Based in Louisiana but national in scope, for nearly three decades Seal Craft has been efficiently providing custom aluminum window systems to satisfy architectural requirements. Since 1981, Seal Craft Corporation has completed more than 4,000 window projects for a diverse group of clients. Located in every state of the union, these projects have ranged from simple single-family dwellings to complex high-rise condominiums, to historic replication projects—some requiring more than 12,000 custom windows.

Our continuity in ownership and management affords consistency in our business practices. We are repeatedly told “—how easy it is to do business with Seal Craft.” Many of our systems and/or accessories were designed for specific owner's project applications. We welcome the opportunity to collaborate with owners and/or design professionals. We can provide products that meet today's blend of structural, thermal, acoustical, and aesthetic requirements as demanded by the current market for commercial window systems.

The source of our success is the dedicated people here at Seal Craft. From management through production worker, we bring our resources of energy, talent, and experience together to provide the best commercial window solutions available—at competitive prices and with some of the best lead times.

We invite you to become familiar with our fine products. We stand ready to assist you in being successful with your commercial vinyl replacement windows requirements.

AAMA    American Architectural Manufacturers Association - a window industry organization that establishes voluntary standards, e.g., AAMA 101-97, offers certification to those standards, and designations, e.g., H-C40 for a “H ung” “C ommercial grade” with a design pressure of 40 psf.

Adjustment clip hardware on hung window jambs to align jamb after window installation.

AIF  Acoustic Insulation Factor, a sound transmission measure used in Canada

Air infiltration the amount of air leaking in and out of a building through cracks in walls, windows, and doors (the lower, the better).

Ambient temperature The outdoor temperature. Anodic( anodize )  the process that provides a hard, durable oxide film on the surface of aluminum, by electrolytic action.

Apron Interior flat trim piece which is used under the stool at the bottom of the window.

Argon An inert, colorless, and harmless gas used instead of air in sealed spaces between panes of glass in insulating glass units to increase insulation. Argon is less conductive to heat than air.

ASHRAE   American Society of Heating, Air-conditioning and Refrigeration Engineers.

Astragal   The center member of a double door, ( or casement window ) which is attached to the fixed or inactive door panel.

Awning Window   A type of operable window with a top-hinged sash that swings outward at the bottom.  Also called a project-out window.

Back bedding The process of adhering and sealing.

Balance   as used in fenestration, is a mechanical device, normally spring loaded, used in hung windows to counterbalance the weight of the sash during opening and closing.

Balance shoe a specialized hardware item utilized in hung window jamb that connects the balance with the sash.

Bay window   A composite of three windows, usually made up of a large center unit and two flanking units that return at 30- or 45-degree angles to the wall. A bay projects from the wall of the structure.

Bead  a molding or stop placed around a window frame to hold the glass in place by pressure.

Billet   the cylindrical form of aluminum just prior to the extruding process.

Bite a glazing term referring to the dimension of the glazing leg, which overlaps the edge of the glass

Bow window  A composite of four or more window units in a radial or “bow” formation, offering a  gently curved contour. Bow windows also project outward from the walls of the structure.

Brickmold   A type of external casing, which frames Windows and doors. Exterior casing around wood window to cover jambs and provide means for nailing during installation.

BTU   British Thermal Unit - a basic measurement of heat. One BTU equals the amount of heat needed to raise one pound of water by 1 degree Fahrenheit. ( A match contains approximately one BTU )

Casement  A type of window with a side-hinged sash that opens or swings like a door. 

Casing   Molding of various widths, thickness and shapes, applied to the framework of window and door units. Used on the Interior, casing is a flat or attractive molding, which covers the inside edge of the head & jambs and spans the rough opening between the window unit and the wall.

Caulking  Sealants used to seal fixed and movable construction joints and prevent infiltration.

Center of glass   All glass area of a window except that within 2.5" (10cm) from the edge of the glass, used in measuring and calculating glazing performance such as R-values and U-values.

CFM  cubic feet per minute  ( ft³/min ) - a unit of measure as used in air infiltration testing, i e -  "maximum 0. 10 cfm per square foot”.

Check rail On a double-hung window, the bottom rail of the upper sash and the upper rail of the lower sash, where the lock is mounted. The top rail of the lower sash and the bottom rail of the upper sash, which meet when a double-hung window is closed. Both pieces should be weather stripped for maximum weather-ability. As called a “meeting rail”.

Circlehead  A generic term referring to any of a variety of window units with one or more curved frame members, often used over another window or door opening.

Cladding An aluminum material locked to the outside faces of many Pella products to provide a durable, low-maintenance exterior surface.

Clerestory A window placed vertically in a wall above one "s line of vision to provide natural light -- often at the intersection of two offset roof planes.

CMR Centerline of Meeting Rail - a reference line used to locate integral mullions and/or size oriel (unequal) sash, e.g., "the height of the lower sash shall be 22" from the frame sill to CMR."

Collection The act of trapping solar radiation and converting it to heat.

Comfort Engineering Optimizing glazing selections on a window-by-window basis to fulfill a prioritized set of objectives -- e.g., comfort, energy efficiency (both summer and winter), UV protection, natural lighting, desired aesthetics, views, and budget. Willmar Windows" sales consultants act as expert comfort engineers, finding appropriate solutions for individual needs.

Condensation The change of a gas to a liquid state. Because warm air can hold more water vapor than cold air, as warm air cools its ability to hold water vapor is reduced. Excess moisture condenses on the warm side of glass. e.g., condensation on the outside of a glass of ice-water.

Conduction A process of heat transfer whereby heat moves directly through a material by molecular agitation.The handle of a cast-iron frying pan becomes hot due to conduction.

Conductivity The transfer of heat through a given material -- see U-value which is the measure of conductivity, the inverse of R-value.

Convection A process of heat transfer whereby heat energy is transferred from one location to another -- created by the motion of air resulting from a difference in temperature and the action of gravity.

Cottage Double-Hung A double-hung window in which the upper sash is shorter than the lower sash.

Crack Length total outside perimeter of window sash/vent; used when defining the AAMA air infiltration rate.

CRF Condensation Resistance Factor - an indication of a window"s ability to resist condensation (the higher the better).

Curb Appeal The visual attractiveness of a home as seen from the street -- often the first impression. Realtors see curb appeal as an influential factor in evaluating and selling homes.

Custodial Lock window hardware only operable with a tool or key.

Daylight Transmittance The percentage of visible light that glazing transmits through a window -- a standard clear dualpane has a daylight transmittance of 82%.

Debridge the process of cutting away the metal on the bottom of an aluminum thermal break cavity once the two-part polyurethane has reached full strength, thus creating a thermally broken extrusion.

Desiccant a porous crystalline substance used to absorb moisture and/or sealant solvents from within the sealed air space of an insulating glass unit.

Design Load the project wind load to be determined by the architect and expressed in psf, e.g., "the project design load shall be 38.7 psf, both positive and negative."

Designation Number prescribed by AAMA. One for each window style. It provides a code for architectural selection, e.g., TR-5000 = DH-C45 = Double Hung - Commercial Grade - 45 psf Design Pressure.

Dessicant Crystalline substance used to absorb moisture from air within IGUs.

Dew Point The temperature at which water vapor will condense as warm, moist air is cooled.

Die a perforated steel block through which aluminum or vinyl is extruded.

Direct Gain A direct gain passive solar system utilizes south-facing windows to open a house to the sun. A large window area accepts direct sunlight while thermal mass serves as storage.

Dormer A space which protrudes from the roof of a house, usually including one or more windows.

Double Glazing Use of two panes of glass in a window to increase energy efficiency and provide other performance benefits.

Double Glazing Panel (DGP) A removable interior glass panel which creates an air space between the exterior glazing and itself. It provides improved insulation and condensation control and allows for between-glass shading options such as muntins, blinds and pleated shades.

Double Strength Glass (DSB) 1/8" thickness.

Double-Hung Window A window unit that has two operable sashes which move vertically in the frame. Two vertically sliding sash which by-pass each other in a single frame. Sashes typically fit within vinyl balances and tilt out and remove for safe, easy cleaning.

Drip Cap A molding placed on the top of the head brickmold or casing of a window frame.

Dry Glazing a method of securing glass in a window frame with a dry, preformed, resilient gasket, without the use of a glazing compound.

Dual Durometer A material that has two or more levels of flexibility. An example is the weatherstripping used between the frame and sash of a Pella casement window.

Dual Durometer Bead a vinyl glazing bead with a softer flap against glass and a harder section inserted into sash member.

Dual Glazed two single lites glazed into a split sash with an airspace, not hermetically sealed, between the two single lites.

Dual Window two windows joined together, one in front of the other, to provide superior sound control.

Dualpane Two panes of glass with a single airspace, held together by an edge spacer -- the most economical IGU.

Edge of Glass The glass area within 2 1/2" (10cm) of the edge of a window.

Egress Window a window with specific release hardware and minimum clear opening size to allow occupants to escape through the window in case of a fire.

Electrostatic a painting process by which the aluminum is grounded and the paint carries a positive electric current. This creates a magnetic attraction between the paint and the aluminum allowing for uniform paint coverage on all exposed extrusion surfaces.

Emissivity Emission, or the ability to radiate heat in the form of long-wave radiation.

End Dam used to close the ends of a subsill so the water will not leak out the ends. It makes the subsill a complete water trough allowing it to collect excess water and drain it to the exterior.

EPDM Ethylene Propylene Diene Monomer - a weather resistant synthetic rubber from which many flexible gaskets for windows are made.

ER Rating Energy Rating number developed by CSA (Canadian Standards Association) to compare the thermal performance of windows. Measured in watts per square meter (W/m2).

Escutcheon Plate hardware for handles etc.

Expansion Mullion self mulling window frame jambs that, when slipped together, permit expansion/contraction while preserving strength and watertightness.

Extension Jambs Flat wood parts which are nailed to the interior edges of the window jamb to extend it in width and adapt to a thicker wall. The inside edge of extension jambs should be flush with the finished wall surface. Interior casing is then nailed into it.

Exterior Glazed glass glazed from the exterior of the building.

Extrude the process of shaping aluminum or vinyl by forcing it through a die.

Extrusion A form produced by forcing material through a die. Pella window frames are clad with extruded aluminum.

Fenestration An architectural term referring to the arrangement of windows in a wall. From the Latin word, "fenestra," meaning window.

Fin Seal a form of pile weatherstrip that has a plastic mylar fin centered in the pile. This fin reduces air infiltration and ensures weatherstrip contact throughout the window's life.

Finger-Jointing A means of joining individual pieces of wood together to form longer lengths. The ends of the pieces are machined to form a set of interlocking fingers, which are then coated with adhesive and meshed together under pressure.

Fixed Non-venting or non-operable.

Fixed Unit A stationary window or door that does not open -- also referred to as a fixed sash.

Flange Frame a window frame with the head, jamb, and sill exterior perimeter leg longer than the interior perimeter leg.

Flashing A thin strip of metal or synthetic material that diverts water away from a window or skylight. A metal or plastic strip attached to the outside of the side jambs and head to provide a weather barrier, preventing leakage between the window frame and wall.

Float Glass transparent glass with flat, parallel surfaces formed on the surface of a pool of molten tin.

Foam Spacer Foam material placed in the airspace of the insulating glass windows to enhance the appearance and improve the performance of the window.

Frame The enclosure in which window sash or door panels are mounted. Outside members of a window unit which enclose the sashes. Composed of side jambs, head jamb and sill.

French Hinged Door Hinged door(s) which have wider panel members around the glass.

French Sliding Door A sliding door which has wider panel members around the glass, giving the appearance of a French hinged door.

Gasket a rubber or plastic pliable material used to separate glazed glass and aluminum or vinyl.

Glazing Glass in a window or door; the act or process of fitting glass or panels into the sash or frame of the window.

Glazing Bead a molding or stop around a window frame to hold the glass in place by pressure. A vinyl or wood strip, applied around the perimeter of the glass on the exterior of the window sash, for holding the glass in place.

Glazing Stop The part of the sash or door panel which holds the glass in place.

Greenhouse Effect The property of glass that permits the transmission of short-wave solar radiation, but is opaque to long-wave thermal radiation. The interior of a car heating up in direct sun illustrates the greenhouse effect.

Grille A term referring to windowpane dividers or muntins, usually a type of assembly which may be detached for cleaning.

Grilles-Between-the Glass Aluminum bars in varying thicknesses and profiles sealed between insulating glass panels to simulate muntin bars.

Gusse ta concealed, strong, right-angled shape used to reinforce mitered corners in tubular aluminum extrusions

Head The main horizontal member forming the top of the window or door frame.

Head Board A flat board, cut to fit the contour of a Bow or Bay window, for installing between the head jambs and the flat wall surface to finish off the area which would normally be ceiling.

Head Expander a u-shaped extrusion slipped over the frame head that, when pushed up, closes the gap above the window after window installation.

Header A horizontal framing member placed over the rough opening of a window to prevent the weight of wall or roof from resting on the window frame. A beam across the top of the rough opening for a window or door. Headers rest on jack studs and support the weight of the wall above the window unit. They are often constructed out of doubled 2x6’s, 2x10’s or 2x12’s.

Heat Fusion (welding) method to join PVC frame and/or sash members by heating the cut ends, squeezing them together, and allowing the assembly to cool.

Heat Treating the process where glass or aluminum extrusions are heated and cooled to make these materials harder and stronger.

Hermetically Sealed Unit an insulating glass unit that is sealed against moisture. The unit is made up of two lites of glass, separated by a roll-formed metal spacer tube (at the full perimeter) which contains a moisture and/or solvent absorbing material. The unit is then completely sealed, creating a moisture free air space.

Hollow Extrusion an extrusion having an enclosed cavity within it.

Hopper A window unit in which the top of the sash swings inward.