What follows is a book review by Rusty Maynard. Would you consider doing a review?
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by William Shurcliff.... Brick House Publishing, 34 Essex St, Andover MA 01810
The superinsulated house concept was first advocated by the Small Homes Council at the Univ of Chicago in 1976
(remember the 1974 oil embargo?). The "LoCal" prototype aimed for heat loss in BTU per hour of 20000
vs 32000 for a well insulated HUD house. The LoCal advocated a goal of $130 for winter fuel (3 times as much required
by the HUD and 5 times as much for typical houses).
In addition to extra insulation (R36 walls with 9" insulation and alternating studs), the superinsulation requires extra gaskets, airlock entries, and special methods for sills and headers. The book is a how to on insulation techniques that should inte rest any homeowner... some technique can be retrofitted, in part .... by adding wall thickness.
In the introduction and Chapter 1, Shurcliff explains his definition of super insulated and he limits his studies to superinsulated designs with certain characteristics. His chosen case studies do not devalue solar gain but they do not have large exp anses of south glass either ( south glass area equals about 8% of gross floor area). A super insulated house would qualify for a modest NC tax credit in the NC formula since the windows are biased to the south wall (about 85% of all glass faces south) and the windows are not just double glass (these are triple glass).
The first half of the book covers Super Insulation and Chapter 6-(Performance) summarizes his opinion of the benefits.Here Shurcliff pops a lot of bubbles.. first by describing how scientists often don't concur on what should be measured in a solar or superinsulated house. He goes on to choice sections that consider the "incremental" cost of insulation, the "fringe benefits" of insulation that go beyond energy savings measured in dollars.
Chapter 6 motivates you to read the preceeding descriptions of superinsulated houses and it contains a jabbing quotation titled "Despair from Connecticut"... "The discovery of how very effective superinsulation can be is very depressing. Almost any b uilding irrespective of size and shape can be insulated. Thus the challenge to architects is destroyed" instead of "strengthening the warming bond between sun and man,architects can plod ahead with dull, outmoded designs of yesterday" bolstered with insul ation. It is obvious that Shurcliff believes that all professionals should attend to providing livable and affordable buildings...why else has he authored books on solar energy. But he would not describe successful energy designs such as super insulatio n as "depressing".... since there are many other design goals within the mandate of energy efficiency.
The superinsulated house is not alien to values in 1996, it's just uncommon to see the thorough execution of dull boring insulation technique even though building methods and code requirements are improved over past years.
Moving on to the double envelope house there is an aura of radical design and shapes that are definitely not common. In Chapter 1 Shurcliff describes the definition of the houses that he chose to study.... for double envelopes this meant house s with attached greenhouses or sunspaces (with more structural beef than just a provision of southern windows) and of course the sunny space is joined to a unified airspace which completely surrounds the ceiling, north walls, and floor of the house.
After reviewing four "double E" houses Shurcliff is skeptical of their claimed benefits... the function of a "within the wall" air space (the envelope) is considered to be not significantly better than a single wall having a summed insulation value eq ual to the 2 walls. Shurcliff considers the envelope space to be a detour into expensive hope that convective currents will somehow distribute excess heat from sunny areas by day and balance the night time changes... without any proof that such happens.
The Discussion Chapters (6 and 10) have the bearing of a college professor moving easily from data to anecdotal observations to data... to a little cajoling of wishful thinkers and occasional stamping out false optimism.
The reading is a great reminder of the ups and downs of societal expectations in the realm of solar energy. Shurcliff has not dismissed his pupils in a mere 11 Chapters... in Appendix 3, he offers an intriguing proposal for heating a well insulated hou se titled the Santa Claus method of Supplying Supplemental Heat. Anyone ready to sign up for another class???