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Comment by Etheryte | Hacker News Reader

Not some of the heat, all of the heat save for what your body generates and such was from neighbors. In most reasonably managed apartment buildings what you did is forbidden because it means your neighbors just have to heat more since their walls will leak heat to you. In total it rarely ends up being an energy save because the losses are bigger this way than if everyone kept a uniform temperature.

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I have been a renter for most of my adult life and I own several apartments that I would argue are "reasonably managed" and I am not aware that a landlord (in Germany) can prevent tenants from "leeching" heat from neighboring apartments. A renter usually has to guarantee a reasonable minimum temperature in the apartment, as well as regular fresh air, both to prevent mold. But the level of heating required for this is way below 20°C.

Also: I'm pretty sure that in most reasonable scenarios not heating one apartment in a house that has a decent outer layer of insulation would overall reduce energy input, because the overall average temperature would decline and heat would propagate more efficiently between apartments than to the outside. But I'm no expert so what do I know.

Where I am, the heating costs include a shared portion for this reason... you can turn your heating completely off and still pay 1/3 or 2/3 of a regular bill (don't remember) as the building's "shared" heating costs.

That also means if you turn on your heating, you add to both your bill and some of the shared costs others pay.

I live in a modern, well insulated building as the grandparent comment. I haven't run the heat for years, we need to occasionally open the windows cos it gets too warm and stale obviously, i don't think it makes sense to force me to turn on the heat even more and open the window even more.

edit: this was more a mix of reply to the parent comment and a bit to yours, sorry got it in the wrong spot.

> In total it rarely ends up being an energy save because the losses are bigger this way than if everyone kept a uniform temperature.

Really? GP is effectively acting as an apartment-size layer of insulation between neighbors and the outside. Put another way, if everyone did what GP did (for instance, lower thermostat to 20C) the entire building would be cooler and use less energy. Perhaps GP’s behavior even encouraged others to lower their thermostat because of higher electric bills!

20 C == 68 F.

Is that considered a low temp for heating your house? I think that's about a perfect daytime temp summer or winter. At night that would be too warm honestly.

Keeping my home at 68 degrees in the winter at all times would be > $300/month, and would be an insane minimum to enforce.

Apples and oranges, depending on where you live it can be anywhere between insanely expensive and practically free to keep your house at that temperature.

It’s about 4-5 degrees C too cold for me.

> GP is effectively acting as an apartment-size layer of insulation between neighbors and the outside.

Wat. Do you honestly believe that other apartments are on the inner side of the building and his is on the outer side?

> Put another way, if everyone did what GP did

Everyone would be cold, and the building itself would be cold

This is so demonstrably false it needs calling out. The overall losses will be lower, which is easy to note by considering the heat flow across the outer envelope which scales monotonically with the internal temperature. If one apartment is at a lower temperature for whatever reason, the total loss to the outside will be lower. Yes, one apartment might need to produce more heat to compensate for a neighbour being cooler, but that would be more than compensated for by the savings of that cooler apartment. This is absolutely just insulation.

But the apartment wasn’t colder, he says it stayed at 20C. That energy has to come from somewhere.

Yes, from the neighbours and internal generation. That's not disputed. What I was challenging was the idea that all the apartments being at the same temperature is a net saving (presumably over some of them being cooler as described in the GP).

What you call a reasonably managed apartment, I call an apartment woefully built without reasonable insulation between dwellings. If I leave for the winter, why should I pay to heat a space I won't be in?

Normally apartments are built for living in them, and majority of dwellers don't leave it for more than vacations and holidays.

Having thick isolation between apartments is a waste of resources in most cases - better to put on the whole building.

So people in the UK aren’t allowed to lower their temps when they leave for vacation? Am I really supposed to believe this? I guess you’ll tell me you need a license to watch TV next.

I'm not from UK so can't answer that.

But if you think logically, there are some things you can't do in apartment, e.g. listen to loud music at night, or drill holes when others might be sleeping.

Turning down heating to zero is one of them. AFAIR in some places there is a limit of how low your heating should be and if it is lower then you still pay a given set price - this is to discourage cheaters.

The added cost of the extra insulation likely outweighs the cost of you heating the apartment when you're not there.

It can't be both ways. Either the home is sucking up enough heat from the neighboring units to be significant, and so it warrants insulation, or it's not, in which case why would management care about something so tiny?

Insulation is the first thing you do to improve the thermal characteristics of a home. It's not expensive.

Because a subgroup of people got together and decided their interests are more important than everyone’s individual interests.

>In total it rarely ends up being an energy save because the losses are bigger this way than if everyone kept a uniform temperature.

I really don't see how that can be possible except for some rare cases

> the losses are bigger this way than if everyone kept a uniform temperature.

Pretty sure this is incorrect. Conductive heat flow goes with the temperature difference. The higher the temperature difference, the more heat flow. If you kept your room cold versus everyone else, then your room would be leaking heat to the outside less than everyone else's, assuming everything else equal.

Never heard of such restrictions in the UK.

I used to live in a flat where we never turned the heating on at all. It got so warm we had to open windows even in winter. If my neighbors were responsible, I wish they would have turned their heating down!

can someone explain to me how this would not save energy? I have a very basic model in my head of "energy in/energy out" and it feels like if in the end one person is taking advantage of leakage (but probably not enough to actually get to the same temperature as people around them), then there would be less energy used, but are there non-linear forces at play or something?

I'm confused too: my intuiton/understanding would be that:

* The total energy use would be lowered.

* The energy use of the neighbors would be somewhat higher.

I don't believe the energy consumption would be higher, but a plausible mechanism is this: When your neighbor heats their apartment only, their radiators need to produce more power than if all apartments are heated. To generate more power, the radiators need hotter water. Producing hotter water lowers the efficiency of the heating system. So there is a tradeoff curve between higher heat loss (because more parts of the building are warm) and heating efficiency. There might be a point where it makes sense to heat more of the building, but I doubt that somehow.

> Not some of the heat, all of the heat save for what your body generates and such was from neighbors.

Also cooking, refrigeration, lighting, electronics..

I generally have my heating at 18, anything more I am opening windows or taking off my jumper. 20 degrees would be too hot for me, if I lived in an apartment that mandated 20 degress heating at all time I wouldn't be happy about it.

My apartment mandates 23C in most rooms, 25C in one. Also, once you hit 16C, you get rapidly growing mold everywhere due to increase in humidity compensating lower temperature.

I don't know what you apartment mandates, but the rest of the post is simply not true.

We keep our heat at 16°C during the day, 15°C at night. We don't have any mold issues.

Furthermore, humidity drops with temperature, as cooler air can't hold as much moisture as warm air.

It's a problem if humidity on the place is high and building is insulated crappier.

> humidity drops with temperature, as cooler air can't hold as much moisture as warm air.

This encourages mold

That can lead to water condensing on other surfaces which on the right surface can start mold growth. Wallpaper, exposed wood, stucco walls and some painted surfaces are all subject to this.

> We keep our heat at 16°C during the day, 15°C at night.

Why would you do this to yourself? I meaning living in such woeful conditions.

That is really cold, but the temperature I would keep an unused house at. If I tried to do that in our current place, my family would be extremely angry - we have it at 20 and even then I get complaints.

Your apartment mandates rooms stay at least 73.4 degrees F? 77 in another? I'd be wearing a tanktop indoors at all times. I'm having a very hard time believing this is true.

It's a common clause in rental agreements so that any mold problem can be blamed on the tenant because obviously they didn't heat their rooms to some ludicrous temperature while also opening the windows ten times a day.

Well my landlord was repeatedly explicitly pointing out these in the contract. I guess he doesn't want this luxurious apartment to degrade and lose value.

If it were my apartment, I just wouldn't do it. If the heating were centrally controlled, I'd open up the windows. 77F is simply way, way too hot inside, unless it's the summertime (and even then I'd be wearing shorts). That's insanely hot, and the idea of wasting all that energy to maintain a literal sauna inside your apartment is insane.

You got an apartment that was so badly designed wrt air flow that it needed 23C temp every second of every day?

Whoops

>In most reasonably managed apartment buildings what you did is forbidden because it means your neighbors just have to heat more since their walls will leak heat to you.

In your idea of "reasonably managed" buildings, everyone is forced to keep the heat on way too high, so a bunch of people open their windows wide open to bring in cool air, resulting in a massive and ridiculous waste of energy. The problem is that some moron in charge of the thermostat wants it much hotter (in the winter) or colder (in the summer) than ecologically- and economically-minded people who prefer to save energy. There's never any kind of democratic system for setting the thermostat, plus different people have different comfort levels.

If the neighbors don't like high utility bills, then they should stop using so much energy. There's nothing requiring them to keep it as warm as they do: it's not hard to put on some warm underwear.

> what you did is forbidden

In law? Tenancy agreement?

isn't insulation a thing anymore?

I don't actually understand the "illegal" argument.

Illegal in what way?

because of what the other comment said and because this argument makes no sense

> what you did is forbidden because it means your neighbors just have to heat more since their walls will leak heat to you

if you don't turn up your heater, your neighbors don't have to heat more, the air in an insulator, some heat will leak in your apartment, but will also leak back to theirs, it will soon reach an equilibrium, unless you keep the windows open to cool down your apartment or turn on the AC.

Anyway most of the heat that leaks is through the heating pipes in the walls, it would leak anyway, the temperature of the wall is always gonna be lower than the water in the pipes. So you are heating up your neighbors walls even if your neighbors are keeping the heating on.

Why would you insulate inner walls of a building?

So you don't have to hear your neighbors having sex.

Thermal and acoustic insulation are a different thing.

To avoid heat transfer between rooms that people want at different temperatures

Fireproofing? (Really fire resistancinh)

For whatever reason, I’m in the same situation, but in a relatively modern building where the hallways are warmed and slightly positively-pressurized for fire/smoke mitigation, so there’s a constant slight heat source coming in from the hallways. Combine that with good insulation, some base loads and southern exposure and we go all winter running the hvac for just a few hours.

It would be too hot if we ran the heat.

This is in Toronto where it’ll average a bit colder than continental Europe.

This doesn't add up with the way thermal mass or thermostats work..

the unheated unit wall will have less heat, but the thermostat is checking the air, which is protected by wall.

The above poster didn't have his neighbors turn up the heat for them to be comfortable.

I used to live on the 3rd story interior apartment; had to turn the ac on early in mild winters (southeast us) because one of my neighbors must have enjoyed living in a tropical house.

Can you explain in physics/thermodynamics how adding more heat to a building through consuming fuel would result in less fuel consumption?

That's why in a lot of apartment buildings the heating bills are actually averaged between flats - so one person using nothing will not make their bill drop to zero.

It’s usually because the hassle and account fees from submetering doesn’t make up for the conservation it encourages.

It’s a huge waste of money in smaller residential units where people don’t have a garden or car to wash. And sometimes not even responsible for their plumbing or appliance choice/efficiency/maintenance.

Paying $x/month in account fees and meter reading means someone else burns some other resource while you work to conserve (if one even bothers).

Massive disincentive to reduce your energy use, bad idea

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