that got bent...) and leave it all neatly ready for collection. I expected they'd be pi$$ed off that I'd messed with their gear, but they actually knocked a bit off the invoice as I'd done it myself!

Really? That cabinet should have been a wine chiller or beer fridge, or an overflow wine chiller or beer fridge. And why would you want to play such a cruel trick on a kitchen fitter? Plumber maybe...

Interesting question! Depends on how significant the change is. We had a timber frame. If I wanted to move a doorway 400mm, it was sucking of teeth and back to the drawing board. If they'd somehow managed to omit an internal doorway in the frame, it was sorted on site same day... I think honest and open communication on both sides is key. Your builder needs to be upfront about the implications for him/her (including the impact on their other commitments), and then you can decide whether the change is worth the cost.

We've got Rationel alu-clad 3g windows. On balance, I'm happy with them; timber and cladding seems fine 4+ yrs in. We have had a window mechanism fail however, and are now trying to get a door backset replaced on warranty. I'm disappointed we've had some failures, but they do seem to be honouring the warranty (in mega slow-time, but some of that could be agent)

There are flue systems that can also supply an external air feed, but I expect they're expensive. Anyone heard of running two flue pipes up the chimney to use one for an air feed? You'd have to get some separation at the top end obviously.

That is a bargain. I bought one two years ago at £299 and I thought that was a good price...

Unlikely to be anything serious I suspect. Can you get up above it in the loft and have a look? It might be plasterboard over old lath and plaster where the fixings have failed. Does it move if you push up on it? Might just need some additional screws, a smear of caulk and a coat of paint.

You're not getting a laughing emoji for that...

Fantastic! Keep picking them young though or they'll soon get away from you.

Looks like your window could have been a inch taller! I expect they measured the old ones and didn't account for the difference in cill profiles. Just trim back the foam and packers and point-up the gap (looks like you have a bit of pointing to do on the stonework anyway). I wouldn't expect to see anything significant between the glazing tbh.

As above.... you'll never achieve 'perfect information', but if you do, the rest of the world will f**k it up for you before you get it built. Take your best guess, and start building something ffs!

It could just be old lath and plaster sagging, but as above... need a bit more to go on please!

I'm not disagreeing, just interested in discussing the theory... I thought that the reason for a non return valve (eg on a garden tap that can be attached to a hose) or an a-type air gap (toilet cisterns) was to stop anything unpleasant being sucked back into the mains system if, for example, the fire brigade tapped into a hydrant up the road and caused reverse pressure?

38mm sounds a bit tight for plasterboarding tbh; doesn't give you much room for screw placement at joints. It also sound a bit light-weight for timber cladding, but you might be ok; you can use double battens at board ends. Thinking about it... you could also double-up for plasterboard joints, but that's a lot of extra faff.