Passive house project: discussions and details

[bham]

Vincent hat for your project which must have asked you a lot of thoughts.
I have questions about the glazing:
1 ° -What is the orientation of your interseason solar greenhouse?
2 ° - How is your parasol screen made up? is it removable for the winter season?
3 ° - What glazing did you choose?
- Double glazing with a higher light transmission coefficient and g gain coefficient in solar energy compared to a triple glazing but with a worse Ug coefficient of heat loss?
- Or triple glazing, more thermally insulating but less bright and allowing less solar heat input?

[vincent27]

We look forward to seeing you!

1 - The greenhouse is practically full south (slightly SE due to the layout of the land).
2 - The screen is a wooden frame with the slats inclined at 18 °, to let all the winter sun through and protect from the summer sun.
In addition, for protection and aesthetics, we will run plants that lose their leaves in winter.
3 - The glazing will be double glazing because:
The heat and light transmission is better,
The glazing surface not protected by solid wooden shutters (summer and winter insulation) is small.
The gain through triple glazing is negligible. The ratio between the coefficient of a glazing and that of a wall is so enormous that the gain on the small glazed area is ridiculous in an overall assessment. The cost is by no means common and the weight of the triple glazing is monstrous for opening frames.

[bham]

The gain through triple glazing is negligible. The ratio between the coefficient of a glazing and that of a wall is so enormous that the gain on the small glazed area is ridiculous in an overall assessment. The cost is by no means common and the weight of the triple glazing is monstrous for opening frames.

Regarding triple glazing, I have a quote which offers me triple glazing Ug = 0,9 at the price of double glazing Ug = 1,1 and to have triple glazing Ug = 0,6 (coefficient Uw of window Uw = 0,8), I have an additional cost of 19 € / m2, which is not huge. On the other hand, I think that it is preferable to reserve this type of glazing for exhibitions of West / North / East, seen that they have a good thermal insulation but that in return they seem to let pass less heat and light outside.
After if you want to use them on South / South-West / South-East orientations, you should know that they will constitute a good barrier to summer heat but in return a good barrier to winter sun also which can represent a non calorific contribution negligible in this season.

[vincent27]

No window to the west, very little to the north (a little view of the meadow all the same).
The difference in coefficient: about 0,9 to 1 (/ m2).
Coefficient of a wall: 0,1 w / m2 / K
Given the areas in play (5% glazing) ....

In the East, it is the morning sun: very important because it heats up when it is cold.

[bham]

Coefficient of a wall: 0,1 w / m2 / K

Are you sure? I read for a well insulated wall (according to RT2000) a U = 0,45

[vincent27]

The north and west walls will be composed, from the outside to the inside, of wooden cladding on a wooden frame, insulation in straw bales, an interior coating. In all 67cm.
The coefficient is at most 0,2.

[gui42]

carchi, I'm interested in some information. Is there a website where you can find some info?

To answer Timar007, you have to be careful with radon when you install a Canadian well. I am not sure, on the other hand, that this has an importance compared to geothermal energy (ground / air heat pump). You can read this: http://fr.ekopedia.org/Puits_canadien

Vincent, I take my hat off to you too. I guess there is a lot of thinking that has been done. I really liked your explanation on the "house under a roof" to protect yourself from the heat. 2-3 questions me too:
- what space between the roof and the house?
- are you going to build yourself or could you find someone who builds with straw?
- what software did you use for your views?
- if it is not indiscreet, you work in Evreux?

[vincent27]

In a mess :

The views are those of the architect, I don't have much merit on this.
We plan to have the house made, we are consulting with the companies, we respect all the building rules and hope to be able to find a company to do that.
In a few weeks, we will be fixed.
Between the building and the house, there is the space of a small attic, which will be closed openwork, and which corresponds approximately to the slope of the roof + the frame.
Economically, the solution is not uninteresting either, because the hangar is a standard agricultural hangar, of "industrialized" construction.
Thank you for your encouragement, and it is true that the design, in relation to the architect, was an exciting phase.
Now a more boring phase of consultation and work, finally, a still very interesting phase will consist in learning to use the house.

PS: I work on Le Havre.