Pella® Impervia® Casement Windows
|Specifications & Downloads|
|2D Cross Section
- Sizes and Shapes
- Performance Values
- Interior Finishes
- Exterior Finishes
Sizes and Shapes – Pella Impervia Casement Window
- Built-to-order in 1/4" increments.
- Add transoms or adjacent windows for flexible combinations.
- Design data available for egress, vent opening, clear opening, visible glass and frame area.
View all Pella Sizes and Shapes.
Performance Values – Pella Impervia Casement Window
These windows provide outstanding resistance to air and water infiltration, wind and outside noise — while increasing energy efficiency, security and ease of operation.
Optional Foam Insulation
- Insulating foam inside the sash further improves energy efficiency.
NOTE: Optional foam insulation represented by shaded area.
Material – Pella Impervia Casement Window
Pella Impervia windows are made from Pella's patented five-layer, engineered Duracast® fiberglass composite.
- A fiberglass composite sharing the same properties of strength, durability and temperature resistance as materials used in the aerospace industry.
- Allows Pella Impervia products to withstand extreme conditions better than windows made from other materials.
- Highly stable material won't expand, warp or sag in summer heat, or shrink and turn brittle in harsh winter conditions.
|Duracast||Conventional Fiberglass||Aluminum with Thermal Break||Nonreinforced Vinyl|
|Strength||Excellent||Very Good||Very Good||Fair|
|Nine times stronger than vinyl and twice as strong as aluminum.*|
Withstands heat up to 200° F and cold down to -40° F.
Low expansion and contraction rate assures consistent, weathertight seal between sash and frame.
Withstands impacts without deformation.
*In testing performed in accordance with ASTM testing standards, Pella's Duracast fiberglass composite has displayed superior performance in strength, ability to withstand extreme heat and cold, and resistance to dents and scratches.
- Unlike aluminum, which is a natural conductor, Duracast fiberglass composite offers excellent insulating properties and exceptional energy efficiency.
- The U-Factor of the Duracast fiberglass composite frame is 2.4 times better than thermally broken aluminum.
- When compared to thermally broken aluminum, Duracast fiberglass composite offers greater resistance to condensation and superior thermal comfort to those seated near windows.
- Unlike vinyl or aluminum, Duracast fiberglass composite offers low expansion and contraction rates that help ensure a consistent bond between sash and glass and a weathertight fit between sash and frame.
- Duracast fiberglass composite withstands extreme heat (up to 200° F) without warping, sagging or softening — even in dark colors.
- Duracast fiberglass composite withstands extreme cold (as low as -40° F), unlike vinyl, which can become brittle in extreme cold.
- Duracast fiberglass composite withstands major impacts without deformation, especially in cold weather.
- Duracast fiberglass composite features a low-maintenance, factory-applied powder-coat finish that resists chalking and fading — even in dark colors.
View all Pella Materials.
Exterior Finishes – Pella Impervia Casement Window
Pella Impervia casement windows feature a low-maintenance, factory-applied powder-coat paint finish.
- Resists chalking and fading — even in dark colors.
- Available in White, Tan or Brown. And Pella's dual-color option provides more style and design flexibility — the products offer a White interior with the choice of a Tan or Brown exterior.
Learn more about all Pella Exterior Finishes
Glazing – Pella Impervia Casement Window
Pella Impervia casement windows are available with a variety of insulating glass options for optimal design, performance and budget flexibility.
Insulating glass options include:
- Advanced Low-E with argon*
- SunDefense™ Low-E with argon*
- NaturalSun Low-E with argon*
Pella's Low-E glass options reduce the transmission of solar heat gain and ultraviolet light while allowing the transmission of visible light.
View thermal performance for this unit.
*Optional high-altitude Low-E insulating glass does not contain argon in most products.
Learn more about all Pella Glass Options.
Grilles – Pella Impervia Casement Window
Pella Impervia casement windows are available with grilles-between-the-glass that match the frame color and include a variety of grille patterns.
Grilles can be removed to get access to other Designer Series window fashions, like blinds, shades or decorative panels, for cleaning or to change the look.
- Between-the-glass grilles may be used in conjunction with between-the-glass blinds, fabric shades or decorative panels*.
- Interior is available in unfinished wood, primed, White or matched to prefinished stains.
- Exterior finish matches aluminum cladding.
- Grilles can be removed to access blinds, shades or decorative panels* and for glass cleaning.
- Grilles are 3/4" wide.
- Special grille patterns are available.
Learn more about Pella Impervia Casement Grille Profiles, Patterns, Spacing and Visible Glass Design Parameters.
Hardware – Pella Impervia Casement Window
These windows are available with a range of hardware options and finishes to meet most design objectives and budgetary requirements.
- Integrated crank with fold-away handle.
- Patented Unison Locking System.
- Stainless-steel operating arms and hinges.
- Optional limited opening and egress hardware.
- Color-matched or optional finishes.
Integrated Crank with Fold-Away Handle
Improves operation and aesthetics and won't interfere with roomside window treatments — standard feature on all Pella casement windows.
- Standard lock hardware is finished in White, Tan or Brown to match the window color.
- Additional color options: Bright Brass, Satin Nickel and Oil-Rubbed Bronze.
SureLock® Unison Lock System
This patented locking system reaches out to lift and pull the sash against the weatherstripping to form a tight seal. A concealed linkage secures both upper and lower locks with a single easy-to-reach handle.
- One lock installed on units 27-1/2" and smaller frame height.
- Two unison operating locks installed on units over 27-1/2" frame height.
Stainless-steel operator linkage, hinge slide and hinge arms resist rust and corrosion and ensure years of dependable performance.
With the easy-wash feature, the sash moves toward the center of the frame, allowing exterior glass to be cleaned from inside, reducing maintenance costs.
Learn more about all Pella Hardware Options.
Screens – Pella Impervia Casement Window1
Full screens with conventional fiberglass screen cloth are optional for Pella Impervia casement windows. InView™ high-transparency screen fabric is available as an option.
Available as an optional upgrade on Pella Impervia windows.
- Allows in 14% more daylight and 8% more airflow than a conventional fiberglass screen.2
- Made from a screen material that's more transparent than conventional fiberglass screens.
1Warning: Use caution when children or pets are around open windows and doors. Screens are not designed to retain children or pets.
Screen cloth airflow is based on calculated screen cloth openness. Screen cloth transmittance was measured using an integrated sphere spectrophotometer. is disclaimer text.
Learn more about all Pella Screen Options.