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Insulating
Shades and Blinds
Most of my articles have
something to do with saving energy,
and this article is no different.
In
this article, I wanted to talk about the single largest area of our
homes that
is wasteful of energy, and it is so large and so apparent that most
people
never even consider it. Our
attic? No.
Our appliances?
No. Our
lights?
No. It
is our windows.
Consider your house as an
envelope. We’ll
call it our thermal envelope. The
parts of it that keep the cold (or excess heat)
out are the floor, the
ceiling, and the walls. In
terms of
simple square footage, your walls make up a much larger area than does
your
floor and ceiling combined. Your
walls
are exposed the most to the frigid northern winds during the winter,
whereas
your ceiling is mostly protected by the roof, and the floor is not
exposed to
the winds. Your
walls can, at this
latitude, take a direct pounding by 100F+ degree heat for 8 or more
hours in
the summer months, especially on the western side of the house, whereas
your
ceiling is once again mostly protected by the roof and the floor is not
exposed
to the sun.
So, let’s focus
on the walls. Walls
are measured with an overall “R”
value. An
“R” value is simply a number
that is assigned to a material’s ability to insulate, or to
resist hot or
cold. The measuring
stick is simply
block of wood. A
piece of wood that is
one inch thick has an “R” value of
“1”.
So… a piece of wood that is one
inch thick has an insulating value of
R-1. This is what
all other insulating
materials are judged against. The
type
of insulation that is most commonly in the attics of the homes in Idaho
is a loose fill
fiberglass. This
type of insulation has
a rough value of R-3 per inch (some types are 2.5, while others are
3.5). So,
let’s say you have 10 inches of loose
fill fiberglass in your attic. You
have
an insulating value of roughly R-30 in the attic.
In times gone past, that was considered
enough. But, the US
Department of Energy
has recently revised their “R” value standards.
These are very interesting, and can be seen on
their web site.
Back to your walls.
Most walls are built with 2x4 studs during
construction. The
area between the studs is typically
filled with fiberglass batts. This
normally gives your walls a rating of about R-11.
Many homes are now being constructed using
2x6 studs… providing an “R” value of
R-19 (or
so). Look
around at your walls. Better
yet, measure them on the outside of
your house. Figure
out how many square
feet of wall space you have. Then,
figure
out how many square feet of windows you have.
You will see that your windows can account for
10%, or even 20% or more
of your actual wall space. So,
your wall
is an R-11 or maybe an R-19… but only that portion of your
wall that is not
made of glass.
So, what about this glass
that makes up a significant
portion of your thermal envelope?
Over
half the homes in this country still have single paned windows. On average, that equates
to about an R-1 in
protective insulating value. Millions
of
homes have the old aluminum framed double panes from the 60’s
and 70’s. By
now, there is likely no airtight thermal
seal remaining between those panes and they, too, are worth barely more
than an
R-1. A good,
modern, double paned vinyl
window typically rates about an R-2 insulating value.
There are a few rare and expensive types that
even get to an R-3 or slightly higher.
So… it is easy to see that, by far,
the weak point in any home’s thermal
envelope is the windows.
So, what to do? How
do we address this issue? Planting
certain types of trees in the right locations can help a bit when it
comes to
strategic shading, but it does nothing to address the insulating value
of the
windows. Replacing
all your windows can
be horribly expensive. Yes,
it will
reduce your energy bills and make a more comfortable house, but what
you save
in energy each month might often take 20 or more years to recoup the
cost of
the new windows. In
other words… how
long does it take to make them pay for themselves.
Only a real good energy audit can determine
this. Window
salesmen will, of course,
tell you the recoup time is much much shorter, and it can indeed be,
but the
norm is 20+ years. Is
there a better
way?
An
important thing to remember regarding insulation:
it is that it is not the fiberglass (or the glass) that is does the actual
insulating…
rather, it is the air that is trapped within the
fiberglass. That is
why modern double paned windows
typically rate an R-2 value, whereas a single pane might make it to an
R-1
value. Air is the
key. Air itself is
a fantastic insulator. A
single inch of still air has an “R” value
approaching R-5. That’s
right. A single
inch of air can be almost 5 times
more effective at insulating than an inch of wood.
The trick is to turn air into any ally in
making your windows more energy efficient.
Take a wool blanket, or a thick towel, and
simply tape it up over the
inside of one of your windows. You
will
immediately notice the difference.
The
air between the blanket and the glass instantly becomes an insulator. Not a practical solution I
agree. But just try
it and you’ll be amazed at the
difference.
There
are numerous shade/blind companies out there that are
finally realizing this and are capitalizing on this phenomena. You can now find shades
that are not only
attractive, but are made of a modern synthetic fiber that has good
insulating
properties. Some
blind companies are
going even further, and they make blinds that fold compactly, but when
extended, they form a pleated pattern that basically creates an air
pocket in
between each individual fold of fabric.
Here is the increase in
“R” value.
Some blind companies have taken this a step
further and have made the
individual pleats in such a fashion that they actually create two
layers of air
pockets in between three layers of pleat material in between the glass
and the
inside of the room. The
“R” value jumps
again (air = insulation). The problem is…
there is a small gap where
the left and right ends of the blinds do not quite touch the window
frame. There is
also the small gap at the bottom
here the bottom of the blind does not quite touch the window sill. In the winter, heat
escapes from your house
through these gaps and greatly reduces the “R”
value of the pleated shade.
About
a year ago a friend of mine told me about a company in
Northern Vermont
that has tackled this
problem. They are
called Symphony
Shades. What they
have done is create
these plastic tracks that you mount on the inside of your window frame. They have a small plastic
ridge that fits
into a notch cut into the ends of the pleats.
You can hardly see these side tracks, and do
not even notice them unless
one is looking closely at the window frame.
These side tracks eliminate that
“R” stealing gap that occurs naturally
with traditional blinds. When
installed,
these side track blinds add an “R” value of 4.6 to
your thermal
envelope!!! So,
your single paned
windows that might have an “R” value of a
“1”, are instantly transformed into
something that has 400% more insulating strength than the glass alone. Or, your double paned
windows (like exist on my home)
suddenly go from
an R-2 to nearly an R-7!
These
side track blinds can be a bit pricey, especially on
the larger windows. Initially,
I started
buying just one at a time in order to minimize the burden of cost. I recommend you purchase
just one… and
install it in your bedroom. Your
room
will be instantly much warmer in the winter months, and
you’ll be able to turn
your thermostat down without reducing your comfort.
In the summer months, you won’t need
the air
conditioning as much. I
am certain that
you’ll be so impressed, you’ll do like I did and
outfit the entire house with
them. These blinds
have reduced my
monthly heating and cooling costs by about $30 per month. The money I save on
utilities will pay for
the cost of these blinds in only a few years.
So, instead of a 20+ year cost recoup
time… I am looking at recouping
the cost in less than 5 years. After
that, they are just money in the bank.
These
blinds are real easy to install, after you figure out
the first one. The
first one takes a few
moments because these side tracks are unique and they take some time to
visualize and get them on properly.
What
about looks? They
look fantastic! The
come in a great variety of colors and
textures. They even
include options for
blackout shades if you want to outfit a movie or media room. Also, they include options
for reflective
shade… great for windows that face the long beating of the
summer sun (radiant heat) on the
west side of the
house.
The
thing that impressed me the most with this company is
their service. All
of the blinds I
ordered from them were exactly what I ordered and they all fit
perfectly. About
seven months after installing one of
the blinds, it developed a problem in the retraction mechanism and
would not
allow the blind to go up or down.
I sent
them an e-mail asking for advice on how to repair the mechanism. They mailed back to me a
UPS label for
company paid shipping… asking me instead to send the blind
back to Vermont,
so I did. Yesterday,
I arrived home from work to find
my blind had been returned to me in full working order.
No questions asked.
No cost.
This is what has impressed me the most.
These people operate their business with old
fashioned American
values. A good
product at a fair
price. American
made… American
backed. With
fantastic service… standing
behind their product.
So
many companies these days have lost sight of what has
made all that is great in America. They offer cheap products
and have
disclaimers for every possible contingency.
Symphony Shades has taken traditional New England
craftsmanship and ingenuity, and combined it with an ethical standard
that is
all too often seen lacking in today’s business world. I am here to tell you that
this is a company
you can trust, and their blinds are worth their weight in gold. See them on the web where
I found them, at: http://symphonyshades.com/
Proudly
Serving the Following Counties:
Ada, Adams, Boise, Canyon, Gem, Payette, Valley, Malheur and Washington
Oxbow Home Inspections • PO Box 2144 Boise, ID 83616 • 208.573.5300
Troy Farmer: Owner/Inspector • E-Mail: info@troyfarmer.com
© 2007- 2009 Oxbow Home
Inspections and Radon Testing, LLC
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