Cold roof or hot roof?

Construction of natural or ecological habitat: plans, design, advice, expertise, materials, geobiology ... House, construction, heating, insulation: you have just received one or more quotes. Can't choose? State your problem here and we will advise you on the right choice! Help in reading DPE or environmental energy diagnostics. Help with the purchase or sale of real estate.
izentrop
Econologue expert
Econologue expert
posts: 13644
Registration: 17/03/14, 23:42
Location: picardie
x 1502
Contact :

Cold roof or hot roof?




by izentrop » 26/04/18, 19:13

Hello,
To change the assignment a dependency that lacked height, without wanting to encroach on the neighbor, we decided to make a flat roof with EPDM seal.

Professional sites and videos on the subject all advise the hot roof. The concern is that the high temperature insulation is very expensive and requires more height than I expected.
Finally, cold roofing requires an air gap that is not so complicated to achieve. http://www.cndb.org/pdf/CNDB/TELECHARGE ... rrasse.pdf
I thought of doing as shown here (cold roof).

On the other hand, why put the vapor barrier on top of the last strain of insulation? I would have rather put it last, as on the walls :?:
Attachments
toitureFroide.gif
RoofingFree.gif (144.7 Kio) Viewed 27006 times
0 x
Christophe
Moderator
Moderator
posts: 79117
Registration: 10/02/03, 14:06
Location: Greenhouse planet
x 10972

Re: Cold roof or hot roof?




by Christophe » 26/04/18, 20:01

Yes it's strange this first small thickness of insulation, then the vapor barrier and then the main insulation ... There must be a reason ... but what ???

I've never been to flat roofs ... they are perpetually annoying sources ... even if it's done well: the EPDM will never hold as long as a conventional roof (slate, tile .. .)
0 x
izentrop
Econologue expert
Econologue expert
posts: 13644
Registration: 17/03/14, 23:42
Location: picardie
x 1502
Contact :

Re: Cold roof or hot roof?




by izentrop » 26/04/18, 22:06

The reason I had it elsewhere
The idea is to create between the ceiling and the vapor barrier, a vacuum in which will circulate all the pipes, electric in particular, which in places cross the ceiling. If the vapor barrier were on the ceiling, it would be damaged.

When the 2th insulation placed on the ceiling, it is actually not mandatory in the strict sense. But the fact of having two successive insulators, crossed supports, improves the overall delivery of insulation because each of the two insulators covers the thermal bridges of the other.

The 1 / 3 is the maximum thermal resistance that can be given to the insulation under PV, to avoid condensation.
If we put zero, we are good, provided that the other insulation is sufficient.
Christophe wrote:the EPDM will never hold as long as a conventional roof (slate, tile ...)
It's recent as a process and there are some interesting estimates http://www.epdm.fr/wa_files/duee_de_vie ... e_epdm.pdf and for my case, it will be the next generation who will maintain : Wink:
0 x
izentrop
Econologue expert
Econologue expert
posts: 13644
Registration: 17/03/14, 23:42
Location: picardie
x 1502
Contact :

Re: Cold roof or hot roof?




by izentrop » 28/04/18, 00:22

New process for high performance insulation to prevent condensation in the frame, summer and winter and I will probably adopt hygro +

0 x
izentrop
Econologue expert
Econologue expert
posts: 13644
Registration: 17/03/14, 23:42
Location: picardie
x 1502
Contact :

Re: Cold roof or hot roof?




by izentrop » 20/06/18, 23:43

Hello,
Finally, I chose the solution of my DIY store that seems to correspond to these recommendations: http://www.programmepacte.fr/sites/defa ... 4-07_0.pdf
It consists of an OSB3 floor covered with a bituminous underlay reinforced with a glass veil. it's glued with cold bitumen glue. Since it's not really glue, you need to point at the top and fix the sides. This underlayer also acts as a vapor barrier.
On top of that, I fixed a PIR insulation (designed for high temperatures). Then the EPDM membrane glued with specific glue beads. I have not managed to avoid creases, but hey, it should not be too tense either.
IMG_20180615_130856.jpg
insulating installation

IMG_20180616_112612.jpg
EPDM being bonded

IMG_20180616_195911.jpg
Almost finished
IMG_20180616_195911.jpg (467.79 KB) Viewed times 26682

IMG_20180616_112733.jpg
rainwater outlet
IMG_20180616_112733.jpg (487.58 KB) Viewed times 26682
0 x

 


Go back to "Real estate and eco-construction: diagnostics, HQE, HPE, bioclimatism, natural habitat and climatic architecture"

Who is online ?

Users browsing this forum : No registered users and 100 guests