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When autumn arrives
many homeowners are lured into energy saving procedures and products
that, although will somewhat decrease your energy consumption, are a
poor return on investment. For example, an old 2 X 4 wall with
fiberglass insulation does not have a great R-value (12). To
bolster this protection the first thing a siding salesman will tell
you is to wrap the home with 1''-2” foam sheets. Then you can
put siding over top and your home will be toasty warm. This would be
basically correct if you lived in a windowless box. But many of us
like windows and have a dozen or more in our abode. So we should look
first to the windows and doors before spending too much money on
thickening the walls.
Windows: The Ultimate Energy Suck
Windows come a close second only to siding as
first impression people have of your home. They are not only
physically attractive they provide great views, light, fresh air and
solar heat in the winter. However, government studies show that
they can also account for 10% to 25% of your heating bill. And
during the summer months your air conditioner must work harder to
cool hot air generated by a true “greenhouse effect”
caused by your windows.
You can install Energy-Star-rated windows, which
help a great deal. If you live in the Sun Belt, look into new solar
control spectrally selective windows, which can cut the cooling load
by 10% to 15%.
Single-Pane Dilemma
It is hard to believe that almost most half of
U.S. homes have single-pane windows. Here are a couple of guidelines
depending on which area you live:
1) Winter Areas:
Windows should be gas- filled with low emissivity (low-e) coatings
on the glass to reduce heat loss.
2) Warm Areas:
Windows with selective coatings to reduce heat gain should be
installed.
U and R-Values?
These mysterious numbers have a tendency to
confuse homeowners but here is the “kitchen table”
explanation. U-values are how much
heat is allowed to pass through materials. R-values
are the opposite. They are a gauge for how much heat loss the
material resists from passing through it.
A high R-value indicates energy
efficiency - R-25 is better than R-15, for example
A low U-value indicates energy
efficiency - U-0.30 would be better than U-0.40.
New Home Bonus
If you are building a new home consider putting
your money into the most efficient windows regardless of whether you
live in a warm region or area where winters are long. Why? Consider
this: A lot of the added expense for the energy-efficient windows
will come back to when you purchase the heating and air conditioning
system.
If you decide not to replace your windows, the
simpler, less costly measures listed below can improve their
performance.
Low Tech Solutions for Heat Savings
Using double-sided adhesive tape apply clear
plastic film to the inside of your window frames during the cold
winter months. Remember, the plastic must be sealed tightly to the
frame to help reduce infiltration.
Draw curtains and lower shades at night. Open
them when the sun is shining in.
Seal the edges of older windows with a
removable sealant.
Keep windows clean for the sun to get maximum
penetration.
If you have single-paned windows most
second-hand building supply stores will have storm windows that you
can install. These be as cheap as $5-$10 a window and you can clean
and paint them.
Low Tech Tech Solutions for a Cooler Home
Using methods similar to sun glasses there are
films which can be placed over the glass to repel sun and heat.
Windows with these coatings reflect a lot of the sunlight, keeping
your rooms cooler.
Window shades drapes and blinds can fit the
bill to deflect heat away from the house.
Close any window treatments that face the sun
patterns during the day.
Awnings can be installed on south-facing
windows.
Use reflective films on south-facing windows.
All these methods will help your heat and
electrical bill but the best long-term savings is an investment in
new, quality windows. The pay-back can be long but there are two big
considerations:
Instant decrease in heat loss meaning
n\energy savings
Increased value of your home.
When You Shop for New Windows?
Only windows with the ENERGY
STAR.
A U-value of 0.35 or below is recommended.
These windows have at least double-glazing and a low-e coating.
Select windows with air leakage ratings of
0.3 cubic feet per minute or less.
In warm climates, where summertime heat gain
is the main concern, look for windows with double glazing and
spectrally selective coatings that reduce heat gain.
Have the windows installed by a qualified
window contractor.
Check on solar heat gain co-efficiency
(SHGC), especially if you live in a warm climate.
Materials
Aluminum: Not
recommended unless there is a thermal break, an insulating
plastic seal which separates the metal strips so cold cannot be
quickly transferred inside.
Composite window
frames: This are made from consist of composite wood products,
such as particle board and laminated strand lumber. They are strong
and have good insulating qualities but be careful that they are
treated to prevent rot and water damage.
Fiberglass Frames:
These are strong, stable and have great insulating qualities.
However, chweck and see that they are treated to prevent breakdown
from ultraviolet light (UV) rays over time.
Vinyl: This is
becoming the most popular choice for home owners.Vinyl window frames
are usually made of polyvinyl chloride (PVC) with ultraviolet light
(UV) stabilizers to keep sunlight from breaking down the material.
PVC is a very versatile plastic with good insulating value. Vinyl
window frames also do not require painting and have good moisture
resistance. However, at high temperatures, they may expand and warp;
at extremely low temperatures, they may crack. Also, if sunlight hits
the material for many hours a day, colors other than white may tend
to fade over time.
Doors
Exterior doors used to be paneled wood with a
storm door attached to the outside frame for warmth and protection
from the rain, snow or sun. Now the most common doors are
steel-skinned with a core of polyurethane foam. Another choice is
fiberglass. Both choices have to be installed correctly so that the
weatherstripping forms a good seal. Then you don’t a storm
door.
Better than Wood
The R value is R-5 to R-6 (not including the
effects of a window.) For example: A 1-1/2 inch (3.81 cm) thick door
without a window offers more than five times the insulating value of
a solid wood door of the same size.
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