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> Everyone I know who has built a house has thought very much about sun, season and temperature.

I've lived in houses that certainly did not take into account sun, season and temperature. I learned a lot from that experience. My current house is optimized for it. I've learned a few more things about it, and could do better.

> the idea that it has something to teach modern architects and builders is pure fantasy

Not my experience with architects and builders.

For example, how many houses have a cupola? They're common on older homes, but non-existent on modern ones. What the roof does is accelerate the wind moving over the roof, then the air vents in the cupola let the wind through, which sucks the heat out of the attic.

Another design element is eaves. Eaves shade the house in summer and don't shade it in winter (for more heat gain). Eaves also keep the sides of the house dry, which means your siding and paint and window frames last a lot longer. Mine are 1.5 feet. Most houses around here have tiny or even non-existent eaves.

The advent of air-conditioning is when architects stopped paying attention to the sun.

> For example, how many houses have a cupola? They're common on older homes, but non-existent on modern ones. What the roof does is accelerate the wind moving over the roof, then the air vents in the cupola let the wind through, which sucks the heat out of the attic.

This one is genuinely obsolete. With modern techniques, it’s straightforward to build a reliable unvented attic, and there are few if any climates where a vented attic makes sense. There are plenty of climates where a vented attic, even a nice one with a cupola, is massively inferior to an unvented, conditioned attic.

Seal and condition your attic. Put on a decorative cupola if you like. If you live in a place with heavy snow load, you vent a small gap between the top of your attic and your roof surface to help keep the actual roof surface cold enough to avoid melting the snow.

I've been in an attic many times on a sunny day. The heat in the attic is well above what it is outside. I'm highly skeptical that an unvented attic is going to keep a house cool in summer.

Me too. But have you been in a competently built insulated and unvented attic? The insulation on top makes an enormous difference, to the point that the attic can usually maintain a very pleasant temperature.

While it’s true that the top side of above-attic insulation will be rather warmer than a vented attic on a hot sunny day, insulation on top of your attic also tends to work rather better than ceiling insulation. And there are plenty of other benefits to an unvented, insulated attic.

Interesting! But having a sealed attic makes me concerned about mildew. Ventilation is needed to keep the moisture out.

Au contraire.

If you live in a climate where the outdoor air is generally fairly dry and also sufficiently warm that it spends most of its time above the interior dewpoint, then fine. You can vent our attic and it stays dry. This covers rather little of the world.

If you do not insulate at all and you heat your house when it’s cold or wet and you do not experience hot and humid weather, then there will be enough heat flow to keep your attic dry. This is generally an awful idea, but old insulated houses did work in many climates.

If you live somewhere cold and put fluffy stuff on your ceiling and you vent your attic and you have air leaks in your ceiling (hint: this is basically unavoidable) and it’s very cold in your attic, you may get condensation in the ceiling insulation or the attic. Mold time.

If you live somewhere hot and humid and you vent your attic, then you are are filling your attic with hot, humid air. Your dehumidifier or A/C will not control your attic humidity. But your A/C may cool parts of your attic, leading to additional condensation.

If you have nasty severe blowing rain, it may blow into your attic, leading to damage. This is a problem in hurricanes.

Wildfire embers can ignite the inside of your attic. You can try to use fancy supposedly ember resistant vents to mitigate this, or you can omit vents entirely.

If you seal your attic and control moisture in the living spaces well enough to avoid moisture problems and you have adequate conditioning in your attic, your attic will be about the same temperature and humidity as your living spaces, and you’ll be fine.

You can geek out at buildingscience.com. The author appears to have become increasingly convinced that vented attics are basically never the answer.

All I can say is my attic is vented, and is dry and free of mold.

Ridge vent is the modern approach, with vents and wind baffles in the eaves so air is evenly distributed.

1.5' overhang is good, 2' is ideal. Cheap builders will go 1' or even less.

Good architects still pay attention to the sun. It's often builders who are the culprits because they want to save money.

Around Seattle, modern houses are square boxes with a flat roof, and zero eaves. I watch these homes get built all the time. A few years later, I see all the water damage to the siding.

You're right about ridge vents, they behave much like a cupola, but the holes in them are too small for much airflow, and are easily blocked by debris, insects and moss.

> easily blocked

That's a concern. It may be a good idea to put a connected thermometer and hygrometer in the attic. If it is ventilating properly, the temperature and humidity should be close to outdoor values.

Forced ventilation of the attic creates negative pressure in the attic, which pulls conditioned air from the house. The additional air movement (which you should minimize with air sealing) costs more than the additional loses by the mildly increased temperature differential through the insulation.

If you aren't using A/C and have the windows open, then it only helps, of course.

The idea includes gaps where the roof meets the ceiling, so air is drawn from outside.

> If you aren't using A/C and have the windows open, then it only helps, of course.

I make use of the "stack effect" to cool the house down in the evening. Not even a fan is necessary.

One mistake I made was to not have the A/C pull from the basement, which is always 10 degrees cooler than the rest of the house.

> The idea includes gaps where the roof meets the ceiling, so air is drawn from outside.

Of course you should have soffit venting, but forced ventilation results in negative pressure, regardless of whether that venting is a cupola harnessing the wind or a motorized fan. That negative pressure will pull conditioned air out and building science research shows higher attic temperatures are better than forced ventilation.

Even better is larger amounts of passive ventilation, but if the only thing you change is adding forced ventilation, then you're creating negative pressure and this is worse if using A/C.

Unless you have really good insulation, in hotter areas, your roof will absorb a lot of heat and that gets transferred to the attic and then to the rest of the house. One of the cheapest and best upgrades in hotter areas is to have an attic fan and vents to send the hot attic air outside.

> attic fan

The cupola does that using the "stack effect" and the acceleration of the wind as it hits the sloping roof, at zero cost!

That said, I do have an attic fan connected to a thermostat. I'd rather have a cupola, though.

Building science shows this is not true if you use A/C and have appropriate amount of ceiling insulation. Inadequate ceiling insulation is helped by this.

It's not like the wisdom is lost, it's just ignored in modern builds.

All architects think about siting and solar exposure. But the builders are in charge, and they optimize for what the market responds to -- which does not always include factors like these which contribute to long-term comfort and livability.

So I would say that consumers could learn a thing or two. That said, most buyers are not buying newly-built homes, so their ability to influence the inclusion of some of these features are limited.

The industry is downstream of market demands. If customers aren't aware enough to demand smart things, builders will skip them to save money, or to optimize for more visible features. Same old story.

Even when the buyer is buying a newly built house, it's often already built or being built off of already existing plans that do not take these things into account.

Exactly. You can’t have two houses on opposite sides of the street that are perfect copies without some compromise somewhere.

> So I would say that consumers could learn a thing or two. That said, most buyers are not buying newly-built homes, so their ability to influence the inclusion of some of these features are limited.

Even then I think Americans are not at all well-versed in what makes a house a good house in terms of design or aesthetic and there isn’t a marketplace that exists to help customers shop and compare.

Today, if you’re buying a new build your only option is McMansion style or just a smaller and equally distasteful version of the McMansion. And yes they are all distasteful - it’s a matter of fact, not opinion.

So most people buying new builds end up with the same cargo culled designs. And then “architects” design more and more different versions of these horrendous designs and plop in things like Sedona Avenue near the golf course and that’s how you get suburbia. There’s never a market signal, despite the fact that we can build homes much more nicely and with techniques to be a little more naturally energy efficient and kinder on the eyes.

There is also much less competition with neighborhood design though surprisingly there have been some inroads there that have fostered some competition, but it’s mostly for now for the wealthy. I live in a neighborhood designed before cars, a neighborhood that today is largely illegal to build. But the home prices are highest here because the market is demanding this type of neighborhood - single family detached homes mixed with apartments and coffee shops and small offices and restaurants. “Mixed-use development”. It’s incredibly scarce and in most American cities it has the most expensive average real estate and tends to be the most economically vibrant. Little pockets of Europe.

Neither home builders or zoning officials have taste and because as you in my view correctly acknowledge the builders are downstream of market demands, because the market doesn’t even understand what is actually good and possible, the entire industry and government regulation apparatus is downstream of the sewer.

Or it is set out in building codes that they must design in a certain way.

In the UK that means adding lots of insulation. UK houses predominantly had a lot of thermal mass from the inner skin of the cavity wall being brick or later concrete blocks. The little wall insulation, if it even existed, was in the cavity. In a push for more insulation they switched to lightweight thermal blocks, and sometimes more insulation inside, or timber frames. All of which designed for insulation while reducing the thermal mass. No matter how much sun you put in during the day you only heat the air, which goes cold quickly. This is not the architects choice.

Architects can only design for orientation on a single house plot. In the UK they are trying to cram houses on at 50 to the acre or more due to the price of building land. They focus on best use of space, rather than orientation because of that

> > It's not like the wisdom is lost, it's just ignored in modern builds.

> Or it is set out in building codes that they must design in a certain way.

An anecdote: Two decades ago in college in the US, I knew several people doing Architecture. One day in one of their dorm rooms, one of them went on this long rant about how modern codes ignore environmental factors and just require certain things no matter the climate.

I don't know how universal her experience was, but I can see these two lines I quoted as both happening, just in reverse - the building codes are causing loss of knowledge/wisdom.

> while using large windows to capture sunlight and heat works great in the winter

That's what awnings (or solar overhangs, or light shelves) are for. You block the high/hot summer sun but let in the low/cool winter sun.

> the idea that it has something to teach modern architects and builders is pure fantasy

Isn't the idea of mcmansions that they co opt smart classic design ideas, but use them in a manner which doesn't let them fulfill their function purpose(skeuomorphism)? So someone certainly has some things to learn

> That's what awnings (or solar overhangs, or light shelves) are for.

Right, this is my point. We already think about these things.

> Isn't the idea of mcmansions

I don't think McMansions, or whatever your favorite example of bad architecture is, shows that we've somehow lost knowledge. Architects and builders are aware of all of these things, but that doesn't mean there aren't still clients who want less energy-efficient designs for all sorts of reasons, like aesthetics.

We know how to build energy-efficient buildings that are appropriate for the location and seasons. We also know how to build buildings for other purposes, and are aware of the tradeoffs in how they use more energy. Energy conservation isn't the only goal in home design.

I think the idea with McMansions is that they are just tacky. Poorly aped styles. Columns that don’t do anything and are proportioned wrong for the load they are intended to look like they carry. Complex roofs that do nothing useful but “look fancy”. 100% style over substance, but with style that snooty people look down on.

I imagine that McMansions are generally about as energy efficient (per square foot) as other contemporary homes, though.

> and while using large windows to capture sunlight and heat works great in the winter, it also leads to overheating in the summer and thus more energy for air conditioning.

A lot of contemporary energy-efficient designs slope the windows now such that light can enter in the winter but not the summer, but in the past this problem would have been remedied with awnings.

And if they are not used it's more of question of price and other available options and not "the modern architects forgot".

Making what's essentially "an insulated box" is far more universal climate-wise than most of the old methods, because what's good in summer (north-facing windows, good airflow, getting some cold from the ground) is terrible for winter and vice versa. And where it is useful, it IS used, just instead of fireplace having big thermal mass we have floor heating where the concrete floor is the heat storage (and sometimes extra tank of water)

And every method to make it "better" directly competes with "just buy more solar/battery to run heat pump cheaper.

>a major "trick" being to put them in the middle of the house rather than in the exterior wall

I vised Löwenburg in Kassel which has bedrooms with similar curtains around the bed. Much later (1891) and with other heating technology of note. I was intrigued by the fireplace design in the room immediately behind the bed. The open fire is backed by a huge granite block built into the wall. The room had a close connection to servant stairways directly down to the exterior.

The guide describe the otherwise plain room as a dressing room. It looked like a convenient place to store a lot of firewood to stoke the fireplace attached to the bed behind it to me.

It feeds into people’s desire to feel superior. “You and me, dear reader, we’re two of the very few smart ones in a sea of incompetents.”