NetNews Usenet Archive 1992 #31/NN_1992_31.iso/spool/sci/energy/6563

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From: Essential Information <[e-mail]>
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Date: 31 Dec 92 12:43 PST
Subject: Re: Energy Ideas - Thermal Env.
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PROVIDE CLOTHING FOR YOUR BUILDING -- INSULATE IT

Proper insulation in a building is important because it prevents
the transfer of heat between a building and the external
environment, as well as between sections within a building.
Attempting to control the temperatures in different zones of a
building will not succeed if heat can travel freely throughout
the building.

All Parts of a Building Should Be Insulated

Walls, ceilings and roofs should all be insulated.  The payback
time for insulation depends upon the amount of insulation
currently in place.  Buildings which have no insulation can
expect a project to pay back in energy savings in a few years.
Wall insulation has the longest payback because of the cost of
repainting.

Floors should be insulated as well.  Slab-on-grade floors should
be insulated around the perimeter with rigid board or foam.  The
board or foam should be placed vertically along the outside edge
of the floor and should extend down at least two feet below the
surface of the floor.
Insulation of structural members, the steel beams which support
the building, is also important.   According to Energy &
Economics, uninsulated structural members can reduce the
performance of roof and wall insulation by up to 20 percent.
Improper insulation also causes water to condense on cool beams,
causing a structure to deteriorate.

A New Development: Gas-Filled Panels

A new type of insulation developed for insulating roofs and walls
is the gas-filled panel (GFP).  GFPs consist of low-emissivity
multilayer baffles enveloped by a sealed barrier and filled with
a low conductivity gas (such as argon or krypton) or air.  These
panels are twice as effective as fiberglass insulation; they
provide R-7.5 per inch thickness, as opposed to R-3 to R-4 per
inch thickness for fiberglass.  In addition, GFPs can replace
CFC-blown foams.  Lawrence Berkeley Laboratories has almost
completed a manufacturing prototype of a GFP building insulator.
Insulation Does Not Cause Poor Air Quality

While insulation definitely improves the thermal performance of a
building, many believe that over-insulating prohibits adequate
ventilation in buildings.  Alarm over indoor air pollutants,
particularly radon, has caused people to believe that leaky
buildings provide more fresh air and improve indoor air quality.


Hunter Lovins of the Rocky Mountain Institute strongly disagrees.
"The answer to indoor air pollution," she stated in an
Architecture article, "including radon, is stopping the poisons~
entry, or, failing that, then ensuring a constant supply of fresh
air prewarmed through heat exchangers.  It is a myth that old
leaky buildings are more healthful than tight superinsulated
buildings.  Research at Lawrence Berkeley Laboratory shows that
you can get much higher concentrations of radon in leaky
buildings than will ever occur in tight buildings with constant,
controlled ventilation.  With heat exchangers, you get
energy-efficient control over the ventilation rates and flow."
("The Performance of Some 1970s Energy Savers," Architecture,
March 1989).  (Contact: Rocky Mountain Institute, 1739 Snowmass
Creek Road, Snowmass, CO  81654, [phone].)

Choosing  a "Green" Insulation

Many insulating materials are made using dangerous chemicals.
Polystyrene, itself a known carcinogen, is usually blown into an
insulating foam with chlorofluorocarbons (CFCs) or
hydrofluorocarbons (HCFCs), both of which deplete atmospheric
ozone and contribute to the growing ozone hole.  Fiberglass must
be handled carefully because splinters of the glass can enter the
lungs.  Cellulose is a safer alternative, but must be treated
with flame retardants.

CASE STUDIES:

Insulating the High School in Yuma, Arizona
The Yuma Union High School District installed R-30 batt
insulation above new suspended ceilings in classrooms at Kofa
High School and R-11 batt insulation in the walls.  Prior to the
installation, the high school had only R-2.5 insulation.  The
building has 360 tons of chiller capacity.  To meet its daytime
cooling demand, the facility manager arranged to make ice at
night to lower the peak electric demand during the day.
Unfortunately, the cooling load had been so large the chillers
had to operate both day and night.  The insulation should allow
the chillers to idle during the day, lowering the peak demand of
the school.  This would entitle the school to a lower electricity
rate with the utility, increasing energy savings.  An additional
benefit is that the chiller plant runs better and will last
longer.  The project cost $55,000 and will eliminate 50 tons of
cooling load in the building.  The energy savings alone, not
including a shift to the lower electric rate, should pay back the
investment in just under three years.  (Contact: Richard
Jernigan, Yuma Union High School District, 472 South 9th Ave.,
Yuma, AZ  85364, [phone].)

National Audubon Society Headquarters
As a part of an energy retrofit at its national headquarters in
New York City, the National Audubon Society insulated its walls
with "Air Krete" insulation.  This insulation, which consists of
air bubbles trapped in a magnesium oxide cement mixture, improved
the R-value of the walls to between R-12 and R-16 (up to three
times the New York Code requirement), depending on the thickness
of the insulation.  This insulation is non-toxic and does not use
CFCs in its manufacture.  (Contact: Kirstin Childes, Croxton
Collaborative Architects, 1122 Madison Avenue, New York City, NY
10028, [phone].)