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I’ve posted once before, but for those of you that didn’t see it, I’m striving for well educated DIY status, and I am not a professional by any means. But here’s my situation. Several years in the future, I plan to build a new home. I am looking for traditional styling, probably some sort of bungalow/ranch. At this point, I am gathering information and am looking for any sites/book recommendations/personal opinion or expertise etc as it pertains to passive solar construction. I am following this board intently and reading all I can. I am familiar with the DP cellulose debate, stopping air infiltration from the house into the attic, and a lot of the other topics that are hot here at Breaktime. I also intently read any posts that have to do with ICFs, radiant heat, etc. I still have much to learn. My goal is simple. To build an affordable house that makes the most effective use of the resources I put into it. And once said house is built, I would like for it to be as inexpensive to heat and cool as possible. This is why I am considering some sort of passive solar design.
The way I figure it, if I can combine some of the techniques discussed here with a design that takes full advantage of the homesite and solar gain, I win. But I’m not sure where to start. Can I build and side with claps, or will the lack of thermal mass not produce an effective end result? Do I need to consider brick or stone? Little things like these are what I wonder about.
Sorry if others out there have some expertise, but I know that Gene has some good background in this- can you offer any insight?
So, bottom line, I was hoping to start a discussion and that you guys that have more experience than I could offer arguments for or against, point me in the right direction, or offer up book ideas or websites of interest.
Thanks in advance for any assistance.
Replies
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Please, please, please use the Archives! There has been so much discussion on this Taunton could make big bucks publishing it.
*Sorry Historian, tried that. Got 15 matches. They ranged from "Mice in my insulation" (Not relevant) to Compressed earth block (Also not really relevant) 1 good match. To put it bluntly, the search feature sucks. But since I'm not welcome here apparently, I'll take my toys and play elsewhere. Thanks for the little bit of time you did take to berate me though. Appreciate it.
*hey chris... don't be so fast to take offense.....i tried the search on that too.. it does suck..but you're in the right place.. if you don't have a thin skin....here's one..http://webx.taunton.com/WebX?50@@.eeac3da/9
*Thanks Mike.
*Well, Chris, I'll jump in. First, anything you can do to ratchet up the energy performance of a house is to the good. For example, simply orienting a standard house design so that its longest, most heavily glassed wall faces south makes a huge difference in winter solar gain and enabling you to control unwanted summer heat gain. Think big overhangs.I doubt that your siding material will have much effect on the energy performance of the house, simply because it's outside the insulation. Who's next?Andy
*Chris: I've see some info, but not much, on the advantage of using an inch or two or spray-in-place urethane foam on to the sheathing. It gives you more R-value per inch the FG, lets you fill the reminder of the bay with cheap FG, stiffens up the sheathing, and most importantly REALLY makes the house tight. Or consider filling the vertical walls with urethane foam (you've got less width there) and the urethane/fg combo in the rafters. That what I did and our house (www.alaska.net/~dthomas for house and baby) was the tightest the inspector ever measured (0.07 air changes per hour) and costs only $1.10/day to heat at -25 F (-32 C). But cost it out both ways to see if the added capital costs justify the savings. One advantage for us, being in a windy place with cold winters is that we are mostly immune to power failures. 50,000 pounds of concrete radiant slab within such a tight house takes awhile to cool down. A day before you notice, 2 days before you put on a sweater. If after 36 hours, the power was still off (hasn't happened yet), I'd run the two 1/40hp circulator pumps off of a 12v-120ac inverter from the car's battery. And ignore the "don't bother me, it's all in the archives" folks. I'm not sure why they tune in - just to flame newbies or to watch Joe, Gabe, etc rant and rave? -David
*Chris:I guess Taunton hasn't gotten around to making the archives useable yet. It is too bad because there has been a lot of discussion on this over the last couple years. Let me see if I can remember some of them.In the meantime, one of the primary things about energy efficiency is to tailor construction to your climate. It isn't very energy efficient from a national perspective for you to build an arctic capable building in Iowa. The dollar and resource cost of materials production, distribution and installation is largely wasted.Second, control air infiltration and mass. That is be sure you have a house that is not too tight or it will over time make you ill. Make sure you have enough mass to hold heat, or cool temps at night, so the opposite time of day is comfortable.Then there is my favorite: Have lots of windows. I have been in passive solar and "super-insulated" homes that were in essence man-made caves. Sure they were energy efficient, but at the cost of livability. Remember the purpose of your house is to be a home.
*http://webx.taunton.com/WebX?50@@.ee9435c/0Passive Solar House PlansPassive Solar House Plans#2In what direction do I point my new house?Are all references I got from the archives. Try searching using the term "solar" then the term "passive". You get a lot of stuff to sort through. But the price makes it worthwhile.
*Dave's ideas sound good and ICFs do a similar job...near the stream,aj
*FredB. It was Larry Spielvogel who said, "Any house that has to have solar added to it was never properly designed."In 1977 the solar experts caled my Leger House a "styrofoam igloo." They forgot to mention that they had never been in it.Had I listened to people such as Mazria and others Iwould have had between 228 sq. ft. and 356 sq.ft. of glass in a south wall whose area was 336 sq.ft.And unless I added tons of concrete. masonry block, bricks, I would have had large tempareture swings and severe overheating. No doubt there are lots of bad passive solar/super insulated houses.Have you been in only the bad ones? My experiences led me to say, In a solar house the only thing that matters is solar. In a MESH house the only thing that matters is the house.(MESH means Micro Energy System House). Someday, soon, I hope, there will be no solar hoses,no super insulated houses,no double-envelope houses. There will be only houses. GeneL.
*good goal . genel...if you think back to where we started in the '70's ..we've come along way, baby..and the journey continues....
*I've been well aquainted with several "super-insulated" and/or "passive solar" and such houses over the last 30 years. Most, if not all betray the biases and narrow focus of the designer and builder. Sure, most use little energy. Sure, technically most are masterpieces of materials, knowledge and methods of the time. But, very few bring the same degree of livability as they do energy savings. Always remember for the owner this is supposed to be a home, not just a house. The goal is not to use the least amount of energy possible. It is to use the least amount of energy while maintaining comfort and livability.The single biggest failure of this style house is not having enough windows. Sure, windows cost energy. Sure, in some climates windows open the structure to more temperature variations. Sure, windows are a pain, but they are a good pain.Fortunately in most areas of the north country the term energy efficient has almost fallen from the vocabulary. That is because almost all houses are built as energy efficient as modern methods and economic analysis will allow. Where in the time you are referring to Gene energy efficiency was rare, now it is the norm. In David Thomas' area for example it is rare to see a recently built house that isn't a good blend. In fact, I am led to believe such construction is now so common in new buildings the old energy guru's have had to turn their attention to remodeling and arguing about exotic subjects to continue to earn a living.Chris: You do need to complete the education job yo have started. As you have already found there is a lot of snake oil involved in this solar business. But, ultimately it is your house and you must be comfortable in it. If that means you don't wring the last drop of energy efficiency out of the structure, that is just the price of livability.
*"passive solar" means "passive heating" but this is not possible in northern or "heating climates." One can contribute the heat of the sun to the building to reduce active heating costs but there will always be the need for an internal, active heat source. The point is, how much to spend to get the suns' heat, to retain and distribute it and to keep it and the manufactured made heat from leaving so that active heating costs are lowest.People interested in green solutions such as passive heating are usually need passive cooling. The challenge is to get the features of each without having them conflict.Getting the sun indoors for heat is easy, but keeping it out to stop heat gain in summer is an opposing requirement. Roof overhangs are the easiest and cheapest way to do this. There is a simple formula for calculating optimum overhang for maximum winter gain (when the sun is low in the sky) and minimum summer gain (when the sun is high in the sky).Low-e, argon-filled, dowble pane thermal glass windows are expensive and if oriented for optimum gain, they become a problem in the summer when you want to but can't turn them off. You can get interior surface reflective coatings to keep heat from escaping once its in but then that means your cooling loads are greater. For retention of heat, as has been said in earlier posts, mass is essential. Mass is the passive furnace. Whether it is a radiant mass or convective mass design, the essential ingredient is mass. You can't get that mass furnace from and external wall. It has to be inside the thernal insulation evnelope. This means windows are needed to capture the heat. Automatically the contrdiction appears again. Glass is the weakest part of the thermal envelope. More glass to expose more mass means summer cooling demands increase and the house's ability to retain heat is reduced (ie, increasing the area of inadequately insulated wall).Thermal bridging is a bigger factor than one might think. Wood framing members, nails and screws penetrating the envelope, uninsulated headers and plates all send out lots of heat to the outside. They also bring in heat in the summer. Passive heating mass such as concrete or stone, if not properly located and isolated from the outside, will be the worst thermal bridge of all. On the other hand, mass connnected to the earth is has passive cooling affect. So the features conflict again.So, what features can be used that are not in conflict?- Placement, placement, placement. Orientation for heating and/or cooling; wind up hill in day, down at night; southern slope; protection from weather; etc.- Roof profile - to take advantge of and or protect from local climate and house placement. Long overhangs on south and west for cooling and on the north and east sides for bad weather protection. Hip roof better than gabel; etc. Roof overhangs sized for optimal amount of winter sun reaching the windows on the east, south and west sides. Sized for minimum reach of the sun through windows in the summer.- If you can afford it, mass, but isolated from the earth and air (except where its set down deep enough to get geothermal benefits - still need insultion from air and above frost line). - An isolated exterior wall cavity sealed from infiltration/exfiltration on all six planes of the building. This means mechanical or manual venting will be required for fresh air and dehumidification.- Optimum insulation values on all six planes (includes under the floor). Exterior insualtion has its benefits in that it cuts off the bridging between inside and outside (in every season). Insulation that manages moisture and air flow to cut other costs and to catch the infiltration/exfiltration and stack-effect mistakes you don't know about (ie cellulose, not fiberglass)- Window placement and glazing square footage selected and placed to lean towards heating or cooling, depending upon your local micro climate.- Active heating - radiant properties such as hot water rads or in-floor tubes. If fire wood is available at reasonable cost, small and distributed wood stoves. Not forced air - increases positive pressure and therefore exfiltration. - PV or wind energy; or DIY hydro if you have the appropriate watersourse available.To save post-construction operating costs, go with insultation and air sealing, controlled venting, best placement and best roof lines. This means sitting on piers or posts and superinsulating the floor along with all other exterior cavities.If your sincerely concerned with "earth friendly technology" you won't use (1) concrete or (2) fiberglass-- their embodied energy costs and environmental (mining and manufacturing phases)impacts are exteem.
*Tedd...I think you can come down now from the podium (cause I want to expound my thoughts as well)...]some major differences in thoughts I have with many actually..point one...I believe you missed some basics...I have trees that grow leaves in the summer naturally blocking summer sun. Trees are way better than huge overhangs...Point two....mass is not a big deal now with superinsulated homes like ones built with SPFs...Point three...Air...mechanical air exchange systems are rediculous...The best part of owning a well insulated home is the freedom to crack the windows for fresh air without concern about the heat bill!Just a few of my opposing thoughts...near the stream,ajPoint four...And the idea of building on piers is really whacked as to me....Build on full basement...over foam...and use the space for living space and let the concrete be the thermal mass...(I like the two birds or more with one stone idea but wish the birds lived some how...Anyone know an analogy where the birds live?)
*excellent solar book:The Passive Solar House - Using solar design to heat and cool your home - by James Kachadorian, 1997, A Real Goods Independent Living Bookhey jack ... my points exactly ... except for the basement. If one has the bucks, use isolated concrete slab but remember ITS NOT GREEN. Anyone who says they are environment conscious and then uses concrete (ie the embodied energy issue) is suckin' and blowin' at the same time. I think the truth is, we want independence, as long as it doesn't mess up our back yard. Since the energy and pollution from FG and crete are indirect, few realize what they are supporting in terms of energy and environmental impacts when they use them. I think "passive solar" is overplayed. I agree that superinsulation and passive interior environment control are the issues and the solutions.By the way, decidious trees with no leaves, in front of a south facing window effectively blocks solar gain in the heating seasons. I keep my trees on the weather side of the house and leave the east-south-west arc clear for the windows to absorb the sun.
*At my home the sun tracks below the tree limbs...And you are definitely right that independence is first and foremost on the list...I will go off grid someday unless the monthly fee is dropped...Same for cable and telephone...the monthly fee for the privilage is not for me...near my own stream...ajenviroment is important....but way more complex than one man's thoughts on concrete.
*I agree... its independence for me, too. That's why superinsulating and independent energy solutions are my way as well. I don't want to mortgage it either, so the cost has to be kept down to the dollar a day I can afford to save to buy the next plank.As far as embodied energy goes, its not this man who came up with it. Lots and lots of literature and web sites are talking about "green" buildings and embodied energy impacts. The Green House project in Canada has references. Most of the energy responsible sites speak of the amount of energy taken to produce concrete and FG. Styrofoam is another example.
*Ya Tedd...I totally understand this embodied idea...but it is flawed by the real laws of nature...Quantum mechanics...The mere act of observance will alter outcomes...Just try when the whole World says the stock market is done for, it upticks instead...Why? because of the Quantum Nature of Nature...Fractally yours from near the stream of organised chaos,aj
*Has this thread changed to the "zen of homebuilding"?
*I think its the Tao.AJ is tickling my fancy instead of pulling my chain. I just received my new Trace Inverter today and the solar panels and wind generator are on back order. I can't wait to flick that switch after I install this system in the spring. I have been working off a 1500watt generator all summer and soon I will be tapped directly to Quantum Nature, Jack. The hydro company was willing to install power lines 4000' across private property just to get me hooked up (pun intended). With cell phone, solar and wind power, and propane, I can operate a fully functional home without that grid connection. Next year I plan to to get a Thermomax roof top solar hot water heater. It will boil water on a winter's day in February. That will be solar-pumped into my radiant heating and DHW system and reduce my propane demand by 80% -- leaving me with a gas fridge and stove. Even a cloths washer can be run off the solar/wind system.Yahoo ... and I don't mean search engine. Although much of my research was done on yahoo. Even the research on embodied energy. I got no concrete, no styrofoam, and no fiberglass ... and I am a free man without a guilty environmental-conscience.You guys might find it interesting that the World Bank has established a policy to support/finance the privatization of the worlds fressh water resources. Several trans-national corporations have estblished thmselves as World Bank partners and are systematically purchasing/acquiring the rights to fresh water around the world. The World Bank predicts that the next (impending?) war will inge on water control, not oil. Odd to take a privatization postion if they believe this prediction. Coincidentally, the main issue (that's consistently kept out of the press) in the Israel/Palestine situation is control over water rights.
*Lake George is filled with millions of gallons of drinking water...No war gonna happen here over it ever...Its clean anough to drink as you swim....near the stream and a beaut of a Lake,aj
*Wish I could say the same for the thousands of sq miles of lakes and rivers in my neighbourhood.
*Gentlemen, thank you all for your responses. But please don't let my interjection halt the debate if any of you have more to say.Todd- Your off the grid goals are admirable. I have dreamed the same thing myself. And I would do it, except for my loving wife. She won't hear of it. She likes the convenience of plugging into that duplex outlet and bumping the stat when she's cold. But Part of the goal of this place (that I didn't really mention because it's a little extreme) is that if we lose power for a week in the winter, we can stay warm, and eat, and basically hunker down and wait it out. WHile I would certainly love to incorporate the technology to tell Baltimore Gas & Electric to kiss my a$$, I don't think the finance director would approve . . . . You see, I'm a closet homesteader and want to incorporate as much as I can to make this place as self sufficient as possible. But at the same time, I can't sacrifice too many modern ways that the wife is comfortable with before she will scream foul!! If you want to discuss off line how you have incorporated some of this stuff, I'm listening.Thanks again to everyone.
*Chris: Thanks for the feedback. Too often we just spout off with no feedback on whether is did any good, or even if it was on target.As for being "off the grid"; when you figure the cost per kw, unless you get someone to give you the gear it is almost always cheaper to buy the kw than generate it yourself. On the other hand if there is some reason to have backup power a good generator properly switched and wired, And Tested Regularly, is cheap peace of mind. I've lived off the grid a couple times in my life and know people who do it now. They do it because they have to, not because they want to.My comment on "earth friendly": Most of the so called Green utility production is anything but when the entire manufacturing, distribution, installation, operation and disposal process is considered. Mostly, what it does is displace the effect to some other location, which indirectly comes back to impact us. So, don't automatically think that solar heat or electricity is "earth friendly". A good example I ran into a few years ago was wind generated electricity. It sounded good. But the units required a lot of maintenance, driving up the cost and driving down reliability. They found it killed a lot of birds because for some reason, that I now forget, birds couldn't see the wind blades. So, yeah no fuel was burned but the cost in parts and death to the animals we share the planet with was very high.
*Chris ...Sounds like you and your wife don't undersand off-grid technology and what it is capable of doing today. There is not a single domestic appliance that doesn't work in the independent energy system I am using. I can plug anything in and the controls run it all automatically. This was my criteria as well since my wife and our many family visitors don't want to (and I don't want them to) have to play around with esoteric house components. They only way you would know that I am off the grid is that you won't find a meter counting up those KwHrs nor a monthly bill to pay for electricity. tedd
*Gentlemen. Re the need for added mass. From my 1989 letter to Ned Nisson, then editor of Energy Design Update."One of the things that helped turn me into an anti? passive solar, i.e. anti Mazria, Balcomb, et al, was their refusal to consider, let alone accept, the evidence presented to one of their conferences in San Diego in 1976.One of the surprising? findings of research into the effects of adding thermal mass to so-called superinsulated structures was that it had little effect on heating performance. A house with 30,000 pounds of mass had that mass increased by 50% to 45,000 lbs. Although there was a difference in the thermal performance of the house with and without the mass, it was a difference that made no difference.[Those of you who had philosophy will remember William James's dictum "A difference that makes no difference is no difference.] The cost of the added 15,000 lbs. was such that the payback period was some 500 years. Increasingly the evidence challenges some of the long theorized beliefs of those obsessed with mass. These continuing studies are welcome because they substantiate what the findings of early research into the effects of mass on heavily insulated houses. All the more surprising since since I assume the Finnish houses were not heavily insulated? [The May 1989 issue of Energy Design Update reported on a field monitoring study of two Finnish houses that showed that thermal mass has no effect on heating energy consumption during winter and only a slight savings effect during spring.]The unfortunate consequence of all this research is that it seesm to have little effect on many in the passive solar community. The less rigid among these now recognize the need to reassess the place of mass in structures."Compare, for example, the performance of the 1977 Leger House(it was and still is a bright sunny comfortable, livable, energy efficient, low maintenance "home"}with the New Jersey Kelbaugh house. The kelbaugh has an all glass two story south facing wall behind which is a Trombe wall--named after a Frenceman who did not invent it. See the article "An Affordable Solar House" in the 1979 proceedings of the 4th National Passive Solar Conference. The Leger House is not a solar house. GeneL.
*Gene et alWhile I was professing mass with solar, I in fact went with low mass (wood frame and super-insulated floor with no basement). I am still designed for solar gain but not storage. Instead, I am relying on insulation and air-tightness with low temp hot water radiant/convection heating.Interesting, I just read an article downloaded from Plumbing and Mechanical Journal web site by Seigenthaler about the problems of mass-dependent passive solar. His points are against using it with hydronic heating. dan holohan.com (Heating Help.com) recommends using a point set thermostat in the floor to avoid this problem.So I apologize for making mass a necessary feature of the perfect house. Instead I would say that its isolation from the outdoors that is most important. My independent energy solution costs around $5,000. US. That's not much when one saves over $1,200. to $1,500. year at New York electricity rates. Kw's aren't getting any cheaper, either.And by the way, there is no such thing as green building if one uses plywood, OSB, polystyrene, argon glass, poly vapor barriers, ashphalt roofing, concrete; etc, etc.
*tedd. Someday, soon I hope, when we build houses correctly there will be no super insulated houses, double-envelope houses, "green" houses and so on ad infinitum, there will just houses.By the bye. I'm looking to borrow the following two books: Henmry Rutton's(he was a Canadian) 1860 , Ventilation amd Warming of Buildings, and Wynam's 1804 book, Practical Treatise on Ventilation. There is some interesting stuff on double glazeed windows in those books. Please pass on the word. GeneL
*GeneI understand your sentiments. This day may never come though, as we know who has the most to gain from keeping us in the dark. You can search for these books from your local library and borrow they through university lending arrangements from anywhere in continent.
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I've posted once before, but for those of you that didn't see it, I'm striving for well educated DIY status, and I am not a professional by any means. But here's my situation. Several years in the future, I plan to build a new home. I am looking for traditional styling, probably some sort of bungalow/ranch. At this point, I am gathering information and am looking for any sites/book recommendations/personal opinion or expertise etc as it pertains to passive solar construction. I am following this board intently and reading all I can. I am familiar with the DP cellulose debate, stopping air infiltration from the house into the attic, and a lot of the other topics that are hot here at Breaktime. I also intently read any posts that have to do with ICFs, radiant heat, etc. I still have much to learn. My goal is simple. To build an affordable house that makes the most effective use of the resources I put into it. And once said house is built, I would like for it to be as inexpensive to heat and cool as possible. This is why I am considering some sort of passive solar design.
The way I figure it, if I can combine some of the techniques discussed here with a design that takes full advantage of the homesite and solar gain, I win. But I'm not sure where to start. Can I build and side with claps, or will the lack of thermal mass not produce an effective end result? Do I need to consider brick or stone? Little things like these are what I wonder about.
Sorry if others out there have some expertise, but I know that Gene has some good background in this- can you offer any insight?
So, bottom line, I was hoping to start a discussion and that you guys that have more experience than I could offer arguments for or against, point me in the right direction, or offer up book ideas or websites of interest.
Thanks in advance for any assistance.