Member
· Västra Götaland
· 1 710 posts
We are building the timber house in two stories, passive house standard on everything. The house frame is erected and weatherproof, roughly speaking.
We want to complete only the ground floor to move in as quickly as possible, then continue quite directly with the upper floor.
We will insulate with loose fill (ekofiber).
I'm considering the possibility of avoiding dealing with walls, plastic, ceiling gypsum, etc., on the upper floor now.
Instead, I would spray the walls only on the ground floor and fill the intermediate floor with insulation now.
In the next stage, the ceiling and walls on the upper floor will be insulated when I finish it later.
What consequences would this have regarding heat, moisture, etc.?
We want to complete only the ground floor to move in as quickly as possible, then continue quite directly with the upper floor.
We will insulate with loose fill (ekofiber).
I'm considering the possibility of avoiding dealing with walls, plastic, ceiling gypsum, etc., on the upper floor now.
Instead, I would spray the walls only on the ground floor and fill the intermediate floor with insulation now.
In the next stage, the ceiling and walls on the upper floor will be insulated when I finish it later.
What consequences would this have regarding heat, moisture, etc.?
Member
· Västra Götaland
· 1 710 posts
The municipality has promised to give a "final decision" only for the ground floor so that we can move in, the upper floor (as well as the garage) they will handle later when they are ready.Flöjten5 said:
So the question now is, what would happen in construction terms if one had an uninsulated upper floor, for half a year or a year?
Plastic in the middle floor on the warm side of the insulation works fine.
If you are against having plastic there once the house is finished, you will have to settle with wind-proofing fabric or a vapor retarder or something.
If you are against having plastic there once the house is finished, you will have to settle with wind-proofing fabric or a vapor retarder or something.
Member
· Västra Götaland
· 1 710 posts
It sounds reasonable and simple. However, I cannot foresee the consequences of having plastic between the floors when everything is finished. What are the pros and cons of that?Mikael_L said:
I don't think there are any drawbacks with that.
That's actually how it works in most houses built with an unfinished upper floor, once the upper floor is finished. No one wants to tear down all the ceiling just to remove the plastic.
I personally used painter's cover paper there, but we only have a cool upper floor, not cold with outdoor climate, so a little moisture migration through the joists probably doesn't matter here.
That's actually how it works in most houses built with an unfinished upper floor, once the upper floor is finished. No one wants to tear down all the ceiling just to remove the plastic.
I personally used painter's cover paper there, but we only have a cool upper floor, not cold with outdoor climate, so a little moisture migration through the joists probably doesn't matter here.
But wait a minute!
If you have eco-fiber (cellulose, flax, or something similar), isn't it because you don't want plastic in the walls and ceiling?
Or is there something I haven't understood?
Of course, I don't know what "passive house standard" is.
Is it a set standard, or does it just mean well-insulated?
However, it is probably important that you have functioning ventilation in the living areas, so moisture is managed and transported away properly.
If you have eco-fiber (cellulose, flax, or something similar), isn't it because you don't want plastic in the walls and ceiling?
Or is there something I haven't understood?
Of course, I don't know what "passive house standard" is.
Is it a set standard, or does it just mean well-insulated?
However, it is probably important that you have functioning ventilation in the living areas, so moisture is managed and transported away properly.
Is it possible to achieve passive house standard with loose-fill insulation?
"The Swedish standards for passivhus are that the supplied power must not exceed 10 W per square meter for multi-family houses and 12 W per square meter for detached houses, in the design outdoor climate. In the northern climate zone, this is increased by 4 W per square meter."KnockOnWood said:
wikipedia
Thank you, I have now read the wiki article.miksil said:
And I don't think this is a Swedish "standard" or "norm", it's really a fabrication, used for some purpose, probably for marketing. Of what? Maybe expensive consulting services. Quite recently there was a guy here who was a certified passive house expert. It's probably something you can make money from.
"The Swedish standards for passive houses are that the supplied power must not exceed 10 W per square meter for multi-family houses and 12 W per square meter for detached houses, under design outdoor climate."
10 Watts? 12 Watts? Should it be the average power need over the year?
12 x 24 x 365 / 1000 = 105 kWh/m2 is well above the building requirement of 55 kWh/m2 per year.
And where does "household electricity" and hot water electricity go? Should they be included or not?
Either I'm calculating wrong or there's something I don't understand.
My house, which is absolutely not a "passive house", consumes on average less than 6 Watts/m2. Including everything.
Member
· Västra Götaland
· 1 710 posts
"Passive house standard" for us means well-insulated and airtight, with FTX ventilation. So much insulation and low u-values that the house stays warm with the help of household electricity and body heat. However, we might not 100% follow the norms set by "someone" in Sweden for the house to be called a passive house by these puritans. Oh well. Therefore, maybe that discussion can be left in favor of the main question.
A passive house is built (at least by us...) super tight with a vapor barrier on the warm side of the insulation. We thus need plastic on the inside of the walls that goes seamlessly into the ceiling when it is finished. This is how most houses are built today, even though the precision clearly varies. Ventilation is handled by an FTX system where incoming air is heated via a heat exchanger by the outgoing air.
Mikael_l managed, as usual, to pinpoint the important thing:
I don't think there are any disadvantages to it.
In fact, this is how it is in most houses built with an unfinished upper floor when that floor is later finished. Nobody wants to tear down all the inner ceiling in the house just to remove the plastic.
Well said, there are many house manufacturers that leave the house with an unfinished upper floor to the end customer. But my guess is that they still plastic and insulate all the way up, and don't do it the way I was thinking.
The question is also whether you can succeed in plasticizing the floor structure so well that no moisture seeps up. For example, around the staircase opening, it can be difficult.
Probably need to consider at least one more round before making a decision.
A passive house is built (at least by us...) super tight with a vapor barrier on the warm side of the insulation. We thus need plastic on the inside of the walls that goes seamlessly into the ceiling when it is finished. This is how most houses are built today, even though the precision clearly varies. Ventilation is handled by an FTX system where incoming air is heated via a heat exchanger by the outgoing air.
Mikael_l managed, as usual, to pinpoint the important thing:
I don't think there are any disadvantages to it.
In fact, this is how it is in most houses built with an unfinished upper floor when that floor is later finished. Nobody wants to tear down all the inner ceiling in the house just to remove the plastic.
Well said, there are many house manufacturers that leave the house with an unfinished upper floor to the end customer. But my guess is that they still plastic and insulate all the way up, and don't do it the way I was thinking.
The question is also whether you can succeed in plasticizing the floor structure so well that no moisture seeps up. For example, around the staircase opening, it can be difficult.
Probably need to consider at least one more round before making a decision.
I think it means that at the coldest outdoor temperature, you must not supply more than these 10 or 12w per sqm. If this then means you have to limit the stove when you start the stove to cook, I don't know (probably not). But it's not average consumption, it's peak consumption.KnockOnWood said:
Even if you wrap it in plastic, it is very important that you seal the stairwell and any other passages between floors, otherwise you will get mold damage on the upper floor.
The upper floor of my house is largely uninsulated and unfurnished. There's one room with insulated walls and ceiling. It's probably looked that way since the house was built in 1948 (I moved in last summer). Last winter, when it was the coldest outside, it was a few degrees below freezing up there.
There is no plastic between the floors. Just about 15-20cm of wood shavings insulation. By the stairs, there's just an ordinary interior door on the ground floor that keeps the cold up there.
There are no signs of mold, except in one small spot where there was a leak in the roof. (there was no damage to the floor beneath the leak)
The upper floor of my house is very airy and not at all sealed, so maybe that's why it has survived all these years.
It will be fun to furnish it someday in the future, but first, I need to sort out everything else.
(I moved in last summer). Last winter, when it was the coldest outside, it was a few degrees below freezing up there.There is no plastic between the floors. Just about 15-20cm of wood shavings insulation. By the stairs, there's just an ordinary interior door on the ground floor that keeps the cold up there.
There are no signs of mold, except in one small spot where there was a leak in the roof. (there was no damage to the floor beneath the leak)
The upper floor of my house is very airy and not at all sealed, so maybe that's why it has survived all these years.
It will be fun to furnish it someday in the future, but first, I need to sort out everything else.