OT Which direction is your ceiling fan SUPPOSED to run?

Give it a rest already. Rour totally unballanced psyc is showing!!

Those keyboard commandos sure can waste a lot of your time.

Part of the def'n of Totalitarian is trying to suppress opposing views.

So are you saying a heat pump can change the laws of physics, but just a little bit? Thanks, I must have missed that class.

Amazing pattern made up of 8 pieces. Laid out on a floor around 30 by 50 you just don't 'notice' that pattern.

I didn't paint the roof, it's tile and its color is its color.

I painted the walls which receive oblique sunlight and sometimes no sunlight with the eaves shading. I only experienced 'cooler' HOT temperatures in the garage and the fact our inside home stayed a 'tighter', and lower, average when we weren't running A/C etc.

I would expect that during the day a white roof would be cooler. Having a superheated black structure above your head just can't be as cool. No aspersions on life style meant.

Right. My problem is that my house is environmentally incorrect and far from typical. There's no attic. The roof and ceiling are non-insulated 2x T&G pine[1]. There's considerable (double pane) glass in the walls. Add two single pane sliding glass doors and two single pane French doors. Air leaks around some doors and windows. With so many leaks, my rule of thumb is that the house temperature never goes above or below about 20F from the outside temperature, even when running the woodburner. Such a house would not be practical in any extreme environment, but reasonably functional in a dense redwood forest, where the trees moderate the temerature swings. As you note, the door/window temp regulation method is functional for most houses. However, my efficiency, as indicated by the equal temperature time, is far from optimum.

[1] The roofing is 20 years old and probably has another 5-10 years of useful life reamining. I plan to insulate the roof when it is replaced.

A few web pages recommend painting your tile roof white: Of course they're selling the paint, which does tend to bias the point of view. I'm not sure it will make a difference or an improvement.

There are charts available showing the SRI (solar reflectance index) but I don't want to dig through them to determine if coating your tile roof will offer any benefits.

A roof with a clean, smooth "cool color" surface, such as a cool red tile, can reflect about 35% of incident sunlight (R = 0.35) and emit thermal radiation with 90% efficiency (E = 0.90). This

red tile is much warmer than the bright white roof, but still cooler than a standard red tile (R = 0.10, E = 0.90, SRI = 6,

That's nice, in the woods.

When we refurbed our business building, and redid the flat roof, we added a roughly 4" thick thermal insulator, and painted that aluminum. The ceiling in my office stays just about the seme temp as the floor.

Not at all. You're welcome.

There is your fallacy. The heat produced at the hot coil is largely balanced by the cold at the cold coil (with the exception of the power drawn from the outlet which is not trivial) but the cold coil does not cool the air as much as the hot coil heats the are. Most of the heat entering the cold coil is used to condense the water which does *not* cool the air. The opposite of evaporative cooling is condensative heating. Heat has to be extracted from the moisture to condense it which does not cool the air while that same heat at the hot coil *does* warm the air.

Ok, but not a useful point.

I'm having trouble following your statements because I can't tell what "drawing" and "heat input" refer to. Are you saying the unit draws 280 Watts from the power line? I don't really see where you are going with this and I certainly don't see how you can compare the two types of units in this vague way.

Ok, but until you understand the real heat flow, you can't say you

outside and you run your dehumidifier you will be heating the air which

humidity then a dehumidifier may be the right choice.

I think Ralph's point is moot because AC units don't cool "only a little below room temperature", but the concept is valid. Moisture condenses only when cooled below the dew point. It doesn't even depend on the temperature of the coil, but rather of the air passing over the coil. If the air never reaches the dew point (either because the coil is not that cold or because the air moves over the coil so fast) no moisture will condense.

Those *are* the laws of physics.

What about suppressing idiotic views? Is that totalitarian or just hard to resist?

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You ARE Sloman!

What a mess! That doesn't even look structurally sound, way crazy unsuporte d bump-outs, and roof purlins resting on top of that 2nd story balcony with no vertical support for the balcony (that I can see). And is that redwood siding and beams? Shame on you!

What exactly is "cool red tile"? What is different in it's construction from hot red tile?

I looked at the reference and I'm not sure I understand what they are measuring. I learned many years ago that a surface can not have different abilities to absorb or emit heat. If it did it would spontaneously warm up or cool down. But I suppose it can be a matter of different rates of emission/absorption at different wavelengths. Solar is IR, visible and UV. Once warm, the heat from a surface would be IR, possibly long wave IR. So I suppose you can achieve an advantage by having a low coefficient at the shorter wavelengths and a higher coefficient at long wavelengths resulting in higher emissivity at night and a lower absorption during the day.

Thanks. I wanted to buy a house "away from it all" in about 1974. At the time, only about half of the houses in the neighborhood were occupied year round. The rest were vacation houses, Section 8 housing, and methamphetamine factories. It was common for the dogs to sleep in the roadway. That worked well until the 1990's, when living in the trees was deemed fashionable that everything I was trying to get away from moved in next door. That's not really bad news as the local infrastructure has gradually improved over the years, and rising home prices has introduced a better class of residents. Be careful. This type of progress can also happen to you.

Hmmm... that's about what I would expect from a concrete slab floor. The thermal sink it provides is substantial. If it has cold water pipes running through it, even better. You might try the same test with the HVAC and circulation fans turned off. I did that once (when I was complaining about the air conditioning not working) in my palatial office (thin carpet on slab with a 3ft suspended ceiling with minimal insulation). I vaguely recall almost no differences with the fans going, but about 15 or 20F difference after about 2 hrs in still air. This is measuring air temp with a thermocouple probe, not an IR thermometer. However, we had a new roof installed late last year and I should probably retest this again. The new reflective roof is noticeably better than the old asphalt black roof.

Thank you. I'm honored that you would take the time to offer constructive criticism. Unfortunately, I can't take credit for most of the old construction. I didn't build the upper floor. When I bought it in 1974, the living room (the glass on the left) was supported by 20ft long 4x4 posts, with marginal cross bracing. The front door was misplaced on the floor of the living room, horizontally mounted as a sliding door. There was also a small tree growing through the floor and roof. I'll see if I can find some photos. The one of me chain sawing the tree next to my desk should provide some entertainment. Over the last 40 years, I added a perimeter foundation, added the downstairs rooms, changed the roof line, added decking, added retaining walls, etc. In effect, I built the house starting from the roof, and worked my way down.

It survived the 1989 Loma Prieta earthquake without any structural damage. Most of the inside damage was caused by the huge pile of trade magazines I had piled up in the kitchen. I was walking on a thick layer of magazines for several weeks before I was able to haul everything off for recycling. Everyone in the neighborhood with a chimney had them fall apart. Several houses slipped off their foundations. I only lost about 40ft of triple wall 8" flue pipe that collapsed and rolled down the hill. The loss was not from the quake, but rather from theft before I was able to retrieve them. Oh, some cracked drywall, and a slight tilt in one part of the floor.

I guess I should point out that one of the major problems with living in the hills is that there are hills. Houses prefer to sit on level lots. There are a few of those sitting on river silt, but most of the lots in the area are on the sides of hills. I find it amusing that developers first level a development, remove all the trees, and build flat foundations. Residents then replace the trees and "landscape" the property effectively putting back the hills.

I'm more worried about some of the big 150ft redwood or fir trees falling on something than the house sliding down the hill.

The contractor that built most of the neighborhood is still alive and only slight less irritating than he was 50 years ago, when he built the house. We've had a few loud convesations, where I asked numerous "what were you thinking when you did..." type questions.

I would have liked to run things in a straight line, but there were too many trees and stumps in the way. It was easier to go around.

Yeah, that is bad but again is part of the original house. The roof over the balcony is held on with extensions from the roof beams, making suspending the balcony from the roof beams also a bad idea. I had planned to add some additional vertical support, but never got around to it. Next year, maybe.

Redwood siding, Douglas Fir beams. There are a few redwood floor joists which I inherited from the previous owner that I didn't consider worth removing.

Thanks again the useful insights.

Really? Can you say cantilever?

I would be a lot more worried about a tree falling on it than it falling of its own accord. A friend of mine who lived in a giant redwood forest had a tree next to his house over 4 foot in diameter he referred to as a baby. Seems that with a heavy rain there is the chance the hill will slide and the trees uproot. It only has to happen once and many tons of lumber lie on top of your house.