forums energies: society, ecology and clean technologies

published: **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 :?:

published: **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 .. .)

published: **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:

published: **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 +

published: **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.

: insulating installation

: EPDM being bonded

: Almost finished; IMG_20180616_195911.jpg (467.79 KB) Viewed times 27581

: rainwater outlet; IMG_20180616_112733.jpg (487.58 KB) Viewed times 27581

forums energies: society, ecology and clean technologies

Cold roof or hot roof?

Cold roof or hot roof?

Re: Cold roof or hot roof?

Re: Cold roof or hot roof?

Re: Cold roof or hot roof?

Re: Cold roof or hot roof?