Choice & Installation of insulation according to roofs and rooms

[DC]

Hello everybody

I must make a choice to use the insulation material already acquired and what remains to be acquired for the insulation of the roof in different parts of the house. What criteria for doing this?

1. Kitchen (at the back of the house, south-west side) + Bathroom (same as south-east side)

Kitchen - South West walls & garage1.JPG (70.16 KiB) Viewed 7092 times

The roof is actually the superposition of a roof of tiles enhancing the zinc platform initially present (see photos).

From the inside to the outside, from the bottom up, the following is in place:

- 4 cm of Frigolite (PSE) hermetically wedged between the rafters of the wooden frame supporting the platform

Ceiling suspended frame Kitchen1.JPG (325.73 Kio) Viewed 7092 times

- the floor of the platform itself (boards +/- joined), about 2 cm thick
- the old zinc sheet (asphalted on its underside) constituting the original tray of the platform
- the new zinc sheet constituting the tray (in 2 parts) added over the original platform

Roof Slope Kitchen-Sdb.JPG (451.65 Kio) Viewed 7092 times

- the sub-slope of the tile roof (1 m at the highest point, see picture)
- a thin green and blue plastic tarpaulin of the firewood protection type used as a rain cover stapled and wedged between the rafters and the lattis supporting the tiles
- tiles

Problems

1. a completely watertight metal wall (double thickness of zinc) interposed between the roof of outer tiles and the inner false ceiling (PVC paneling not yet placed)

2. an almost not insulated sub-slope (Eternit slate side walls) which is cold and cold in winter

3. Risk of condensation in winter in the ceiling in the vicinity of this wall of zinc? Heat trap in summer

Questions

1. Useful to isolate the sub-slope below the thin blue / green plastic cover to limit the temperature gradient?
The walls are thin (1 concrete block 22cm west and south), the doorway not waterproof and only the window exposed to rain (west side) is double glazed (single glazed south side) .
In summer it is the furnace, especially as the tray of the zinc platform protrudes laterally on each side of the roof and communicates some of the heat of the metal to the rest of the zinc under the roof of tiles.
I think I place a bio-sourced insulation with a good thermal phase shift but it is perhaps also through the walls that the heat accumulates and penetrates in summer (and escapes in winter ...)? To isolate also from the inside?
The local is quite small and I do not currently consider isolation from the outside for lack of financial means.

2. Useful to double the thickness of Frigolite between the rafters of the floor or to place a layer of another insulation (thickness?)

3. To act as a vapor barrier, I have the project to interpose a fine multilayer alumina insulation (acquired, see photo)

Reflective Insulation Multilayer.jpg (54.28 KIO) Viewed 7092 times

on the upper face of the lattice grid (see photo)

Ceiling suspended frame Kitchen2.JPG (194.12 Kio) Viewed 7092 times

which will serve as fixing (MS polymer glue) for the PVC paneling constituting the false ceiling. There will remain a layer of still air a few cm above and below this insulation.

Review

2. Garage (south side below the kitchen / bathroom) and lateral passage in the lateral extension on the east side

Lateral Passage is2.JPG (87.62 KIO) Viewed 7092 times

Sub-slope garage1.jpg (226.13 Kio) Viewed 7092 times

Uninhabited space / heated but I want to isolate to make buffer volume at the back of the house.
I have for this purpose rolls of wool glass (remnants + rolls Knauf Multifit 035 1,20m x 4,10m X 18 cm) to be inserted between the rafters under the blue / green plastic sheet making +/- office rain-wind-screen or 35 PU panels (1,20m x 4,10m x 7 cm). A false ceiling made of laminated parquet 6 mm will complete the insulation to be nailed on the rafters.

I do not intend to place a brake or vapor barrier at the level of this roof (green / blue tarpaulin "rain screen" present on a part) and I hesitate to use the PU which I will perhaps reserve rather for the roof in the attic.

Review

3. Attic attic serving as a heated office

Sous-pente Sud Attic attic.jpg (184.6 Kio) Viewed 7092 times

North Slope Attic Attic.jpg (159.32 KIO) Viewed 7092 times

Under the tiled roof (30!), No windscreen or steam brake, only glass wool in rolls stapled between the rafters. There is no free depth between them to accommodate an additional layer of insulation. Two windows in this room: a Velux double glazed south side and a single glazed east side.
The west side gable is protected to its full height on the outside by Eternit slates

The inhabited / heated volume is isolated from the two sub-slopes (accessible curved to the north, crawling south) by vertical clapboard / plywood partitions on the 4 sides and oblique in height parallel to the roof slopes.

Same problem in summer as the kitchen / bathroom, it is stuffy!

Questions - What to do?

1. Leave the glass wool (correct condition globally) or replace it with 7 cm PU (not enough PU for 14 cm)?

2. Extend the inter-rafters deep or cover their underside with 2 rigid board seating between which to sandwich 14 to 20 cm of wood wool panels?

3. The technique of insufflation of flakes of bio-sourced insulation, although convenient, is not within reach if I intend to do everything myself without a dedicated machine rental. Yes ?

4. Is it necessary to provide a vapor barrier on the interior side of this insulation, leaving a free space or not?
Is the aluminized multilayer insulation also advisable at this level or too impervious to water vapor?


Thank you already for sharing your experience and your wise advice

[DC]

Hello,
Some personal additions with the hope that others will arrive ...

As for the kitchen / sdb (point 1), I was offered elsewhere:

to insulate from above, i.e. not directly under the roof but on the zinc platform (which rests on a floor and itself on rafters accessible from the inside) with the advantage over insulation by the false ceiling as I started to do (frigolite) to avoid, I imagine the condensation in the frame and the wooden floor under the double zinc pan of the platform. Indeed, to reduce the temperature difference between the zinc and the ambient air in the upper part of the kitchen and the bathroom (a lot of water vapor), it is undoubtedly necessary to "keep the zinc warm" and for that the cover directly with insulation.

Insulating between the rafters of the roof over the platform is of no interest as long as the sub-slope of the roof is not itself well insulated (this is the case laterally, simple slates Eternit overlapping vertically on a wood frame, in other words the air circulates almost freely between them in both directions). Exact according to you?

Someone has an opinion?

Attic attic (heated office, 3 point):
Is not this the place where the used (7 cm) PU sheets should be used first, by cutting them to size and sealing them tightly between the rafters? Is it a good insulator (used to store vaccines and will be diverted from its original use? ...) but I can not decide to put it in combination with what
- under the glass wool already in place for more than 30 years and plated directly under the tiles?
- By removing the latter and adding under the PU blanks between the rafters, wood wool panels to ensure a profitable phase shift heat transfer in summer? 7 cm of PU + how many cm of wood wool?

How to proceed ?
The depth of the inter-rafters is barely 6 cm and on the south side at the bottom, there is just room to crawl between the roof and the "enclosure" panels of the office (upholstered chipboard that you will need anyway). boning way, of course), more the space is compartmentalized by the 2 intermediate purlins (the ridge beam is moreover hidden by the false ceiling).

Someone has an opinion?

[Capt_Maloche]

Hello,

I just read diagonally, and I quickly answer on a generality
All that is under tile or zinc roofing must be insulated with the equivalent of 20cm of glass wool, also because of the high surface temperatures in summer.
It can also be a multilayer insulation with reflective surface (red infra) placed under the roof + additional insulation if space is lacking

For the "way", you have to adapt the technique to each case
The vapor barrier must be placed on the inside, this settles all condensation problems

PS; the ideal is to treat each subject independently, the email is a bit long.

[izentrop]

No thin insulation has CSTB certification and even with 2 non ventilated air blades, it is far from 20 cm of glass wool, not to mention the lack of water vapor permeability under the roof https://www.vd.ch/fileadmin/user_upload ... 0_note.pdf

[Remundo]

“mille-feuille” roofs are difficult to isolate.

to isolate well, you have to
1) have a thick and non-convective air gap: eg 20 cm of glass wool (or more) well placed between wood and agglo plates (eg)
2) have a thin insulator with aluminum foils to block infrared in the 2 sense.

you can do this inside the roof and let the junk above breathe.

[DC]

Hello,
All that is under tile or zinc roofing must be insulated with the equivalent of 20cm of glass wool, also because of the high surface temperatures in summer. It can also be a multilayer insulation with reflective surface (infrared red) placed under the roof + additional insulation if space is lacking The vapor barrier must be placed on the inside, this settles all the problems of condensation

Hello and thank you for your brief intervention,
To treat each subject independently, let's start first with:
1. Kitchen / bathroom
1.1 Place the insulation under the roof
This goes in the opposite direction of my last addition, following the observation that was made to me
It does not make sense to insulate under the roof (tiles + pseudo rain cover) if the roof loft is not also insulated laterally (Eternit slates overlapping vertically fixed on a rudimentary wood frame without no insulation).

1.2 Steam shield placed on the inside Cd
In the false ceiling while the double tray of zinc platform (covered with a roof then because it leaked) blocks any issue with water vapor a few cm higher?
In the sub-slope of the roof above the platform while the humidity level is equalized freely with that of the outside air due to the absence of insulation laterally?

1.3 Equivalent of 20cm of glass wool
The glass wool placed under the tiled cover will not prevent the heat from being communicated gradually to all the double zinc tank since it overflows laterally on both sides of the roof (see photo) and creates a buffer volume overheated in summer and the opposite, cold in winter.
Hence the suggestion that I was made to isolate the double tray of zinc DIRECTLY from above (only accessible side from the roof sub-slope) in a 1er time. In this case, the insulation applied to the zinc must be rotproof because the humidity of the atmospheric air may accumulate there, if only morning or evening dew. No ?

1.4 What to place as an insulating equivalent?
- in the false ceiling in addition to the frigolite (only the reflective multilayer insulation, les joined wells wedged between the lattis and contre lattis ie by leaving a volume of air trapped above by the frigolite, below by the PVC paneling the false ceiling (to do again)?
- in the sub-slope on the zinc?
- in the sub-slope laterally and vertically between the wood frame against the slates of Eternit?
- in the sub-slope between the rafters, under the rain cover and the tiled cover?

It is indeed a blanket mille-feuilles, it is difficult for me materially and humanly to go back
In view of the conformation of the places and the time spent to start insulating from the inside (see photo of the wood frame of the false ceiling and frigolite plates stuck between the rafters) and especially to make and place the on zinc tank and then the roof roofed above the platform (which was partially opened initially otherwise )

[DC]

you can do this inside the roof and let the junk above breathe.

Hello,
thank you for your brief intervention

The interior of the roof below the roof tile in the sub-slope so over the double tray of zinc platform?
Or in the false ceiling so from the inside of the rooms?

What in the latter case of the risk of condensation in the floor of the platform directly under the zinc at the approach of cold zinc in winter (see response to Capt-Maloche)?
I already had to replace boards (and rafters) before closing everything and trying to seal ...

[Remundo]

yes by the interior in the room,

compared to the condensations above, you have to let it breathe, the more you try to "seal", the more humid and unhealthy it will be, because you will not be waterproof enough to block all the water, but enough to keep the humidity which will be introduced there.

[DC]

... from inside the room, ... let it breathe ...

Hello,

If I understand you well, compared to what is already in place, you suggest me for the kitchen / sdb, to interpose between the wooden frame (and the Frigolite which is stuck there) and the PVC paneling of the false ceiling (not yet placed):
- 20 cm glass wool (or equivalent)
- multilayer reflective insulation
This respectively from top to bottom ?

Under the roof sub-slope above the platform's double zinc tray, everything will continue to breathe freely and create a call for water vapor from the kitchen / bathroom (presumably saturated with water) air. the exterior through the Frigolite, the wooden floor of the platform and its double zinc wall because this triple thickness is NOT rigorously waterproof to water vapor.
Is that your reasoning / hypothesis?

The air trapped in the 20 cm of glass wool will be an effective insulator inside the room because the little water vapor that will cross the reflective multilayer insulation well joined (vapor barrier) placed below will not stagnate not in the glass wool but will gain the air of the sub-slope through the Frigolite, the wooden floor of the platform and its double zinc tray.
Is that your reasoning / hypothesis?

If so, is it not appropriate to place something other than mineral wool which "regulates" the local humidity very poorly and to consider a bio-sourced insulation also having the advantage of a better thermal phase shift?

Thanks again for enlightening me

[Remundo]

as for the glass wool or other (rock, vegetable fiber ...), I am almost mixed; I found that by putting thin insulation more or less folded back on itself, we had a very thick air and not convective, rather better than stuffing with rockwool. This thin insulation itself containing a little foam / wadding, and many layers of reflective aluminum, the insulation becomes rather formidable, both for thermal conduction than for infrared.

This thin insulation, more metallo-mineral and generally woven in part, has the additional advantage of being less sensitive to water or to "powdering" that wool-foams of any type have known over the years.

There is also the solution of polystyrene plates, easy to cut and paste, which resist well to time.

so I repeat, in outline, you must isolate from the inside, with a false wooden ceiling (non-convective air + aluminum film) and that you let breathe everything that can be at the air and weather outside.