Hot weather buildings

[nancylebov]

ozarque and bradhicks have both written about buildings that handle hot weather better than most of what we've got. They both cover similar ground, but the former includes the importance of a culture where it's legal and safe for everyone to sleep out of doors in the summer and the comments to the latter have a discussion of hot weather and tall buildings that I haven't seen elsewhere.

Without getting into the question of how blame should be allocated between buyers, developers, and building codes (unless you really, really want to), what can/should be done to improve the existing building stock? Or the beliefs, behaviors, and laws which make it not feasible for people to sleep out of doors in cities?

One side note: Trees are lovely, and big trees shading a house are lovelier, but trees near a house in wildfire country are *not* a good idea.

Comments

[chickenfeet2003.livejournal.com]

I think the really difficult bit is to design buildings that handle hot and cold weather well (and don't collapse in earthquakes!). I've experienced buildings in, for example, Thailand and Queensland that were great in hot weather but I'd hate to have to live in them when a blizzard was raging. On balance, caves seem about the best all round solution.

[src.livejournal.com]

Must somewhat disagree here-- the key to handling both hot and cold weather well in a building is a combination of thermal mass and thermal input regulation (inSUlation and inSOLation).

You essentially want it to be hard for the environment to swing the building itself more than 20 degrees or so off-kilter compared to the temp you want. Even in a 'conventionally built' home (a phrase I will deliberately not expand, it varies so much!), building a thermal mass pool underneath can really transform one's heat/cool management. Thermal mass pool is basically digging a pit under one's slab, insulating it from the surrounding earth, filling it with coarse gravel (for stone mass & air space), and ducting in and out of it. Done right, it will stay at about 55 - 60F in temperate/hot climates, and not drop lower than 50 - 55F in cold climates. In each case, giving one a nice reservoir of pre-warmed or pre-cooled air with which to circulate. Requires well-insulated home, of course, lest one transform house air at a rate too great for the thermal mass pool to regulate.

[chickenfeet2003.livejournal.com]

I like that. It's roughly equivalent to having a "slave cave" for the house. How does it work for higher density housing though? If I look at the overall energy/environmental impact equation, having people living in dispersed single family dwellings is a huge problem regardless of how individually efficient those units are.

[src.livejournal.com]

Higher density housing can be reduced to the same problem, given that it's a shell and the inside of the shell. Can't regulate how folks 'spend' their energy, but if you hook ductwork into it and do common heat/cool, you're good. Of course, most apartments where we are have their own separate little wall furnace (mild CA climate), and back east a converted duplex/triplex would have separate furnaces down below.

As long as you have good wall, roof, floor insulation, you'll actually come out ahead as long as ventilation works for each unit. We had nice warm floors in winter on our 2nd floor apt, from the heat from folks below us. In the summer, we shielded them (alas!) from the hideousness of the flat black tarpaper roof with uninsulated, no-soffits attic. Bleeeargh. Don't miss that at all!

[dr-zrfq.livejournal.com]

I will definitely keep this in mind for when we build our own. Unfortunately it doesn't work quite so well in our current neighborhood -- go down 4-5 feet and you hit a 25 foot thick granite slab.

[src.livejournal.com]

Oh, hey, a thermal tie-in to a huge slab of underground granite is a *great* thermal mass builder! Hell, you could pour your basement floor right on top of it.

Unless a huge mass of it sticks up into the sun right near your house, that sucker will definitely shield you from the slings and arrows of puny surface temperature phenomenon.

If your frost line goes down as far as the slab, though, you'll want to insulate your basement or thermal gravel pit FROM the slab, else you'll never get the house warm in winter. Sink an insulated shaft full of gravel down to it for summer cooling, though if your frost line goes down to 5-feet, you probably don't get enough 'summer' to really care! Even in Dexter Maine, 45th parallel, our frost line (with snow) went down only about 14 inches, though we did lose water one winter when lack of snow cover drove the line down past 20 inches where our water pipe was laid.

[pecunium.livejournal.com]

Actually, some of the blame has to be laid at the feet of developers, at least in Phoenix, where adobe buildings are forbidden.

In LA I can see where this is a reasonable things (what with the tremulous earth) but desert buildings really do benefit from insulation. The power costs would drop dramitically with some subtle changes in default architecture (the Gamble House, in Pasadena, has some swell features, which keep it quite habitable year round, without air-conditioning).

Thicker walls are probably the easiest thing to do. With re-bar and concrete this can even be done in earthquake country.

Trees... I have to disagree. Dense plantings in fire country aren't so great, but they have enough benefits to outwieght the general risk of fire. So long as the brush isn't dense, and people aren't building on high risk terrain trees benefits (IMO) outweigh the risk of fire.

At least here in LA, the risk isn't trees, it's the uncut brush, and lack of trees (the two types of vegetation are scrub, and upland oak woodland. They former is what we mostly have, it burns with a terrible fury. The latter is what we want, it burns quickly, but at a much lower heat. the problem is the latter needs a regular burn, the latter thrives on irregular, and furious, fires.

Shading the streets is a huge benefit to keeping a city cool.

TK

[nancylebov.livejournal.com]

Actually, some of the blame has to be laid at the feet of developers, at least in Phoenix, where adobe buildings are forbidden.

Wouldn't that be the blame going to the regulators? Admittedly, they're probably in the pockets of the developers or possibly the construction industry, but aren't they responsible for what they do?

I should have been less definite about the trees. I've heard of regulations limiting how close trees can be to houses, but for all I know, they're ill-conceived.

[pecunium.livejournal.com]

The regulators are guilty, insofar as they listened to the agents of the developers (in the 60s) who told them adobe was unsafe, and got it banned.

Prior to that, adobe was legal.

TK

[src.livejournal.com]

A good part of tree issue in hot, dry places is that folks tend to plant trees that thrive in hot, dry climates-- like Eucalyptus, for instance, here in CA (non-native). A common desert tree adaptation is to be highly resinous, to slow evaporation of scarce water. Resins burn most wonderfully and fiercely. Etc.

BTW, as long as I'm here-- I don't pop up much to say things, but in general I really appreciate the level of thoughtful stuff that you post, and follow yr pointers pretty regularly. Sorry not to be more vocal or frequent in praise. Thanks much.

[avram]

Does anyone else think it's just a little funny to see a guy with an icon that makes him look like the devil, complaining about the heat?

[nancylebov.livejournal.com]

I'm so used to Brad's icon that I hadn't even thought about it.

[wings13.livejournal.com]

I've thought for the past few years that it would be nice to have a sleeping porch, such as they had in the old days...

[lightningb.livejournal.com]

Problems with sleeping "outside" in the summer:

• Fear of crime
• Fear of heights (for high-rises)
• Bugs

How rational these are is a topic for debate.

Something to keep in mind is that buildings are valued by the square foot. "Single use" areas like sleeping porches or garages are much less valuable than interior space. Most of the garages and screen porches I've seen around here have long since been converted to interior space.

In terms of design, architects tend to be *very* conservative. The only way you can get financing for a building is to convince the bank that they'll get their money out of it if you go bankrupt. Radical designs are Right Straight Out, unless you pay cash.