Garald

Not sure where I'd drop those ducts. Perhaps the simplest thing is to have two systems - one for the right-hand of the first floor and possibly the right hand of the attic, housed in that empty hidden space in the attic, and the other one on the left side of the house. At the same time, it seems a bit of a waste not to use the garage at all - that would be the natural place for a potentially noisy machine.

A question has been going around my mind for some time: what about Passivhaus in *other* highlands? Say, in the Andes? Some of the conditions are similar (it gets chilly up there) but others are rather different: - tropical latitude - the colder season is also the one with clear skies and lots of sunlight (and UV) - ... which brings us to our next point: considerably thinner air There's a smattering of news about the matter (people are experimenting with Trombe walls, for instance) and a tiny handful of builders ("ours is the first Passivhaus project in the country" is more dispiriting than anything else) but I don't know of a good source of information.

Right. The guy who did the renovation said that he's using 'the old chimney ducts' for an extractor that was noisy and turned out to be pointless (just had it turned off) - I was never sure what he had in mind; the ducts of a chimney that went the way of the dodo? I suspect a bit of the red space on the left may already be used in part for the PIV ducts - the attic PIV outlet is just outside it, in front of the leftmost part of the computer desk in the above drawing. But yes, I think it's mostly empty space (which could not be used otherwise; I had no desire to crouch while using the toilet, as would have had to be the case if the toilet had been set further back). I also think the red space on the top right is empty. It's right above the kitchen - I imagine what lies under it must be used as ducts for the extractor above the stove. But how could it be connected to the rest of the ventilation system? Would there be a different heat exchanger here?

While we wait for @Mike to respond to nudging, here are some photos of what I've been up to, with a friend's help (meaning he did a lot of it). After a lot of trying, we managed to stick a stopper made out of sheep's wool up the bedroom chimney. Now I wonder whether I should get an even bigger stopper, to make sure there are no airgaps. I did some weatherstripping a couple of days ago. (I had already done plenty of weatherstripping some months ago, but one has to be thorough - the airtightness testers noticed every missing bit, and even parts where the weatherstripping had been deformed. This is an inside door leading to the garage.) My visiting friend was particularly neat when caulking the staircases with acrylic. He let me do two steps. A bit of cork and some acrylic was enough here. All of this is of course hidden from view ordinarily. Now for the major gap in the attic ceiling (hidden between two rafters): This was a very big hole (about 14cm by 8cm)! It's a good thing the roof insulation is mostly rockwool - imagine if it had been fiberglass or some other severe irritant. I put together a made-to-measure stopper made out of two differently sized cork layers, 2cm thick each, and then my visitor sealed it with acrylic.

I thought: should I say « carpenter » or « joiner » here? The French word is « menuisier « . A menuisier takes care of small wooden things rather than large wooden beams; he also takes care of other finicky stuff, such as windows.

@Mike Considered yourself nudged. I've already implemented the suggestions for the ground floor (mainly further weatherstripping); a carpenter came to fix the leaky first-floor window today, and he seems to have done a good job. An electrician will come in a few hours to look at all those electrical fixtures in the attic.

This is going to be awkward: I don't think it's going to work unless I either remove the cork panels first (no thanks) or drill holes at the top of the door (and take the door off its hinges, which I also don't want to do).

Here are some examples of graphite- and non-graphite-coated balls: https://www.leroymerlin.fr/produits/materiaux/isolation/plaque-polystyrene/polystyrene-expanse/250-litres-billes-de-polystyrene-m1-anti-feu-isolation-poly-xpansion-85633522.html https://www.materiaux-naturels.fr/produit-decl/5798-billes-isolantes-polystyrene-graphitees-200-litres The problem of graphite-coated balls is that they catch fire quickly (within a metal door, would that be a non-issue or a death trap?) The other issue is that one apparently needs some sort of gun to blow them in, though that doesn't seem to be necessarily all that every expensive: https://www.materiaux-naturels.fr/produit/1238-pistolet-propulseur-de-billes-isolantes I guess the manically consistent choice would be to blow in cork bits. The cork bits from materiaux-naturels seem too large (the "pistolet" works only with spheres up diameter up to 2mm), and even those from here may be: https://www.natureliege.fr/granulat/6-granulat-de-liege-naturel-en-vrac-pour-l-isolation-thermique-et-acoustique.html#/268-epaisseur-2_a_5mm/696-conditionnement-sac_de_100l Of course cork gives only 3/4 the insulation of polystyrene, but it's probably wiser to have a bag of cork rather than a bag of polystyrene in the garage.

Oh, this is a metal door leading directly to the (now rather cold) courtyard. That's why I am so obsessed with insulating it well! The room used to be a laundry - now it's my parents' studio when they visit. Oh, I've got plenty of adhesive-backed cork. As I said, there's a 2cm-thick layer and then a 1cm-thick layer on the door by now. I'm not sure I can put on any more without making the door even odder-looking and hard to close. That's why I'm wondering what to put inside the door. Yes. Someone came with a fan door last week and pointed out some weak spots in the weather-stripping - just fixed it I think. I've also had to pare down the cork a bit with a utility knife to make sure the door closes well and the cork doesn't come off.

Right, if I knew any carpentry, I might have considered PIR, except putting in PIR is unkind to the fireman who comes to drag out one’s charred remains. Also, bare cork does not look that bad if you are not my girlfriend. Bare anything else is not really an option.

3cm-thick cork is already not bad, but my girlfriend hates it. What I’m proposing is meant to complement that, though, not replace it.

Wait. Are well-insulated exterior doors affordable elsewhere? Are 4k eur doors a France-only thing?

Right - wouldn’t I be better off filling the door with wood shavings or cat litter?

A well-insulated outside security door costs 4K eur over here.

Yes, « core» or « door ». Sorry.

As some of you may remember, I insulated a hollow external metal door some time ago by pasting 3cm-thick cork on it. I just removed an ugly curtain rod that had been attached to the door some time ago (long story). I was about to cover the bit that just got uncovered with more cork, but I thought: why not drill a hole in the metal and fill the cork with tiny polystyrene balls (say) and then cover the hole with cork? Is this the sort of thing that an individual with essentially no DIY skills (and a regular Bosch drill) can do? How would I get the tiny polystyrene balls in? (And can one just walk to a store and ask "please give me a bag of tiny polystyrene balls for insulation"?) Also, is there much of a point in doing that? How much good would it do, given that the polystyrene would still be surrounded by conducting material? (Ignore the bit of moth-eaten alpaca sweater on the handle - I'll find a neater way of cutting off that thermal bridge.) Suggestions of things less dangerous than polystyrene in case of fire are also welcome.

OK, I will gladly nudge you.

People in France (well, Paris, or the northern half of France perhaps) are generally of the opinion that AC moves germs around and around (with a seasoning of things that grow in ducts or filters, but that's just improper maintenance). Might make sense in some contexts (restaurants, or other crowded spaces).

Wait, so it's recyling air, right? (Or maybe it need not if you also have MVHR?) Don't the same health concerns (which may or may not be reasonable) as for AC apply?

That’s remarkable. The ones advertised around here tend to be between 2 and 3 (with some saying that 3 is not really attained in practice). Actually (and this shows I am not talking from actual experience) to what temperature does an A2A generally heat air?

I thought the COP of A2A, while improving, is still clearly below that of A2W, and so it's more of an option for places where there are about as many air-conditioning days (to the extent that there is such a thing) as heating days? I'd think the set of places in the UK falling under that category is empty (unless you count Gibraltar or something).

Ah, the test people just got back to me. They estimate, informally (I asked), that, if I put all their recommendations into practice, I ought to be able to go from a Q4_{Pa-surf} of 0.98 to one of about 0.7. (a) Does this sound like a reasonable guess? (b) Should I be happy with 0.7? Is that enough for a good double-flux setup? What sort of thing would I have to do to go further down?

Here are the recommendations. As I said - what would be a ballpark guesstimate of how much they will help? suggestions_airtightness.pdf

Just got the actual report. In the end, the final result is not nearly as good as I was made to expect verbally. It is Q4Pa-surf en m3/(h.m2) : 0,98 whereas the objectives are 1 in new build and 1.7 in renovation. Here are the actual measurements: So, in summary, this is an n50 of 4.15, right? And that's pretty mediocre, and what people guessed? Here's their take on the result, but it just shows that local standards are not very demanding. I got a long list of suggestions, which I will post next (it's pretty much the ones I mentioned). I take I should put them all into practice and then shell out for another test? Or what would be an educated guess as to what the effect of putting them into practice would be?

Let me upload the plans here, so that it's clear what we are discussing. Attention, these plans are edited versions of the fake architect's, so they are accurate only to within 10cm or so, and they are also lacking in details that are all-important in this discussion (ducts) - I think she just took some sloppy measures and put them in her CAD software back home. Where I am observing/guessing some ducts are: - current VMI ducts: * fed from the courtyard at ground level * in the ground-floor studio: going above the false ceiling, particularly above the bathroom and kitchen; the output 'mouth' of the VMI is in the studio wall next to them; * in the first floor: behind and above the shower, with the 'mouth' in the corridor next to the shower room * in the second floor: mouth on the short wall on that same side, roughly above the shower - old chimney ducts: bit of a mystery to me, except they obviously have to be close to the two current chimneys (the one in the library, which I could in principle still use, and also the one in the bedroom, which I will never use - the contractor knows that and may already be using part of the ducts) but also possibly to one or two chimneys that no longer exist and whose departed ghosts are non-obvious to me. IVRYHH Isolation plan corrige-1.pdf