[jetgraphics]

Starting in the 1970s, I became interested in "alternatives" to the standard "Code" house. I read all the books I could find. Did thermal calculations for fun. I was even a charter subscriber to Rodale's "New Shelter", which featured articles expounding all the trends and ideas related to energy efficiency, solar (passive and active), and common sense.
To make a long story short, the overall consensus gleaned from many articles and user reports was that SUPERINSULATION was the best tactic for building a frugal shelter.
An example from the 1970s was the Saskatchewan Conservation House, with R40+ walls, and R60 ceiling.
http://esask.uregina.ca/entry/energy-efficient_houses.html
http://greenedmonton.ca/energy-answers-01

Such houses can be improved with an addition of thermal mass, to moderate temperature swings from sudden changes. (Though most think of concrete and stone, the best thermal mass is encapsulated water - such as barrels of water.)

However, there is a problem in hot/humid climates.
http://www.greenbuildingadvisor.com...ssivhaus-standard-north-america#comment-45053

Taking a cue from indigenous architecture in hot / humid climates...
The solution for when conditions become miserable - and especially when there is no power for A/C - is to copy the example of the jungle hut - just a roof and maybe bug mesh - and little else. The obvious question is : how does one build a superinsulated jungle hut?
Answer : you don't. You place the "jungle hut" on top of the superinsulated house.
Make sure your design has a nice, flat deck on top. That's where one can set up a belvedere, loggia, sleeping porch or whatever you wish to call it. Your roofing is a separate (and uninsulated) structure over the deck - providing shade and protection from rain. (Or the roof deck could be shaded by a pergola / trellis system, with bug mesh suspended underneath. A "Green hat".)
There are minimal walls - perhaps only a railing - and support for insect screening - and little else. If you built your roof deck from a nice durable material like fiber reinforced concrete, you will have an excellent weather proof place to while away the hot times. IMHO, a shaded roof deck is far superior to a backyard deck or a front porch. It's higher up, in the breeze, has a great view, and if one wishes to set up a hammock and sleep, it's not visible from the street below. Savvy owners / builders might also run plumbing to a "summer kitchen" and now you can have cooking AND dining al fresco. Add a lavatory for convenience, and perhaps a hot tub, for tubbing under the canopy (or stars if you wish). Make it a complete living area - run a connection for your TV / entertainment system - and you can kick back and enjoy the night time coolth and hum "Up on the roof" under your breath. Oh, and if Mother Nature hasn't turned on the breeze, install a few ceiling fans to do the job.

(P.S. - the Architectural establishment considers superinsulation to not be cost effective, citing the inherent losses through windows. Even the most high tech windows represent a substantial "hole" in the wall. However, one simple solution is operable insulated shutters, closed during the night or when there is an extreme temperature event. Such shutters can be designed so that they can incrementally close off the thermal "hole" and still allow some light.)

 

[Daisy]

got any pictures??

 

[jetgraphics]

got any pictures??

Sorry, I keep getting errors when I try to attach a jpg.

 

[jetgraphics]

Addendum:
If you install operable insulated shutters, and use them, then it may be reasonable to drop expensive high tech windows from one's design.
The benefit from an R2 to R5 upgrade, is overshadowed by an R21+ shutter.

 

[goose3]

(P.S. - the Architectural establishment considers superinsulation to not be cost effective, citing the inherent losses through windows. Even the most high tech windows represent a substantial "hole" in the wall. However, one simple solution is operable insulated shutters, closed during the night or when there is an extreme temperature event. Such shutters can be designed so that they can incrementally close off the thermal "hole" and still allow some light.)

I think this "establishment" should learn a bit more about how to build an energy-efficient home. And using examples from the 70s precludes all knowledge and building tactics which have emerged since then.

Windows should not be placed on north sides of the house (northern hemisphere--reverse for S.H.) as they gain no heat from the sun in the winter; only south-facing or west-facing windows should be used. These windows should be shaded in summer (there are passive ways to do this).

Further, and this is not understood by a lot of people including, apparently, the "establishment," up to half the heat loss in a house during the winter can be due to excessive air exchanges. A typical home has air leaks, from cracks around windows and doors, holes in the building envelope from electrical outlets and ceiling lights, vents to the outside from kitchen, bathrooms and dryers, and just small cracks in the building construction that can't normally be avoided. This is why homes are usually wrapped in Tyvek or other similar housewrap, in an attempt to reduce that.

If you live in cold winter climates, you can detect a "leaky" home by how much static there is in the winter; as cold and dry outside air displaces the warmer inside air, and then is heated, its relative humidity becomes very low. This encourages static from, well, everything. But if you can control the air leakage, you can maintain a higher indoor humidity which not only is more energy efficient, it's much more comfortable and allows a lower indoor temperature--which saves energy. A dry house feels cold, even if it's at a reasonable temperature, because the dryness encourages perspiration to evaporate--which cools.

A properly-constructed superinsulated home will essentially heat itself from body heat, cooking heat, electronics heat, shower heat, and, if they're used, incandescent-lamp heat. But a leaky home can never do that.

Two questions remain: How do you create a tight-envelope house, and how, then, do you ventilate it as a too-tight house will not only develop high levels of indoor air pollution, humidity levels in the house will shoot up?

Different building styles can seal a home with what is effectively the vapor barrier protecting the insulation from moisture moving into it and condensing, with ruinous consequences. Using concrete for walls (using insulated concrete forms; example) can work if the R-value is high enough; conventional construction can use sheet plastic or visqueen under the drywall on the inside, on all exterior surfaces including ceiling; newer spray-foam insulation can act as its own vapor barrier.

In conventional construction, sole plates sit on foam pad, cracks are caulked, insulation is used *everywhere*, airlock vestibules are designed into the home, and the house is sealed to within an inch of its life.

It's not hard to seal a home; it just takes some effort, but that effort must come at construction. It's very hard to retroactively seal a leaky home. Some leaks can be eliminated, but not all.


Once a home is sealed, it must be ventilated. There are a variety of heat recovery ventilators on the market whose purpose is to exhaust moist and stale inside air through a core which transfers as much of that heat as possible to incoming, fresh air, so as to recover as much energy as possible. Some technologies, such as the Lossnay Core, can recover as much as 83 percent of the temperature difference between inside and outside air. For instance, if inside temps are 68 and outside temps 20, the ventilator will raise the temperature of the incoming air to 60 degrees.

How is that possible, when it looks like the two airstreams, at best, should simply average out? Lossnay cores transfer heat not only conductively, but also by allowing moisture to move from the outgoing airstream to the incoming air stream. Moisture carries a large amount of heat energy--this is why, during humid periods in the summer, outdoor temperatures don't moderate much at night--and so if that moisture can be partially transferred to the incoming air stream, it greatly raises the temperature of the incoming air.

But not all the inside moisture is transferred, which is why the ventilator removes enough moisture from the air that it doesn't build up in the house.

That heat exchange ventilator can be run on a timer or, as in the case of my home, it is on a humidistat; when the humidity in the house rises a bit, the ventilator kicks on and runs until the humidity falls.

The numbers above--raising outside air at 20 degrees to 60 degrees using inside air at 68 degees--come from my own unit which I tested when it was installed by placing digital thermometers in the air streams.

All of the above comes from my own experience building a home that is not quite superinsulated. At the time, banks would not provide mortgages on homes with no high-capacity furnace (which is one way to pay for insulation--you don't need to heat the house as much so a furnace is unnecessary). You simply have a small electrical resistance heater for the few times when temps fall so low for a period of time that the normal heating mechanisms like electronics heat can't keep up. But the banks wouldn't go for it.

Still, with my R-25 walls, R-54 attic, excellent windows, tightly-sealed construction, and a heat-exchange ventilator, my heating bill during the coldest month two years ago was $80. I'm in Wisconsin where, you may have heard, from time to time it gets wintry. I have never had static in my home in the winter; it's comfortable as the humidity levels are at a reasonable point, so we can keep the temperature at 68-69 degrees and it's very nice.


In the end, for me, the closer I could get this house to superinsulation, the better. I'm "insulated" from energy price spikes, "insulated" from supply interruptions, and that's one of the best preps I can think of.

 

[Meat Guy]

Great post Goose3.
When energy prices double or tripple, people will be VERY interested in superinsulation.
Thermal mass inside and sufficient insulation outside the mass makes a home that take very little to heat and cool. If part or all of the home is below grade, that helps much more.

 

[The Heretic]

The house I am buying will eventually need a new roof. I plan on a sheet metal roof with as much insulation as possible under it. The house is already well insulated, but the roof insulation makes a difference both in the summer and winter.

Insulation is good. The house I am leasing has fairly good insulation. We had 100+ temps last week and I would close up the house tight and each room too. I would cool down my bedroom as much as possible overnight and then shut it tight. The house itself could be as much as 20 deg below the outside temps when I got home, which made it tolerable (last week I had my SIL install the window A/C to help and now I leave it on if it gets hot again).

But I think even better than insulation is having the house be below ground or earth bermed. The earth itself at those depths stays pretty cool in the summer and warmer in the winter, so you are not fighting air temps near as much.

I plan to build a root cellar with a "safe room"/bunker/shelter at the back of it (hidden) and this will be mostly underground (into the side of a slope).

Of course, you still need to insulate, but between the earth and the insulation you pretty much have it made.

 

[jetgraphics]

Window placement for "heat gain" is a cold climate issue, not applicable across the nation, nor a major issue in a superinsulated structure, where waste heat can offset losses. (See: thermasave.us, for anecdotes on Alaskan houses built with fibercement and foam SIPs)

IIRC, the Saskatchewan house occupants major issue was waste heat from using appliances like the oven. In their opinion, they needed some means to moderate temperature swings. {According to the article I read, the occupants spent $0.15 on heating for the first year... it was the amount consumed when they tested the furnace.}

As to energy recovery ventilation systems, they are important in any house that has minimal infiltration.

The Mitsubishi RenewAir (Lossnay) model is excellent.
There's also a passive dehumidifier available that doesn't rely on a heat pump.
http://semco-ms.semcoinc.com/News.nsf/FE3147A4A6AF385586256DF20054896F/$File/PVS_Product_Sheet.pdf

Bottom line: superinsulation + insulated shutters is prudent.
And for hot / humid conditions, add a "jungle hut" on top... just in case.

 

[strvger]

hmmm... i limit my west facing windows due to most of the cold winds and blizzards coming from the west and north. -20 with 15+ mph winds quickly robs heat from those west facing windows.
but that's just me.

 

[Kipper]

Great post Goose3.
When energy prices double or tripple, people will be VERY interested in superinsulation.

When? have you seen the price of energy recently (Luckily for you you live in USA, come to Australia where we get to pay 28c a KWH for electricity....)

I am looking forward to building a house at some stage in my life, and when I do I am to make it a passive house (ie, no heating or cooling required)

A component of it will be 1 super insulated living area that has a split system in it, should some silly sod decide to leave the door open and loose my heat.

I am looking at either ICF or reverse brick veneer, but we will see.

I want it to be 2 stories, with a concrete roof/floor for thermal mass.

 

[jetgraphics]

got any pictures??

Irregular octagon, surrounded by trellis array, "jungle hut" covered roof deck. Any resemblance to a castle keep is purely accidental.

 

[fullmetal]

super-insulation may be the easiest most useful idea in sustainable housing ever

 

[jetgraphics]

But I think even better than insulation is having the house be below ground or earth bermed. The earth itself at those depths stays pretty cool in the summer and warmer in the winter, so you are not fighting air temps near as much.

Going below grade can be a problem - especially if there's a risk of flood or a high water table. As Charlie Wing said, "A basement is a swimming pool, you spend a lot of effort to keep dry." (or something like that).
And you may wind up needing a dehumidifier to stop mold.

Subsoil temperatures are the result of heat flows. Presuming that you will be kept "warmer" by soil is a mistake. It only lessens the temperature differential. You will still need insulation - and a lot of water proofing, etc., etc.

The image from the previous post shows the garage at ground level. That level has utility functions. The next level up are the bedrooms, and the top level is the main level. Raising the insulated living area has several benefits:
[] Flood safety
[] Multiple exits above high snow drifts
[] Security
[] Air locks

Having the main level on top makes it easier to incorporate solar appliances, skylights, etc. And there's a better view from on high.

 

[goose3]

super-insulation may be the easiest most useful idea in sustainable housing ever

When I first looked into this (and I've been learning about superinsulation since about 1981), I talked to my wife about possibly building an underground or earth-bermed house.

Her response? "I'm not living like a mole!"

Superinsulation overcomes that problem; a superinsulated house can look and live just like a conventionally-constructed house.

**************

Too many people, IMO, when they think about the issue of maintaining heat in a home, approach it from the supply side. That is, they're trying to figure a way to get cheap heat into the house.

In my view, that's the wrong way to look at the problem. The key issue should be figuring out how to prevent the heat from leaving, instead of focusing on how to get more in.

And if you think about it, doesn't it make more sense to focus on keeping the heat in, instead of focusing on how to keep getting more heat?

 

[Pinhead]

Earthship. That is all.

 

[franklin]

Back in the 80s I built a heat exchanger for my dryer. I could see a noticeable drop in my heating bill. I haven't checked to see if any are commercially available today but that would be something to check.

 

[MattB4]

...
Taking a cue from indigenous architecture in hot / humid climates...
The solution for when conditions become miserable - and especially when there is no power for A/C - is to copy the example of the jungle hut - just a roof and maybe bug mesh - and little else. The obvious question is : how does one build a superinsulated jungle hut?
Answer : you don't. You place the "jungle hut" on top of the superinsulated house.
Make sure your design has a nice, flat deck on top. That's where one can set up a belvedere, loggia, sleeping porch or whatever you wish to call it. Your roofing is a separate (and uninsulated) structure over the deck - providing shade and protection from rain. ...

Uhh... the reason that the natives built Jungle huts was because this was the building materials they had, adapted to their environmental needs. They were not very good structures for long term protection of furniture and household goods. Leaked they did.

Your idea of a lightweight roof on top of a flat roof building would not meet hurricane or heavy winds building codes. The flat roof of your main structure would be prone to leakage failure also.

Super insulated structures and their faults have been detailed although I think many believe that a air exchange system overcomes them. I do not agree. There is a law of diminishing return when it comes to making a structure too insulated. It is a balancing act of heat exchange, moisture exchange and pressure equilibrium. Not to mention practicality of building and costs.

In earth structures are also a problem because they need to be insulated against the thermal transfer to the lower earth temperature unless that temperature is one you are happy with. Say a fairly constant ground temperature of 55F. If you want your structure warmer you need to overcome this temperature difference. Year round heating would be required.

Building homes that match the environment where they are situated has been a major push for generations. There has been a lot of trial and error. A solution that works for one climate may not work for all.

 

[goose3]

Back in the 80s I built a heat exchanger for my dryer. I could see a noticeable drop in my heating bill. I haven't checked to see if any are commercially available today but that would be something to check.

Oh, they're available. Tons of options. Google "dryer vent heat recovery".

Sometimes in homes that are very leaky and drafty, people would actually direct the exhaust hose directly into the home to help raise the humidity in addition to supplying the heat. Just another form of humidifier.

 

[goose3]

Super insulated structures and their faults have been detailed although I think many believe that a air exchange system overcomes them. I do not agree. There is a law of diminishing return when it comes to making a structure too insulated. It is a balancing act of heat exchange, moisture exchange and pressure equilibrium. Not to mention practicality of building and costs.

Well, the air exchange system in my home has overcome whatever "faults" there are with superinsulated systems. And the only "fault" I've ever found with a superinsulated home is that it needs to be ventilated.

But here's the cool thing about that: I get to control the ventilation rather than having it completely out of my control, which is what you have with a leaky house.

What I've found is that the more a person has a vested financial interest in people not choosing superinsulation, the greater their criticism of it.

As I noted earlier in this thread, my heating bill is tiny compared to what people normally have. I live in Wisconsin. Gets cold here. An $80 heating bill in the dead of winter is a lot of money saved.

Then again, some people would rather choose what appears to them to be a safe conventional approach despite much higher ongoing costs. More power to them. Meanwhile, I'll dedicate my savings to other uses than supporting the utility companies.

 

[MattB4]

Well, the air exchange system in my home has overcome whatever "faults" there are with superinsulated systems. And the only "fault" I've ever found with a superinsulated home is that it needs to be ventilated.

But here's the cool thing about that: I get to control the ventilation rather than having it completely out of my control, which is what you have with a leaky house.

What I've found is that the more a person has a vested financial interest in people not choosing superinsulation, the greater their criticism of it.

As I noted earlier in this thread, my heating bill is tiny compared to what people normally have. I live in Wisconsin. Gets cold here. An $80 heating bill in the dead of winter is a lot of money saved.

Then again, some people would rather choose what appears to them to be a safe conventional approach despite much higher ongoing costs. More power to them. Meanwhile, I'll dedicate my savings to other uses than supporting the utility companies.

Glad your home is working for you. However it is in Wisconsin that has different climate than others have. Using a safe approach to things means that the odds of ending up with a home that lasts and is salable, is higher.

I have no vested financial interest in being against super insulation. I just look at the science of heat transfer and the requirements for practical, comfortable living envelopes. One of the problems with most energy saving ideas is they cost more to implement (or they are less desirable) than more common approaches. I have seen folks that spend ten of thousands to save $50/mo on a energy bill. Hardly economical.