Passive house

[Chrysos]

Hello, I'm new, but I'm mainly studying Thermal and Energy Engineering (DUT) in Longwy.

Passive houses being my personal objective for later, I think I can bring some elements:

First, yes, they are passive. The term "passive house" or "passivhaus" is labeled and determines a house with an energy consumption (heating and lighting) below a limit (50 kw per year if I remember correctly).

They are possible and very real: very developed in Germany in particular. They are adaptable to almost all climates. For skeptics who think that these houses are not suitable for the cold, or hot, try to find information on the RMI (Rocky Moutain Institute in the USA): located in the Rockies (large temperature difference) the building is completely passive (one of the first of our era I believe). From what I have seen, they are not furnaces in the summer if they are well designed.

These houses actually depend on well thought-out insulation, with the placement of warmer rooms (bathroom for example) towards the interior of the house, very thick walls to the north (often close to 60 cm thick). They also use classic materials such as cellular concrete or wood, but use ingenuity: paper wall (with frame of course), filled with bales of straw (very insulating, beware of humidity).

They also play on the orientation of the house: bay window facing south, with deciduous trees planted in front: in summer, they provide shade, in winter does not hide the sun. The windows are double or triple glazed, and are often placed at room height (natural light is optimized, less lighting).
It is necessary to take into account the sunshine and the shade (due to neighboring buildings for example). And the fact that the sun is hidden for 1 or even several days is not a problem: the inertia of the building can help overcome this problem.
Thermal bridges (heat transfer phenomena on wall corners, junctions, etc.) are limited to the max, and the roof space is reduced. Roof insulation is essential.
Natural convection is also favored (double flow CMV is still a good solution): no CMV but a light artificial "wind" created by the difference in height of the vents and the difference in temperature in the room. Canadian bridges can help.
We also take into account human activity inside: offices are not designed as a house would be.

Who can do this kind of construction? Most of the time, a competent thermal engineering office and an architect, working in collaboration.

Finally, if all this is not enough (which is rare), we can supplement with geothermal heat pump, some solar panels: in short, relatively low energies but suitable for well insulated houses.


They present two big problems: the obligations of the cadastre can sometimes prevent forms, particular orientations, therefore it is a constraint not to be forgotten.
The second, and not the least, is the cost: counting about 30% of additional cost compared to a traditional house.

The thermal regulations in the building being more and more severe, it is not improbable that one day, one builds the "all passive". But we'll all probably be dead already.


Ps: I am currently working on a hydraulic ram pump project, if someone has advice, do not hesitate to send me a message.

[minguinhirigue]

Hello Chrysos, welcome to the forum.

For the ram pump, do a search on the site, there is a long discussion on the creation of a ram and the difficulties encountered.

Otherwise for the passive house, just a few remarks:
- solar panels and geothermal pumps are used to power ordinary houses. But the € uros invested in insulation are more profitable ecologically and economically (tax credit aside). In addition, given the current origin of European electricity, solar panels must above all replace the closing thermal power plants, and geothermal pumps are to be avoided until the electric park is not green. Having a cop of 2,5 for an electricity produced from fossil fuel with a yield of 0,4, this amounts to burning the gas directly to heat it.
- the buildings of the Rocky Mountain Institute play on a key element that is very difficult to master: inter-seasonal heat phase shifts! In an active or passive system, it is a question of using the capacity of the dry soil to store heat, and to let it migrate gradually (0,8 to 1 m per month of displacement of the heat front). We can thus store the heat of summer, and reuse it in winter, we then "store" the "freshness", useful in summer ... This device is a heavy inertia managed at best, but it is very restrictive: semi-buried house or important earthworks during construction.

[greg33]

The most delicate in passive house is undoubtedly the management of the inertia / insulation of the floor slab.
A blog that shows that http://www.lamaisondurable.com/5-construire-en-paille/ can easily and inexpensively be passive.

[vince8685]

Hello everybody
I myself had an ecological renovation of my house a year ago and since then I have realized all the advantages that this brings:
- energy savings (I spend 3 times less on heating and electricity than before)
-I help protect the environment
- superior comfort to that of a conventional dwelling: the heat distributed uniformly in the habitat, the problems of humidity and odors limited thanks to the ventilation with double flow, the insulation of the external noises and the currents d air and significantly better air quality are some of the most popular elements in a passive house.

If you want to know everything about the passive house, I recommend this article which explains all its characteristics in detail (definition, advantages, costs ....): STOP SPAM

Good continuation

[vince8685]

Excuse me I just saw, that the link was not passed, so if you want more information on the energy renovation you type on google "senova" and it is the 2nd link (the 1st is their website)

[Christophe]

No spam please

[dedeleco]

By looking, quickly, this SPAM site it has all the characteristics of many sites which have the of which to irritate me and typical of the commercial ones:
nothing practical clear fixing the ideas on the techniques used (useless heat pump with great cold pro nuclear, Canadian well / provencal unknown) and the orders of magnitude of the prices.
Result: inspires little confidence because of the genre: we are beautiful, have confidence, we do everything and full of generalities. !!!
Nothing about the basic problem of houses from the 50s to the 90s:
how to reduce the price of heating without spending a fortune on insulation of exterior walls and roof by redoing any roof, walls, windows, or even the house, and without multiplying nuclear power plants, and heat pumps !!
Nothing, Nothing and Nothing !!
Not at all confident in these business methods !!
Pay a diagnosis and you will know what you already know !!!

[HSanders]

I took the trouble to look at this SPAM site and I don't see what you have to say against it. It is a thermal BE that seeks to market its skills. It is not intended to reveal to you online all their know-how in which case you would no longer need them. There are the forum for that and "ecological house" (paper version).

NB: I do not work for the BE, nor for the newspaper!