Q — I saw some unique skylights on a recent new-home tour that really
brightened up the rooms. I want to install a venting model, but I have an attic
above it. Can I still install one and what features are best?-Art W.
A — You are absolutely correct about the enhancing effect of adding
a skylight to an otherwise ordinary room. I installed a large super-efficient
one in my own family room. It brightened up the room so much that, for several
weeks, I inadvertently walked over and tried to switch off the lights when I
left the room.
Although skylights are certainly easier to install
in a room with a sloped cathedral or vaulted ceiling, they are most often installed
in rooms with flat ceilings with an attic above. All you have to do is build
an insulated tapered lightwell between the roof and the ceiling.
From an energy-efficiency standpoint, adding a high-quality
efficient skylight is almost a wash during the winter. To reduce heat losses,
I mounted a magnetic clear plastic storm window under my skylight to form a
dead air space, and it is barely noticeable. Installing a skylight reduces the
need for electric lights and, with the proper orientation, it provides some
passive solar heat gain from the sun. A true solar south (slightly different
from magnetic compass south) is best. A southwestern orientation is next best.
In all but the hottest climates, avoid a northern exposure. Installing a venting
skylight, as you mentioned, can be a real energy saver in the summer. Since
the hottest air in a room stagnates up at the ceiling, the skylight will exhaust
it. This creates a natural airflow, drawing fresh cooler outdoor air in your
With the new controls available, skylights are convenient
to open and close. A hand-held remote control or wall-mounted control is good
for skylights in a lightwell, but you will have to run electric wiring to the
skylight. If you have only a standard hand-crank rod, you probably won’t open
it as often as you should, thereby cutting down on maximum energy savings in
If you have been to a local home center store to
look for skylights, you have probably seen, at most, only 5% of the styles and
designs available. There is a huge array of shapes, frame designs, flat and
domed glass and plastic glazing, etc., and each type has its advantages. Many
of the smaller commercial models also work well for residential use. Two major
design features to consider are the frame and the glazing materials. The strongest
skylights have solid frames made of wood with durable aluminum cladding on the
exterior. These are also attractive with the natural wood exposed indoors.
Another strong design fuses a fiberglass frame to
the clear or tinted glazing for a leak-proof unit. The glazing options are similar
to new efficient window glass. Double-pane glass, with a low-emissivity coating
and argon gas in the gap between the panes, is a good choice for most homes
and climates. Super-efficient Heat Mirror glass is available for cold climates.
For a steeply pitched roof, as is often found in
a remodeled attic, a floor-to-ceiling balcony-style skylight is ideal. It is
made of two large sections. When it is opened, the lower half, which is hinged
at the bottom, forms a balcony with a handrail. The upper half becomes a glass
cover over your head.
Proper sizing of a skylight is also important. If
the skylight is too small, it will not provide adequate natural light or ventilation.
If it is too big, there will be excessive heat loss in the winter and it will
look out of proportion for the room. A good rule of thumb is that the skylight
area should be about 5% of the room floor area.