Insulating from the outside: wood fibre vs rockwool vs perforated polystyrene

[Garald]

1 hour ago, Mike said:

At least one - https://www.propassif.fr/. But the database in international - https://database.passivehouse.com/en/components/list/ventilation_small? - and Efficiency Ratio is the key number.

 

I see a lot of units. What is really important (beyond getting a quiet unit with a high efficiency rate, I know) is to find a unit that can be installed at all, and an installer who can install it! Remember that this is an old house. There are the conduits for the PIV (not extremely broad, and only one "mouth" per floor) and the old chimney conduits. I think the installation will be easy in the ground floor, thanks to a false ceiling, but I'm not sure of how it would be done in the other floors.

 

(I take the 'heart' of the unit could go in the garage, which is inside the house?)

 

So really what I want is good MVHR installer who is technically wily and also frank about what can and cannot be done.

[Mike]

24 minutes ago, Garald said:

(I take the 'heart' of the unit could go in the garage, which is inside the house?)

Yes, ideally in an insulated cupboard.

 

26 minutes ago, Garald said:

the old chimney conduits.

If you can get some insulated duct through them, and if the adjacent flues are dead, then it's a possibility - preferably the intake down one and the exhaust up another, so that the air from the latter doesn't contaminate the former. Though if connecting to a unit in the garage you'd ideally you'd take them through the garage wall / roof.

 

[SteamyTea]

8 hours ago, Mike said:

The French new-build standard (q4) requires  ≤ 0.6 m3/h.m² at 4pa

Thanks for that info.  Not that I am allowed to more to France easily any more.

[Garald]

5 hours ago, Mike said:

Yes, ideally in an insulated cupboard.

 

If you can get some insulated duct through them, and if the adjacent flues are dead, then it's a possibility - preferably the intake down one and the exhaust up another, so that the air from the latter doesn't contaminate the former. Though if connecting to a unit in the garage you'd ideally you'd take them through the garage wall / roof.

 

 

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