Hello,
I am starting an attic project. Roof insulation is the first step
Here is the existing one:
I currently have a farmhouse type structure. The carpenter comes in the next few days to lay the battens under the arbas of the farmhouse and then break it. Thus, we transform the framework without discovering ...
On the ground, I simply have joists under which are fixed the furs of the ceiling of the last floor.
Between the joists, I have the current insulation: Blown mineral wool.
I see the tiles directly when I go upstairs. There is no rain screen ...
The housing is new, it was completed there 2ans 1 / 2
The situation
I live in the south of the Var, a few km from Toulon. The house is oriented East / West with a roof with two slopes
What I plan to do
I will close the floor of the new floor on the joists. The current insulation will be sandwiched between the ceiling of the current top floor and the floor of the future floor.
This new floor being above the current insulation, I will isolate under slope.
I plan a first layer of mineral wool ep 100mm (R2,5) between the arbas so directly under the tiles
http://www.pureone.fr/fr/produits-pure-40-rp
On this first layer, I will disembowel the vapor barrier
I then plan a second cross layer of the same product under the arbas, between the battens
This will make me a total thickness of 200mm and a R = 5
Is this sufficient? It seems to me that yes because on the one hand I am not at all in a cold region and then I keep the existing insulation and therefore the existing floors will be "over-insulated"
I can switch to a R = 6,15 for 2,5x more expensive ...
Only question, the lack of rainscreen. I tell myself that it will not be more embarrassing than today. I do not see why it would suddenly become essential
In short, here is my "study" and I would like your opinions on all that
Thanks in advance [/ u]
Isolation Project
- minguinhirigue
- Éconologue good!
- posts: 447
- Registration: 01/05/08, 21:30
- Location: Strasbourg
- x 1
Hello,
First point, the rain shield. It is not essential if the slope of your roof and the tile system (interlocking for example) provide sufficient protection. However, the risk can not be excluded if the slope of the roof is weak or if some tiles are deteriorated (which will come with the time) s.
So I advise you to put a first bed of insulation with a coating to limit the risk of humidification. I know that for wood wool this is done with paraffin-coated ones. For mineral wool, the presence of a layer of Kraft can do the trick. Attention, in this case, it is necessary to place a continuous vapor barrier on the last inner face of the insulation.
Second point, for winter insulation, R = 5 in Toulon is probably enough. However you will have to deal with summer overheating, often ignored. And the phase shift of conventional glass wool is zero for this purpose.
In practice, you need a phase shift from 10 to 15 h to limit overheating (the peak heat of the day comes at night). You can get it with 25 30 cm of high density rock wool in rigid or semi-rigid panels, or with 20 cm of high density wood wool. Take a look at this site, it does not necessarily serve as a reference for your case, but it gives you the keys to choose your insulation: http://www.acqualys.fr/pages/index.php?id=574#epaisseur%20recommandée
Pay attention to summer overheating, the uninhabitable attic in summer is a shame! In your case, I would strongly advise you to choose wood wool 20cm thick, or for lack of the thickest rock wool possible. But it will be a little more expensive than what you have planned.
First point, the rain shield. It is not essential if the slope of your roof and the tile system (interlocking for example) provide sufficient protection. However, the risk can not be excluded if the slope of the roof is weak or if some tiles are deteriorated (which will come with the time) s.
So I advise you to put a first bed of insulation with a coating to limit the risk of humidification. I know that for wood wool this is done with paraffin-coated ones. For mineral wool, the presence of a layer of Kraft can do the trick. Attention, in this case, it is necessary to place a continuous vapor barrier on the last inner face of the insulation.
Second point, for winter insulation, R = 5 in Toulon is probably enough. However you will have to deal with summer overheating, often ignored. And the phase shift of conventional glass wool is zero for this purpose.
In practice, you need a phase shift from 10 to 15 h to limit overheating (the peak heat of the day comes at night). You can get it with 25 30 cm of high density rock wool in rigid or semi-rigid panels, or with 20 cm of high density wood wool. Take a look at this site, it does not necessarily serve as a reference for your case, but it gives you the keys to choose your insulation: http://www.acqualys.fr/pages/index.php?id=574#epaisseur%20recommandée
Pay attention to summer overheating, the uninhabitable attic in summer is a shame! In your case, I would strongly advise you to choose wood wool 20cm thick, or for lack of the thickest rock wool possible. But it will be a little more expensive than what you have planned.
0 x
-
- Similar topics
- Replies
- views
- Last message
-
- 12 Replies
- 10083 views
-
Last message by eclectron
View the latest post
03/11/19, 20:29A subject posted in the forum : Heating, insulation, ventilation, VMC, cooling ...
-
- 0 Replies
- 5435 views
-
Last message by Nebula
View the latest post
21/07/14, 23:33A subject posted in the forum : Heating, insulation, ventilation, VMC, cooling ...
-
- 99 Replies
- 41378 views
-
Last message by mathieu444
View the latest post
08/04/11, 10:08A subject posted in the forum : Heating, insulation, ventilation, VMC, cooling ...
-
- 12 Replies
- 9849 views
-
Last message by dedeleco
View the latest post
08/08/10, 15:14A subject posted in the forum : Heating, insulation, ventilation, VMC, cooling ...
-
- 3 Replies
- 9645 views
-
Last message by manitou22
View the latest post
28/10/09, 23:17A subject posted in the forum : Heating, insulation, ventilation, VMC, cooling ...
Back to "Heating, insulation, ventilation, VMC, cooling ..."
Who is online ?
Users browsing this forum : Google [Bot], Google Adsense [Bot] and 328 guests