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Swedish Couple Builds Greenhouse Around Home

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Re: Swedish Couple Builds Greenhouse Around Home

#151

Post by eecc »

WJW wrote: post #59
eecc wrote: post #46

And in Amsterdam - of all places, the capital of one the countries most threatened by rising sea levels - the idiots keep gas fired terrace warmers burning at full blast. Cycling through the city feels like the deck of the Titanic. :S

We'll build the dikes another few metres taller. Shrug...

You seem to be missing the point.

It’s not just about building higher dikes.

It’s about the ethical soundless of pissing tons of CO2 in the wind just because you can’t be bothered to wear a sweater. (What does that inscription next to Leidseplein say?)

Edit: it’s also not just about higher dikes in NL, the effects of that CO2 goes well beyond the Dutch border. It’s Global Warming after all... global.

The cognitive dissonance of this attitude, compared to the Swedes building greenhouse homes to save on energy, is what makes it feel like we’re swingin’ on the Titanic.

Re: Swedish Couple Builds Greenhouse Around Home

#153

Post by dagss »

war1025 wrote: post #132
gavia1 wrote: post #20

I wonder how they control humidity inside the home and prevent mildew/mould? The air in the greenhouse would be very humid all year round I would have thought?

I am a little confused about this fear people have of mold and mildew in their houses. Up until very recently people's houses weren't far off from the outside environment. Generally in the summer the best they did was keep the rain out and provide some shade. Houses weren't uninhabitable mold pits back then, why would they be now?

Well just as an example, around here concrete cellars were usually not insulated before. They were storage areas.

In the 80s people started insulating them in the wrong way (on the inside), creating a condensation point between the insulation and concrete => mold.

These days we have learned that cellars must be insulated on the outside (by digging up the garden) or somehow make sure humid indoor air dont make contact with concrete behind insulation.

If you basically don't have plastic and insulation then mold is less of a problem, but you also need to spend a ton of energy keeping the house warm...

Re: Swedish Couple Builds Greenhouse Around Home

#155

Post by macleginn »

fyfy18 wrote: post #141
btbuildem wrote: post #65

Earlier quoted context omitted.

I think standard household activity would generate a lot of humidity. Usually dwellings vent outside, but here the outside is in a larger "inside". I'm guessing the greenhouse has its own air regulation set up.

In my part of Northern Europe, in the winter the issue is keeping the inside humid enough. During winter when the air temperature is -10c or less there is basically no water in the air. We have a MHRV system, but it doesn't account for humidity, so will happily replace all the air inside with dry air from outside (I'm trying to automate it with HASS). Our bathroom fan has a humidity sensor, so doesn't run so much in…

Soviet Moscow flats are notorious for constant ~15% humidity in winter. Somehow they manage this even when there is a thaw outside and humidity is quite high.

Re: Swedish Couple Builds Greenhouse Around Home

#156

Post by dagss »

gavia1 wrote: post #20

I wonder how they control humidity inside the home and prevent mildew/mould? The air in the greenhouse would be very humid all year round I would have thought?

I could be wrong but I think mould appears when humidity condenses to water drops. So you need both humidity and a temperature contrast (e.g., hot inside air meets a cold wall).

So as long as the inside and outside of the house has the same temperature, condensation in random spots should not happen?..

Condensation will be on the glass panels, where mould cannot grow.

Re: Swedish Couple Builds Greenhouse Around Home

#157

Post by dagss »

tigershark wrote: post #146
telotortium wrote: post #12

Earlier quoted context omitted.

No reason a ventilation fan can't be installed - that's standard on modern air-conditioned and insulated houses (a "whole-house fan") precisely in order to rotate the air.

Then they will lose all the advantages of the green house if they get cold air from outside...

Balanced ventilation (not sure what the English term is) is standard these days and recovers about 90% of the energy (heats air going in using the air going out). I have one at home.

Dont know if they have one set up, but they could. But possibly the sun already warms it enough even in winter that it is not needed even with natural ventilation.

Re: Swedish Couple Builds Greenhouse Around Home

#158

Post by mirimir »

fyfy18 wrote: post #141
btbuildem wrote: post #65

Earlier quoted context omitted.

I think standard household activity would generate a lot of humidity. Usually dwellings vent outside, but here the outside is in a larger "inside". I'm guessing the greenhouse has its own air regulation set up.

In my part of Northern Europe, in the winter the issue is keeping the inside humid enough. During winter when the air temperature is -10c or less there is basically no water in the air. We have a MHRV system, but it doesn't account for humidity, so will happily replace all the air inside with dry air from outside (I'm trying to automate it with HASS). Our bathroom fan has a humidity sensor, so doesn't run so much in…

Yeah, same here. When it's -10 C or less in the winter, relative humidity can drop to 15%. Because we have a standard heat-exchanger HRV. The rotating-filter ones do manage humidity, but they also tend to freeze up if indoor humidity goes too high.

So we end up using an aerosol humidifier in the winter, and AC plus a dehumidifier in the summer.

Re: Swedish Couple Builds Greenhouse Around Home

#159

Post by jogjayr »

dagss wrote: post #157
tigershark wrote: post #146

Earlier quoted context omitted.

Then they will lose all the advantages of the green house if they get cold air from outside...

Balanced ventilation (not sure what the English term is) is standard these days and recovers about 90% of the energy (heats air going in using the air going out). I have one at home. Dont know if they have one set up, but they could. But possibly the sun already warms it enough even in winter that it is not needed even with natural ventilation.

> Balanced ventilation (not sure what the English term is)

Heat exchanger: https://en.wikipedia.org/wiki/Heat_exchanger#HVAC_air_coils

Re: Swedish Couple Builds Greenhouse Around Home

#160

Post by dagss »

jogjayr wrote: post #159
dagss wrote: post #157

Earlier quoted context omitted.

Balanced ventilation (not sure what the English term is) is standard these days and recovers about 90% of the energy (heats air going in using the air going out). I have one at home. Dont know if they have one set up, but they could. But possibly the sun already warms it enough even in winter that it is not needed even with natural ventilation.

> Balanced ventilation (not sure what the English term is) Heat exchanger: https://en.wikipedia.org/wiki/Heat_exchanger#HVAC_air_coils

That may be. The word we use is more a property of the ventilation system ... that you blow as much air into the house as out of it, active airflow in both directions. (As opposed to older ventilation where only exhaust has a fan.) This facilitates plugging in a heat exchanger.

To be clear I did not mean HVAC, which requires (some) energy in itself.

At home I do not have HVAC. However, the outbound air passes through a rotating metal structure that sucks up the heat from outbound air and releases it into the colder inbound air. Just using the temperature gradient that is there naturally. Passive energy transfer.

Same principle can be used with hot water (e.g. from showers).

Then one can put HVAC on top of this for active warming.

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