Your patio door is the gateway to your home’s outdoor space – it should look beautiful and operate with ease. With several styles, materials, budgets, and ways to operate a patio door, there’s a lot to digest.
From swinging doors, to sliding doors, to doors that fold, your local Infinity partner is an expert on patio doors. They’ll provide a free, no-hassle consultation with all the information you need to choose the right door for your home (and without all the jargon).
Still, a patio door is an investment in your home. More information can’t hurt as you weigh your options, and our glossary of door terms is a great place to begin.
Active Panel - Primary operating door panel.
Bi-Fold Door - The Bi-Fold Door features Ultrex fiberglass door panels that are thoughtfully designed to stack tightly for a wide opening and expanded views.
Condensation - Moisture that forms on a surface. This could be a result of a difference in temperature between the surface and the air, or high humidity in the home.
Daylight Opening (DLO) - The area of the door where light passes through; the width and the height of the visible glass.
Decorative Glass - Glass formed by running molten glass through special rollers. These rollers have a pattern on them, causing the glass to become patterned and obscure to create the perfect combination of style and privacy.
French Door - A French Door is a style of door that has wider stiles and rails for a more traditional look on either sliding or swinging doors.
Handing - A term used to describe the right- or left-hand operation of a door.
Hardware - Door hardware includes locks, crank handles, and hinges on doors used to operate and secure them.
Inactive Panel - Fixed or non-operating portion of the door that holds the glass and is separate from the frame.
Insulating Glass - Two panes of glass separated by a spacer and sealed tight.
Inswing French Door - The Inswing French Door opens inwards for uninterrupted views and timeless style.
Keyed Cylinder Lock - A lock providing an exterior entry and locking convenience.
Laminated Glass - Even more durable than tempered glass, laminated glass is often referred to as impact resistant or safety glass as it tends to remain in place when cracked.
Multi-Point Locking System - Multiple point locking mechanisms installed on Inswing French Door and Casement window.
Operator - A moving sash, panel, or unit.
Panel - Stationary or operating portion of the door that holds the glass and is separate from the frame.
Rails - The horizontal part of a sash, door panel, or screen.
Rough Opening - The opening in the wall where a door unit is to be installed. Openings are larger than the size of the unit to allow room for insulation.
Screens - A close-mesh woven screen material of metal or fiberglass attached to an aluminum or wood surround. Screens inhibit entry of insects, yet allow for light, air and unobstructed views.
Sill - The lower, horizontal piece of an exterior door frame that supports the frame.
Sliding French Door - A Sliding French Door is a French-style patio door available in two, three, or four-panel configurations. Left, right, and/or center panels operate when grouped in three. When grouped in four, two center panels slide out to the side to reveal a wide walk-through center opening.
Sliding Patio Door - The Sliding Patio Door features a narrow profile for a more contemporary style and increased daylight opening. Available in configurations similar to the Sliding French Door.
Spacer - Used to separate the two pieces of glass in an insulating glass panel.
Stationary - A non-operating sash, panel, or unit.
Ultrex® - A pultruded composite material made of resin and glass fibers with an integrated proprietary finish. Ultrex Fiberglass is the superior material used in Infinity products.
Unit - One single door.
Weather-Stripping - A strip of resilient material designed to seal the door in order to reduce air and water infiltration.
Astragal - A vertical moulding attached to a panel of a door against which the other panel closes. Usually head and footbolt devices will be found on the astragal side.
Capillary Tubes - A tube inserted into the insulating glass spacer that allows the inside and outside air pressure to equalize in higher elevations.
Divided Lites - Divided Lites are decorative bars permanently adhered to glass (Simulated-Divided-Lites) or between two panes of glass (Grilles-Between-Glass) to add architectural interest to a door.
Footbolt - Optional locking device that locks to the sill on the Sliding French or Sliding Patio door. Keep door slightly opened and locked for ventilation, or shut door and lock for added security.
Glazing - Glazing is the act of installing glass into a window or door.
Grilles Between the Glass (GBGs) - Grilles-Between-the-Glass are dividers placed between the panes of insulated glass to simulate authentic divided lites. GBGs allow for easier door cleaning with no bars on the exterior or interior surface of the glass.
Head Jamb - The horizontal piece forming the top of the frame on a door.
Headbolt - A locking rod device installed vertically in the stile or astragal of a door or screen which when activated secures the door in a stationary position.
Interior Casing - The casing trim used on the interior perimeter of the door. Generally supplied by others except in the case of round top casing which is factory supplied.
Jamb Extension - A jamb-like member, usually surfaced on four sides, which increases or extends the depth of the exterior or interior door frame.
Low E Glass - Extremely thin coating of special low emissivity (low E) metallic material are applied to glass pane to boost energy efficiency and block out UV rays.
Masonry Opening - A brick, stone, or block opening into which a window or door unit is installed including the outside casing.
Mull/Mulling - Mull: the actual components used to attach two or more door units together to form an assembly.
Mulling: the process of attaching two or more door units together.
Mullion - The vertical member of a door frame between openings in a multiple opening frame.
Muntins - Bars that form the decorative grille pattern on a door.
OX - The letters OX or XO identify the operation of as viewed from the exterior. The letter O stands for stationary while the letter X stands for operating.
Pultrusion - The process Marvin uses to create Ultrex fiberglass by pulling strong cables of glass saturated with specially compounded resins through a machine to create various door profiles.
R-Value - The resistance a material has to heat flow is the R-Value. Higher numbers indicate greater insulating capabilities.
Side Jamb - The left and right vertical pieces forming the frame on the door.
Simulated Divided Lites (SDLs) - Simulated-Divided-Lites are permanently adhered in our factory to the outside surfaces of the glass. SDLs have a spacer bar between the panes of glass to offer the traditional look of divided lites.
Solar Heat Gain (SHGC) - The Solar Heat Gain Coefficient (SHGC) measures how much heat from the sun enters your home. The lower the number, the less heat the window lets in. You’ll want a lower SHGC if you have high cooling costs in the summer; a higher SHGC can help warm a home in a colder climate during the winter.
Stiles - The upright or vertical members of the framework of a sash, door, screen, or other panel assembly.
Tempered Glass - Tempered glass increases glass strength to help prevent breakage.
U-Factor - U-factor measures how well a window keeps heat inside your home. A higher number allows more heat to escape; a lower number allows less heat to escape. If you live in a colder climate, you’ll want to look for a low U-factor.
Visible Transmittance (VT) - Measures the amount of visible light that passes through a window. A high VT maximizes daylight.
XO - The letters OX or XO identify the operation of a door unit as viewed from the exterior. The letter O stands for stationary, while the letter X stands for operating.
We hope the glossary of patio door terms is helpful for you. Be sure to check out our other blog articles, as we compare materials and share information on how to pick the right doors and windows for your home.
Interested in learning more? Connect with a local Infinity from Marvin expert for more information!
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