Alan Ambrose

Well that's wacky, but congrats on the scientific method. >>> basil plant between the two panes Ah, the plants are *between* the DGU and the single glazing? Well they do do the transpiration thing of course.

@Jilly Possible to give a ball park for your piling? I probably have a similar problem.

Welcome. Built without structural engineers, building control and modern materials and tools I expect. If only our new houses would last 300 years

@craig - I think this is still on topic... PHPP lists glazing components, not so much by supplier as you might expect, but by individual part. So, for instance, there are: Glazing units by Guardian - Climaguard, Saint-Gobain, LX Hausys etc. (Maybe 30 options.) Frames by Aliplast, batimnet, Beijing Milan, Harbin Sayyas, Optiwin etc. (Maybe 250 options.) Which led me to think (maybe wrongly) that most of the suppliers to the UK might be sourcing some standard glazing units and some frame profiles and insulation and then doing their own assembly. Maybe some have their own frame profiles. I know you need quite a bit of volume to get a batch of aluminium profile extruded, so that would support this thought. Is that right about the parts, and industry set-up, or is PHPP just weird that way?

>>> The standing charges are the maximum costs a supplier can charge a customer who has not used any energy. Suppliers can also charge less than the limit for either standing charge or unit rate. So, theoretically, at least, you can be charged less than the cap.

Hmmm interesting - if I understand correctly that means the good window's dew point is ~30C and the bad window ~25C. That is, with outdoors temps at 19C (and the inside of the outside pane approximately the same) you should have condensation in both. But that's assuming that the RH doesn't change inside each window as air moves in and out through heat expansion/contraction. I guess the numbers at say 3-4am (when it's coldest) would be most indicative. When DGUs fail the condensation gathers and generally stays once the seal is broken. Maybe that's what's happening here. In any case, I think the easily available options are either silica gel (and maybe a better seal) or maybe venting the void better. I should say that this isn't my subject though More knowledge people will be along shortly...

I think the standing charge does (at least in theory) pay for the losses caused by the bust suppliers and the fixed charges of running the network. But … in practice the suppliers can set the rates how they like. So a bit like the multiple mobile tariffs, you can choose whether you pay a large fixed fee and a smaller per GB charge for data or a smaller fixed amount and a larger per GB charge. Don’t think it’s any more complicated than that.

Maybe take a look at Agile? I have not done a full analysis but I’m getting an average of 17p.

How airtight do you think the single pane seal is compared between the two windows? Maybe there’s a little cheap battery temp/humidity meter you can put in each one?

This kind of thing? https://store.jdpipes.co.uk/power-ducting/

This the inside of the outer single pane? Maybe just trapped humity when it was installed? Suggest putting some silica gel sachets between the two units - assuming you can get to the space between them.

If it really bothers you, you could get a teenager to 3d print a filler for it ... at a bureau if you want the best result. I think you won't notice it though after about a week.

>>> Black silicone inside it and smooth it over? Then it just looks like a consistent black channel /divider? +1

>>> They aren't allowed to pass on vat to yourself under vat rules. I can see why they are nervous though - their accountants probably drill into them from day 1 that that they have to charge VAT for everything (if they're VAT registered). What box do they tick in their accounting systems? For example: https://www.gov.uk/charge-reclaim-record-vat/when-not-to-charge-vat ... doesn't mention 'selling to self-builders' anywhere.

Can I just check where you are.. - was the extra staircase your architect's solution? - are the mist / curtain options not 'a fire engineered solution'? - can you give the rough cost of each option please? (I may have a similar problem) - I'm surprised the fire curtain is expensive. - is it an option to speak to an actual fire engineer?

Congrats

>>> Would a condensation risk analysis be the way forward It might help - ubakhus.de is fairly self-explanatory. Post the condensation results up here and you'll probably get some more insight. What's the roof build-up? It might not be such a big deal to take off the waterproof layer and install more insulation. Post up the architect's drawing?

Planning may well take longer than your actual build does, so suggest starting the conversation with your LPA asap. If you’re lucky, an informal chat; not so lucky a pre-app with a sketch and a list of materials; unlucky - to get any sense at all you may need to do a full application. You can search for similar passed and failed applications in your area fairly easily and quickly - so I would spend half a day doing that. The quick and reasonably accurate way is to chat to a local planning consultant. You can also get a feel for the speed and accuracy of your LPA from the .gov planning stats listed by LPA.

Re beam size - theoretically depends on roof loading of course (if there is a roof). In actual fact, you’ll find it is all so oversized that you can use whatever works aesthetically / economically / practically given the joints you want to use. Re joints - standard would be mortice and tenon with the tenon on the end of the upright post. You could tenon the rafters into the beam(s) also if you want, or birdsmouth them onto the top of the beam. Pegs are plenty strong - they’re only in shear. You might want padstones under the posts to reduce water damage. There’s a bunch of oak frame books and videos. There can be a bit of subtlety re forming the joints etc but by and large go for it, green oak is fun. As Robin says - we’re not making a clock here. BTW if you use any fixings, you’ll want a4 stainless - the acid in oak destroys standard steel fixings v fast.

This guy is good:

FYI there’s a good comparison between old and new here. He compares his experiences between a new build and a refurb of an older house in a very fair way.

>>> using the three riders of the MCS apocalypse viz; data, physics and algebra Very nice turn of phrase 👏 ouch!

The best indication would be: how does the rest of your house drain rainwater? Also, you might want to do a little soakaway test to see just how permeable your clay is. If there's any sand in it it might just drain fine anyway.

>>> Install a supply for the builders in the garden, but make it robust enough (maybe brick built with a roof) and then run a supply from the meter to the house when the time comes. You can do any of the 3 you mentioned. I'm going for your 2nd option but into a GRP kiosk (see the forum for example). That way you only need the expensive DNO out once. You need a bit of extra room for that obviously. Re your 3rd option. It seems the tools most subbies use these days are battery ones - so it may only be a few big tools, temporary lighting etc that you'll be powering anyway. >>> Also, can the "permanent" supply be put into the house as soon as it is "wind and watertight"? Yes, in fact it'll be installed into an enclosure on one of your outside walls. For that, you only need the bit of wall it'll be permanently installed into. From memory, you need to install the enclosure. Then you call a supplier to install a meter. Then it's your task to have it wired further from there - as and when you're ready. And yes, the DNO prices are steep. Some of the work you can organise yourself, that is the 'contestable' stuff - but that's why you might want to have the DNO do the minimum work.

Chatted to the guy using a PS 1000 today to look for post tension cables in concrete slab. Very clever 'ground penetrating radar' which, I think, uses microwave EM. Goes to 300mm I believe. I assumed GPR was high-tech stuff, but it seems you can rent one of these for <£1K per day.