My economic maist in Ytong, thin insulation for the roof?

[benjifous]

hello everyone, I'm building my house in the southwest. It is a project that I took a while to draw because I wanted to take into account the practical, ecological and aesthetic side ...
I did earthwork so as to bury the north facade of about 80cm. I oriented the main facade due south (10 ° east) and a return to hide from the western sun in the evening.
the construction is a 30cm siporex, the windows are double glazed with argon and irt treatment.
there I am at the frame, I made the tradi, with plates of plywood of 22mm, an insulator in particles of wood of 40mm and an OSB of 9mm on top. thereafter I intend to add a thin insulation type Actis max wool which is supposed to have an R of 6,1, but I still hesitate when the effectiveness of these products.
here for the moment, thereafter I will keep you informed.
See you everyone...
ps if you have an opinion on the insulation, do not hesitate!

[benjifous]

[Christophe]

Nice house in Ytong, good choice of material!

We do not see well on this image, you have the roof slabs in Ytong also?



Otherwise do not count on thin insulation to insulate your roof: I do not know the Max Laine but if it is a thin insulation, there is a good chance that the R of 6 is an abusive advertisement and the 40 mm that you have already put are (very) insufficient for the roof!

Here is a document that should greatly help you in your choice: are thin insulators a correct insulation solution?

In the best case, according to these tests, a thin insulator has an R of 1.7 and still has to be installed with 2 unventilated air knives of 20 mm each, in the end the thickness is more than 40 mm is less effective than a conventional insulation!

So I advise you to put a layer of insulation to obtain, at least, 200 mm equivalent wool insulation. To comply with the RT2005 standard, you would need at least 250 mm equivalent. See https://www.econologie.com/rt2005-les-re ... -3512.html

Otherwise you have the same (small) problem as with us (we are also in cellular concrete), some of your lintels are in conventional reinforced concrete = thermal bridges.

I do not understand why there has not been a lintel in an armed ytong since the time that the ytong has existed ... in our time at the beginning of the 80s I am fine but in 2009 ???

Apparently you have several types of lintels, right?

[minguinhirigue]

I would say the same thing as Christophe for thin insulation, the only use that you can find for them in your case, it is an insulation in rain shield (but I doubt that they are certified for that) or in vapor barrier, in addition 20 to 30 cm thick wool insulation.

There is a post on the forum about Actis wood wool, it is not bad, you also need thin insulation, but reserve these products for very specific cases (little space, limitation of radiant heat under a metal sheet on the roof, materials offered , ...)

Otherwise, it's a beautiful project ... well done.

Christophe, for the Ytong lintels, if they could not overcome it, I think it is because the material is too fragile. The local constraints imposed by concrete reinforcing bars are too great. Some adaptations exist, with the outer part of the lintel in ytong, but it is always three times less good in thermal than a complete block of aerated concrete.

[Christophe]

Christophe, for the Ytong lintels, if they could not overcome it, I think it is because the material is too fragile. The local constraints imposed by concrete reinforcing bars are too great. Some adaptations exist, with the outer part of the lintel in ytong, but it is always three times less good in thermal than a complete block of aerated concrete.

Ok thank you for the explanations. It would not be what he used on the ground floor bay on the right as well as at the door on the right facade where the lintels are white?

With us, we have the roofing slabs in reinforced Ytong (see subject insulation by cellulose wadding) so the armed Ytong exists .... and seems to last.

But it may not be enough for a lintel. Strange anyway because we could very well imagine lintels armed there with double height / blocks so have a lot more inertia ... finally the industrialists know what they are doing!

[benjifous]

thanks for your answers and compliments.
in fact I have all the lintels in ytong, except that it is not the same densities as the other blocks, but they are white too.
it is the roller shutter boxes which are below the lintels which are made of wood particles.
voila, I liked what to see for my insulation, because I am with an effective R of 1,6 is not huge.
otherwise my ceiling is in white laquered wood, to slice with my burnt douglas beams.

[Christophe]

Ok for the lintels!

For the 1.6 of the roof is clearly insufficient unless it is a lost roof and you isolate the floor?

Otherwise you can easily put beautiful panels of wood wool (or rock wool) between the rafters of the frame! Apparently you have more than 10 cm of "empty".

I put some at home which is less expensive than extruded polystyrene: https://www.econologie.com/forums/sylvactis- ... t8944.html (from actis too!)

[benjifous]

CA there is my roof is finished since time, finally it is composed of: a wooden under-laminated underside of 22MM, 40MM of flexible wood wool type insulation, an OSB of 13MM, 100MM of extruded polystyrene, and a 7-layer thin insulation with an air vacuum of 25MM ...
On the other hand I have a terrace roof which I must waterproof and revegetate ...
For the waterproofing I thought to make it out of polyester (like swimming pools) on the other hand I struggle to find the plates to drain.
If someone has tips I'm interested ...
thanks.