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Heat people, not spaces (2015)

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31–40 of 335 posts

Re: Heat people, not spaces (2015)

#31
post #27

Not heating your house will make it uninhabitable within a year because of mold.

I've spent a lot of time in very old houses with limited to no modern heating, and I've never experienced this. The biggest indicator for mold is moisture trapped between walls (including animals getting stuck in walls and dying). But that's a water and humidity thing, not an ambient temperature thing.

Re: Heat people, not spaces (2015)

#32

I've been thinking about the inverse problem. I live in a very warm city. Air conditioning (cooling spaces) is the norm, but tons of money are spent with installations, maintenance and the monthly electricity bill. The new houses are designed with zero consideration about ventilation, designers seem to take for granted that you are going to buy an AC system. Oftentimes, a very simple change in the project would be en…

IMO the real solution is building materials with high heat mass (e.g. stone), and architectural designs which allow for passive cooling. This exists already, but can be expensive to build.

Re: Heat people, not spaces (2015)

#33

Earlier quoted context omitted.

Just curious, what part of the world do you live in? I've lived in cities where we experience anything between below zero to 120F throughout the year. I couldn't imagine not having AC/Heating in those areas even with more efficient ventilation/insulation.

How, that's a huge temperature gradient. I live in Fortaleza, Brazil. Temperatures here are very stable along the whole year (78F - 90F, it rarely falls out of this interval). I'm not advocating this no-AC model as a general solution though. I'm aware we're a bit lucky here. I used to live in Sao Paulo and temperatures vary more wildly there, sometimes within a single day.

Any temperate area on the planet will easily have 90-100 degree swings throughout the year. I used to live on the US East Coast and a summer high of 90-95 and winter lows of 0-5 were common my entire childhood. I moved to the midwest in the early summer and it hit 100 more than once, and it's been below 0 multiple times this winter already.

Re: Heat people, not spaces (2015)

#34

We take the general concept of heating people, not the space, to heart for our outdoor swimming pool. While most other folks heat their pool, we go ahead and swim in the cold water... but we buy everyone in the family a wetsuit. A few hundred dollars on wetsuits each year is far better than many hundreds on propane every month.

I understand the appeal of a swimming pool on a sweltering summer day but if you have to heat it...

Re: Heat people, not spaces (2015)

#36
post #27

Not heating your house will make it uninhabitable within a year because of mold.

Care to elaborate? How does cold cause mold?

Cold spots in a heated house and a lack of airflow seem to cause mold. The temperature difference causing condensation, excess moisture with nowhere to go and then mold.

Interesting whether this would happen in an entirely unheated building.

Re: Heat people, not spaces (2015)

#37

Earlier quoted context omitted.

Just curious, what part of the world do you live in? I've lived in cities where we experience anything between below zero to 120F throughout the year. I couldn't imagine not having AC/Heating in those areas even with more efficient ventilation/insulation.

Mainer checking in. Wednesday afternoon it was 70F. The next morning it was 5F Friday a snowstorm. Today -2F in AM. We all just dress in endless layers.

Worth it for the lobster rolls though, right?

Re: Heat people, not spaces (2015)

#38

I've been thinking about the inverse problem. I live in a very warm city. Air conditioning (cooling spaces) is the norm, but tons of money are spent with installations, maintenance and the monthly electricity bill. The new houses are designed with zero consideration about ventilation, designers seem to take for granted that you are going to buy an AC system. Oftentimes, a very simple change in the project would be en…

> The new houses are designed with zero consideration about ventilation, designers seem to take for granted that you are going to buy an AC system.

These are two separate problems.

In the ideal situation, you generally want the house to be fairly air tight and condition the air for (a) temperature and (b) humidity. Each of (a) and (b) are taken care of by different mechanical units: one is monitored by a thermometer and the other by an hygrometer. The latter triggers a stand alone dehumidifier:

* https://www.aprilaire.com/whole-house-products/dehumidifiers

For fresh air you have an HRV/ERV, which brings outside air (through a filter) into the house (usually to bedrooms), while at the same time blowing out stale inside air (usually taken from bathrooms and the kitchen), with the two moving through the unit so that the outgoing air tempers the incoming air:

* https://www.ecohome.net/guides/2276/choosing-between-an-hrv-...

You still have opening windows, as they're mandated for emergency fire exits.

Re: Heat people, not spaces (2015)

#39
post #27

Not heating your house will make it uninhabitable within a year because of mold.

Care to elaborate? How does cold cause mold?

In areas with coastal fog it can be the case that the cooler months with lower evaporation rates are more likely to allow spores a foothold. This is often seen in older spaces designed with passively vented kitchen and baths.

But good building design following current standards isn't going to be affected by this.

Re: Heat people, not spaces (2015)

#40
post #27

Not heating your house will make it uninhabitable within a year because of mold.

Care to elaborate? How does cold cause mold?

Moist air from cooking increases the humidity in the house. The walls of the house are cold, the moisture condenses on the cold walls keeping them damp for the entire winter.
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