||The inner frame which holds glass in
operable and fixed window units.
||the operating portion of a hung or
horizontal sliding window. A single assembly of stiles and rails made into a frame
for holding glass. The framework holding the glass in a window unit. It’s composed of
two stiles (sides) and two rails (top and bottom).
||A coiled spring or spiral system integrated
into the jamb liners to allow double hung or single hung sashes to open and close. They
also allow the sashes to remain open in varied positions..
||In double-hung windows, the rope or chain
which attaches the sash to the counter balance.
||A protruding handle screwed to the inside
bottom rail of the lower sash on a double-hung window. Available on all Pella double-hung
||Generally, a cam-action lock applied to the
check rails of a double/single hung window, or sliding window to pull the check rails
tightly together. They are also applied to the open edges of a projecting window to seal
the sash tightly to the frame. Sash locks provide security and weatherability.
||cover in jamb track that reduces sash travel
on hung windows.
||In older double-hung windows, the concealed
cast-iron weights which are used to counterbalance the sash.
||a continuous screw track in an extrusion.
The track is designed to accept a specific diameter sheet metal screw to provide a secure
means of fastening extrusions without the use of reinforcement.
||See Insulating Glass Unit.
||A flat board cut to fit the contour of a bow
or bay window that’s installed between the sills and the flat wall surface. They
provide a seat or shelf space.
||Safety Glazing Certification Council
– administers tempered glass testing and certification program.
||The measure of how well glazing blocks solar
heat gain relative to 1/8″ clear glass under the same conditions. The lower the
shading coefficient, the better the unit blocks solar heat.
||Wood wedges used to secure the window or
door unit in the rough or masonry opening in a square, level and plumb position during and
||Tall, narrow, fixed or operating sash on
either or both sides of a door to light an entryway or vestibule. Narrow fixed units
mulled or joined to door units to give a more open appearance. Tall, narrow, fixed or
operating sash on either or both sides of a door to light an entryway or vestibule.
||A narrow fixed unit joined to one or more
doors, providing a more open appearance.
||The bottom of a door or window frame.
||The main horizontal member forming the
bottom of the frame of a window or door. The horizontal piece that forms the bottom of a
window frame. It is generally slanted down to the outside to shed standing water. The
lower horizontal member of a window frame.
||extrusion that, when applied below the
window, permits the gap below the window to be closed after window installation.
||The row of bricks, cement blocks or stones
laid horizontally at the bottom of a masonry opening.
|simulated divided light
||A method of constructing windows in which
muntins are affixed to the inside and outside of a panel of insulating glass to simulate
the look of true divided light.
||Use of single panes of glass in a window.
Not as energy-efficient as double glazing.
|single strength glass
||(SSB) 3/32″ thickness.
||A double-hung type of window in which the
top sash is fixed or inoperable
||A special window set into a roof to provide
||A type of window with one fixed sash, and
one that slides sideways — good where outside clearance is limited.
||A window with two or more sashes that slide
horizontally past each other within the frame.
||The absorption of heat from the sun — the
amount of solar radiation (measured in BTUs) received by a surface. Glazing with Solar
Gain Low E coatings optimize the collection of the sun’s heat, and should be used when
heat gain is desired.
|solar heat gain coefficient
||The fraction of incident solar radiation
entering a home through the windows — the lower the number, the better the window is at
blocking heat gain. See Solar Shield.
||The shielding or blockage of the sun’s heat.
Willmar’s Solar Shield Low E coatings provide solar shading, blocking heat gain from the
sun. Glazing with Solar Shield coatings should be used when there is potential for
excessive heat gain, or when heat gain is undesirable.
|solar tempered house
||A dwelling that obtains a large part of its
heat from the sun.
||The percentage of total solar energy that
glazing transmits through a window — a standard clear dualpane has a solar transmittance
||The bottom horizontal piece in a frame wall,
usually single or double 2×4’s. The wall is nailed into the deck or rough floor
through the sole plate.
||an extruded shape other than a hollow or a
semi-hollow extruded shape. Less costly to produce compared to semi or hollow shapes.
|Sound Transmission Class
|A rating measure for the ability of glazing
to block out sound from outside sources. The higher the STC rating the better the sound
blockage (and the quieter the home).
||glass mounted between floors of a building.
It is usually made opaque to hide building components.
||A type of window with distinct shapes, such
as octagons, round-tops, ellipticals, rakeheads — virtually any shape can be custom
||A coating deposited on glass or film
atom-by-atom in a precise process inside a vacuum chamber.
||Sound Transmission Class – describes
acoustical control for interior panels, and, even though inadequate, is currently the only
criteria for exterior windows. The higher the number, the better the product is at
resisting typical sound frequencies excluding airplane and train noises.
||a vertical sash member. The vertical side
pieces of a window sash or door panel. The main vertical members of the framework of a
sash or door panel.
||An interior trim piece on a window which
extends the sill and acts as a narrow shelf. The interior horizontal trim piece at the
bottom of the window frame. The shelf-like piece that projects into the room.
||A molding used to hold, position or separate
||refers to extrusions positioned to collect
water leakage through mullions and products and drain it to the exterior. Used where high
performance water resistance is required and for windows joined with mullions. It runs
continuously across the opening width and can be spliced together to cover wide openings.
The ends are sealed with end dams.
||Our day star and the source of life and
energy on earth, located 93 million miles away, with an expected life of 5 billion years.
A tremendous source of “free” energy if harnessed intelligently.
|Glass that has been heat-treated to become
more than three times stronger — also known as safety glass because it breaks into small
pebbles rather than jagged shards. It is used in sliding glass doors and windows
susceptible to impact or breakage.
||Glass manufactured to withstand greater than
normal forces on its surface. When it breaks, it shatters into small pieces to reduce
hazard. Glass that has first been cut to size, then heated to a very high temperature and
then rapidly brought back to room temperature. It will withstand severe punishment from a
blunt object; however, any pointed object will break the glass instantly and the glass
will crumble into many, very small pieces.
||A rectangular projection cut out of a piece
of wood for insertion into a mortise.
||An air space or insulating material which
prevents the direct coupling of a cold surface to a heated surface.
||an element of low conductivity
(polyurethane) placed between elements of higher conductivity (aluminum) to reduce the
flow of heat and cold.
||The addition of a thermal insulating
material between two thermally conductive materials.
||The direct coupling of a cold surface to a
heated surface, allowing heat transfer via conduction.
||the amount of heat storage capacity
available in a given material or assembly. Thermal mass in a home (tile floors, stone
fireplace, etc.) will absorb excess heat generated during the day and store it until
ambient temperature drops.
||Electromagnetic radiation emitted by a warm
body — the sun, cousin Frank, the cat, etc.
||The ability of a material to impede the flow
of heat. See R-value.
||baking the organic paint finish on aluminum
to endure a tight bond and long life.
||Glass other than clear, with a color cast or
tint. Typically tinted glass absorbs and blocks heat, and reduces visible light
||glass of special formulation to produce
light reducing and/or heat absorbing glass products (bronze, gray or green).
||A basis for measurement, evaluation and
performance comparison of different glazing configurations, established by a formula
combining R-values of the frame area, edge of glass area, and center of glass area.
||A glazing such as frosted glass, which
transmits electromagnetic radiation (light) but causes scattering so that a clear image
cannot be seen.
||A window installed above another window or
||A small window that fits over the top of a
door or window, primarily for additional light and aesthetic value.
||Clear glazing which transmits light without
diffusion, and which can be seen through clearly.
||An insulating glass unit consisting of three
panes of glass with two internal air spaces.
|true divided light
||A term which refers to windows in which
multiple individual panes of glass or lights are assembled in the sash using muntins. This
traditional method of window construction does not have the strength or durability of the
Integral Light Technology™ used in Pella Architect Series® windows.
||a measurement of heat transmission. The U
value of a window is measured by the number of BTU’s that will pass through each square
foot of area per degree of temperature difference from one side of the window to the other
(the lower, the better). U value = the number 1 divided by the R value
|ultraviolet radiation (uv)
||Electromagnetic radiation from the sun, with
wavelengths shorter than visible light — UV-caused fading of furnishings, artwork, etc.
after prolonged exposure to direct sunlight can be a problem. Classical measurement of UV
transmittance (300 — 380 nm) is generally used to indicate fading potential and to
compare UV-blocking performance of various glazing types. Krochmann is a damage-weighted
function developed in Europe used by some to compare product performance.
||A casement locking system which secures the
window at two locking points by operation of one handle.
||the sum total of one window width and one
window height expressed in inches.
||Rate of heat flow-value through the complete
heat barrier, from room air to outside air. The lower the U-value, the better the