|A door onto a patio is a convenience, but
it can also dramatically change the look
and feel of a room. With a glass siding door,
the room seems to open up to all of nature,
bringing light as well as the view. Beyond
the expected features of size and appearance,
what should you look at closely when buying
a new or replacement patio door?
- The frame may be made of wood, vinyl, or
fiberglass clad. Nothing can match the appearance
of real wood or the finishing options, but
vinyl and fiberglass frames are permanently
colored and require little or no maintenance.
- The construction of the slide is important
to how quietly, easily, and smoothly the
door moves. Metal glides are standard. The
best doors use ball bearing rollers.
- The insulating value of the glass can make
a big difference in the comfort of the room
if you live in a climate with hot or cold
extremes. The resistance of the glass to
heat flow is measured by R value (or its
reciprocal, U value), from 1 or 2 to about
4 with low emission glass (U values from
1 to .25). Larger R values provide better
energy economy (smaller for U values), but
even the best do not compare favorably with
the typical modern wall insulation (for example,
R-19 in New England states).
Finally, the lock construction makes an important
contribution to your security and peace of
mind. Look for solid mounting, strike plates,
and locking pins as well as a track lock
that will prevent moving the door even if
the handle lock fails.