A Glass Vestibule

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The glass vestibule shuts out winter winds.
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Plants and vegetable starts thrive in the glass portico.

Imagine a cold, windy midwinter day in a Boston suburb.
Then picture yourself–in that chilly city
and on that very January day–basking in the
sun on your front steps and enjoying the first daffodil of
the season … all as a result of some $100 worth of 2 X
4’s, concrete blocks, and (if you don’t want to raid the
local dump) window sash.

Well, I used to have to pick my way up ice-rimmed brick
steps and–when I threw open the front door–be
ushered directly into the living room by a howling wind. In
those days, everyone knew when I arrived.

I got tired of such chilly receptions, however,
and the solution was obvious: I had to construct an
entranceway. Fortunately, my front door faces south,
and–since I like to grow plants–I decided to build a
glass vestibule with a planting bed … just to see what
would come up, as it were.

My project began with a simple design, and the
execution wasn’t much more complicated than the
plan. I just built a raised bed of concrete block faced
with brick. Then I constructed a framework of redwood 2 X
4’s–spaced to correspond to the size of the available
sash–and secured its uprights in the blocks and its
crosspieces to the eaves. Once the glass was put in, the
winter was shut out.

Added Touches

That’s about all there was to the basic construction job,
but I did add an extra wrinkle that you might want
to consider: I made the whole addition demountable.

The section of “ceiling” above the planting bed swings back
under the eaves, the steps remain covered, and
the rest of the glass sash can be removed from the
framework and stored. That way, each spring and summer, the
majority of the entranceway is open to the pleasant

A few winters back, in order to determine just how well the
thermal mass provided by the raised planting bed in my
sun-powered portico held the heat, I took temperature
readings– before sunrise– through the
month of January. I was pleased to discover that, though I
hadn’t yet sealed the joints to make the area draft proof,
there was a consistent 10 to 20° temperature difference
between the inside of the vestibule and the bone-chilling

(Of course, since I was measuring the addition’s
storage potential, the readings were taken before
the morning sun hit the glass. The temperature difference
on a bright mid-afternoon–when the portico is really
gathering in the solar heat–can be much more

Furthermore, in addition to the obvious, measurable results
of glassing in my entryway, I’ve found that the ground
within the enclosed planting bed never freezes, the
steps stay dry, only gentle breezes (often laden with
the scent of spring flowers) waft into my protected living
room when the door is opened, and my home’s fuel
consumption has, of course, dropped. Moreover, the
greenhouse foyer is an ideal spot for the children to
comfortably strip off their soggy winter outerwear.

Best of all, there’s an extra benefit which warms
my gardener’s heart. Yes, I do have daffodils in
January (miniature Narcissus asturiensis ) and
they’re just as breathtaking as their bigger, later
relatives. And shortly thereafter come the cheerful white
stars of Ipheion uniflorum– along with
crocuses to supply splashes of color–followed by the
spicy scent of wallflowers. I’ve also found that
carnations, camellias, jasmine, aucuba, and hardy cyclamens
can survive in the solar doorway. Even my delicate
eucalyptus–which is now three winters old–is still
going strong!

Around the first of March, the bitter cold of winter ends,
and the gentle sun and cool nights are perfect for starting
many types of seedlings. At that time of year the
glass portico serves as a cold frame, and it has proved to be
an excellent place to give all kinds of vegetables and
flowers an early start.

Worth the Effort

I have lived with this unconventional home addition for
nine years now, which is certainly enough
time to evaluate and improve upon it. (This past fall, with
fuel prices up again, I found it cost-efficient to install
double-paned glass.) One of the structure’s
finest features– to my mind–is the
surprisingly minor maintenance it requires: 15 minutes in
the spring to take the glass out and 15 more in the chilly
fall to put it back up. And that’s all there is to it
(except for the self-imposed and pleasant burden of
selecting the next plant to experiment with).

Our northern winter has its place, and it’s been my
great pleasure to put it there! Spring is a much
sweeter season … particularly in January.

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