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Comment by wheresmyusern | Hacker News Reader

im sorry but this means that the houses were not designed well. if you have a house that is well insulated, and that does not leak heat from the ventilation system, that means that it will stay the same temperature. if you go through a cycle of cooling and then coming home to a hot house and then cooling again, eventually you will stop coming back to a hot house. the only explanation is that there is a leak (poor design) or that heat is being injected into the house through sunlight or some other means. i would put my money on sunlight making its ways through poorly implemented windows.

by the laws of physics, if you have a passive house kind of house, you will not be able to come home to a hot house repeatedly.

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It kind of sounds like GP's was just a regular house, opening windows etc. at night and closing everything during the day is what I do with my regular house. I'd expect a passive house to handle a lot more of this without requiring those types of interventions, and be a lot more successful at it. Like...I don't think something qualifies as a passive house if it doesn't work.

Probably a design with south facing windows simply because while 28 degrees is unacceptable, so is an architecture with no windows in one or more directions.

Also, all power used inside the building must be dissipated somewhere. In a very well insulated building even just 500W idle power inside quickly adds to the air temp.

Like a fridge / freezer which is usually left on 24/7.

first of all, a house with no windows on a single side is not unacceptable. i live in a place that only has windows on one wall and i find it more than acceptable. look at all the houses that people have built with no windows on one or more faces. there are innumerable examples that prove you wrong. and on top of all that, its a completely subjective thing, whether a house needs a certain number of windows. you cant just say that leaving out windows on one side is objectively and definitively unacceptable. thats bullshit.

furthermore, there is no need to omit windows on any side, even the south side. typically, a shading structure is placed that blocks direct sunlight during the warm seasons when the sun occupies those seasonal positions in the sky. these shading structures do allow sunlight when the sun is in its cold season positions, when sunlight is appreciated inside. going even further, windows should filter out any light that is not within the useful spectrum of visibility -- this reduces heat load from the sun. movable shading can also be used to block the sun only during the warm season.

there are countless examples of houses that have lots of windows and do not get too hot.

moving on to power. the back-side of your refrigerator should be vented, not exposed to your inside environment. led bulbs produce very little heat. overall, as i have said elsewhere, you will always need some amount of cooling and heating capacity.

it remains true that a properly implemented passive house will not get too hot, despite your shortsighted observations.

I have almost no windows on the North/East because the idea is to maximize light and have as little heat loss through the windows as possible (heating here is far more expensive I’ve the year than cooling).

In hot and stable climates it’s probably common to not have large windows to the south, but in places where you have +30C in summer and freezing to -20 and dark all winter it’s hard to architect for all seasons. I wouldn’t give up the 4h daylight in my south windows in winter, even though they make the house too hot in summer. Shading that can be removed is probably the answer.

Vented rears for freezers, how does that work? Do they typically sit in an outer wall, or do they have ducts venting so they can be placed anywhere? I have never heard of those.

venting appliances that create heat is not done anywhere as far as i know. the refrigerator is the main appliance that needs this because it is essentially a heat pump that runs all the time. insulating it well and venting its hot side is very simple conceptually and is completely doable.

not venting heat generating appliances inside the house is a design flaw and does not follow passive house principles. because nobody addresses this problem, i do consider almost all passive houses to be incorrectly designed and implemented.

the reason why this problem is not addressed is because some degree of cooling capacity is usually present and can keep the house cool despite this flaw. the heat load from the appliances is relatively small and so it is overlooked -- small compared the loads encountered in old-style houses. also, heat generating appliances are a benefit during the winter, so the problem only exists half of the time.

in an ideal system, all heat generated by all systems in and around the house would be channeled and utilized correctly. we are coming closer to that goal.

True. These things are done in Travel Trailers and RV’s

You may not have to remove shading in winter. The sun is higher up in the air in summer, so an overhang can be all you need (https://greenpassivesolar.com/passive-solar/building-charact...)

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